Glossary for Huawei OSN

Numerics

3DES

See Triple Data Encryption Standard.

3G

See 3rd Generation.

3GPP

3rd Generation Partnership Project

3R

reshaping, retiming, regenerating

3rd Generation (3G)

The third generation of digital wireless technology, as defined by the International Telecommunications Union (ITU). Third generation technology is expected to deliver data transmission speeds between 144 kbit/s and 2 Mbit/s, compared to the 9.6 kbit/s to 19.2 kbit/s offered by second generation technology.

802.11n

A wireless transmission standard released after 802.11a/b/g by Wi-Fi Alliance. As a new member to the 802.11 protocol family, 802.11n supports the 2.4 GHz and 5 GHz frequency bands and provides a higher bandwidth (300 Mbit/s, much higher than the 54 Mbit/s provided by 802.11a/g) for WLAN access users. In addition, 802.11n supports the MIMO technology, which provides two methods of increasing the communication rate: by increasing the bandwidth and by improving the channel usage.

802.1Q in 802.1Q (QinQ)

A VLAN feature that allows the equipment to add a VLAN tag to a tagged frame. The implementation of QinQ is to add a public VLAN tag to a frame with a private VLAN tag to allow the frame with double VLAN tags to be transmitted over the service provider's backbone network based on the public VLAN tag. This provides a layer 2 VPN tunnel for customers and enables transparent transmission of packets over private VLANs.

802.1X

An access control and authentication protocol based on the client/server mode. It can prevent unauthorized users/equipment from accessing the LAN/WLAN through an access port. After a client (STA) is associated with an AP, the 802.1X authentication result determines whether the STA can use the wireless services provided by the AP. If the STA passes the authentication, the STA can access the resources in the WLAN. If the STA fails to pass the authentication, the STA cannot access the resources in the WLAN.

802.1ag MAC ping

A network administration utility similar to ping. 802.1ag MAC ping works by sending test packets and waiting for a reply to test whether the destination device is reachable. 802.1ag MAC ping is initiated by a MEP and destined for a MEP or MIP at the same maintenance level within any MA.

802.1ag MAC trace

A network diagnositic tool similar to traceroute or tracert. 802.1ag MAC trace works by sending test packets and waiting for a reply to test the path between the local device and the destination device and to locate faults. 802.1ag MAC trace is initiated by a MEP and destined for a MEP or MIP at the same maintenance level within any MA.

A

A/D

analog/digit

A3

algorithm A3

AAA

See Authentication, Authorization and Accounting.

AAL

See ATM Adaptation Layer.

AAL1

See ATM Adaptation Layer Type 1.

AAL5

ATM Adaptation Layer Type 5

ABR

See area border router.

ACAP

See adjacent channel alternate polarization.

ACB

access barred signal

ACH

associated channel header

ACK

See acknowledgement.

ACL

See access control list.

ACM

adaptive clock method

ACR

allowed cell rate

ADM

add/drop multiplexer

ADMC

automatically detected and manually cleared

ADSL

asymmetric digital subscriber line

ADSL2+

asymmetric digital subscriber line 2 plus

AES

See Advanced Encryption Standard.

AF

See assured forwarding.

AFI

address family identifier

AG

See access gateway.

AGC

automatic gain control

AH

See Authentication Header.

AID

access identifier

AIS

alarm indication signal

AKA

See Authentication and Key Agreement.

ALC

See automatic level control.

ALG

See application level gateway.

ALS

See automatic laser shutdown.

AM

See adaptive modulation.

AMI

See alternate mark inversion.

AMR

See adaptive multirate.

AMT

advanced manufacturing technique

AN

access node

ANCP

See Access Node Control Protocol.

ANI

See automatic number identification.

ANSI

See American National Standards Institute.

AOE

ATM over Ethernet

AP

access preamble

APE

automatic power equilibrium

APN

See access point name.

APS

automatic protection switching

ARP

See Address Resolution Protocol.

ARQ

See automatic repeat request.

AS

See autonomous system.

ASBR

See autonomous system boundary router.

ASCII

American Standard Code for Information Interchange

ASE

amplified spontaneous emission

ASIC

See application-specific integrated circuit.

ASL

analog subscriber line

ASM

See any-source multicast.

ASN.1

See Abstract Syntax Notation One.

ASP

active server page

ASPF

application specific packet filter

ATD

attribute discovery

ATI

See any time interrogation.

ATM

asynchronous transfer mode

ATM Adaptation Layer (AAL)

An interface between higher-layer protocols and Asynchronous Transfer Mode (ATM). The AAL provides a conversion function to and from ATM for various types of information, including voice, video, and data.

ATM Adaptation Layer Type 1 (AAL1)

A layer defined in the Asynchronous Transfer Mode (ATM) protocol reference model and located between the ATM and user layers. AAL1 is used to segment and encapsulate user data into ATM cells. It can attenuate delay jitters, prevent cell loss, and perform flow control and error control. It is designed for adaptation of ATM to the voice, image, and data services. AAL1 is dedicated to the voice service.

ATPC

See automatic transmit power control.

ATU-R

ADSL transceiver unit, remote terminal end

AU

See administrative unit.

AUG

See administrative unit group.

AUTN

authentication token

AVP

See attribute-value pair.

Abstract Syntax Notation One (ASN.1)

A syntax notation type employed to specify protocols. Many protocols defined by the ITU-T use this syntax format. Other alternatives are standard text or Augmented Backus-Naur Form (ABNF).

Access Node Control Protocol (ANCP)

An IP-based protocol that operates between the access node (AN) and the network access server (NAS), over a DSL access and aggregation network.

Address Resolution Protocol (ARP)

An Internet Protocol used to map IP addresses to MAC addresses. It allows hosts and routers to determine the link layer addresses through ARP requests and ARP responses.

Advanced Encryption Standard (AES)

An encryption algorithm that is originally used by some U.S. government departments to guarantee the security of some secret but unclassified material. Now, AES has become the most influential encryption standard all around the world. The AES algorithm is used to ensure the system security.

American National Standards Institute (ANSI)

An organization that defines U.S standards for the information processing industry. ANSI participates in defining network protocol standards.

Authentication Header (AH)

A protocol that provides connectionless integrity, data origin authentication, and anti-replay protection for IP data.

Authentication and Key Agreement (AKA)

A user authentication method defined in 3GPP. IMS AKA is used to implement inter-authentication between the UE and the IMS to ensure confidentiality and integrity of the IMS.

Authentication, Authorization and Accounting (AAA)

A mechanism for configuring authentication, authorization, and accounting security services. Authentication refers to the verification of user identities and the related network services;

authorization refers to the granting of network services to users according to authentication results; and accounting refers to the tracking of the consumption of network services by users.

access control list (ACL)

A list of entities, together with their access rights, which are authorized to have access to a resource.

access gateway (AG)

A type of gateway that provides a user-network interface (UNI) such as ISDN. An access gateway is located at the edge access layer of the NGN structure, and provides various methods for connecting users to the NGN.

access point name (APN)

The network identifier defined by the general packet radio system (GPRS)/Universal Mobile Telecommunications System (UMTS). On one hand, an APN helps the GPRS/UMTS identify the gateway GPRS support node (GGSN). On the other hand, an APN identifies the external packet data networks (PDNs) (such as an Internet service provider network and enterprise network) connected through this GGSN or certain associated services (such as Internet access and wireless application protocol services).

acknowledgement (ACK)

A response sent by a receiver to indicate successful reception of information. Acknowledgements may be implemented at any level including the physical level (using voltage on one or more wires to coordinate transfer), at the link level (to indicate successful transmission across a single hardware link), or at higher levels.

adaptive modulation (AM)

A technology that is used to automatically adjust the modulation mode according to the channel quality. When the channel quality is favorable, the equipment uses a high-efficiency modulation mode to improve the transmission efficiency and the spectrum utilization of the system. When the channel quality is degraded, the equipment uses the low-efficiency modulation mode to improve the anti-interference capability of the link that carries high-priority services.

adaptive multirate (AMR)

A type of algorithm that is based on the adaptive rate and adopts Algebraic Code Excitation Linear Prediction (ACELP). Generally, it refers to a codec type.

adjacent channel alternate polarization (ACAP)

A channel configuration method, which uses two adjacent channels (a horizontal polarization wave and a vertical polarization wave) to transmit two signals.

administrative unit (AU)

The information structure which provides adaptation between the higher order path layer and the multiplex section layer. It consists of an information payload (the higher order VC) and an AU pointer which indicates the offset of the payload frame start relative to the multiplex section frame start.

administrative unit group (AUG)

One or more administrative units occupying fixed, defined positions in an STM payload. An AUG consists of AU-4s.

agent

A process that resides in all managed devices. It receives request packets from the element management system, performs the Read or Write operation on managed variables based on the packet types, generates response packets, and returns the response packets to the element management system.

alternate mark inversion (AMI)

A synchronous clock encoding technique which uses bipolar pulses to represent logical 1 values.

any time interrogation (ATI)

A service control function of querying the current status and location information of a subscriber at any time.

any-source multicast (ASM)

A multicast service mode. In ASM mode, any sender can become the multicast source to send information to a multicast group address. After joining the multicast group identified by this address, multiple receivers can receive all the information sent to this multicast group.

application level gateway (ALG)

An ALG consists of a security component that augments a firewall or NAT employed in a computer network. It allows customized NAT traversal filters to be plugged into the gateway to support address and port translation for certain application layer "control/data" protocols such as FTP, BitTorrent, SIP, RTSP, file transfer in IM applications etc. In order for these protocols to work through NAT or a firewall, either the application has to know about an address/port number combination that allows incoming packets, or the NAT has to monitor the control traffic and open up port mappings (firewall pinhole) dynamically as required. Legitimate application data can thus be passed through the security checks of the firewall or NAT that would have otherwise restricted the traffic for not meeting its limited filter criteria.

application-specific integrated circuit (ASIC)

A special type of chip that starts out as a nonspecific collection of logic gates. Late in the manufacturing process, a layer is added to connect the gates for a specific function. By changing the pattern of connections, the manufacturer can make the chip suitable for many needs.

area border router (ABR)

A router that can belong to more than two areas of which one area must be a backbone area.

assured forwarding (AF)

One of the four per-hop behaviors (PHB) defined by the Diff-Serv workgroup of IETF. It is suitable for certain key data services that require assured bandwidth and short delay. For traffic within the bandwidth limit, AF assures quality in forwarding. For traffic that exceeds the bandwidth limit, AF degrades the service class and continues to forward the traffic instead of discarding the packets.

attribute-value pair (AVP)

An information element that includes a header and is used to encapsulate protocol-specific data (for example, routing information) as well as authentication, authorization or accounting information. The Diameter protocol consists of a header followed by one or more AVPs.

automatic laser shutdown (ALS)

A technique (procedure) to automatically shutdown the output power of laser transmitters and optical amplifiers to avoid exposure to hazardous levels.

automatic level control (ALC)

A feature that identifies speech signals and adjusts the sound volume to stay within a comfortable range, improving user experience.

automatic number identification (ANI)

An SS7 feature in which a series of digits, either analog or digital, are included in the call, identifying the telephone number of the calling device.

automatic repeat request (ARQ)

An error control method for data transmission in which the receiver detects transmission errors in a message and automatically requests a retransmission from the transmitter.

automatic transmit power control (ATPC)

A method of adjusting the transmit power based on fading of the transmit signal detected at the receiver

autonomous system (AS)

A network set that uses the same routing policy and is managed by the same technology administration department. Each AS has a unique identifier that is an integer ranging from 1 to 65535. The identifier is assigned by IANA. An AS can be divided into areas.

autonomous system boundary router (ASBR)

A router that exchanges routing information with other ASs.

B

B-ISDN

See broadband integrated services digital network.

B-VLAN

backbone virtual local area network

BA

behavior aggregate

BAS

See broadband access server.

BBE

background block error

BBS

See bulletin board system.

BC

boundary clock

BCCH

broadcast control channel

BCD

binary-coded data

BDI

See backward defect indication.

BE

See best effort.

BER

bit error rate

BFD

See Bidirectional Forwarding Detection.

BG

See border gateway.

BGP

Border Gateway Protocol

BIOS

See basic input/output system.

BIP

See bit interleaved parity.

BIP-8

See bit interleaved parity-8.

BIP-X

bit interleaved parity-X

BITS

See building integrated timing supply.

BMC

best master clock

BMS

business management system

BOM

broadcast overhead message

BPDU

See bridge protocol data unit.

BPS

board protection switching

BRA

See basic rate access.

BRAS

See broadband remote access server.

BRI

basic rate interface

BSC

See base station controller.

BSR

See bootstrap router.

BSS

business support system

BTS

base transceiver station

BTV

broadband TV

BWS

backbone wavelength division multiplexing system

Bidirectional Forwarding Detection (BFD)

A fast and independent hello protocol that delivers millisecond-level link failure detection and provides carrier-class availability. After sessions are established between neighboring systems, the systems can periodically send BFD packets to each other. If one system fails to receive a BFD packet within the negotiated period, the system regards that the bidirectional link fails and instructs the upper layer protocol to take actions to recover the faulty link.

backward defect indication (BDI)

A function that the sink node of a LSP, when detecting a defect, uses to inform the upstream end of the LSP of a downstream defect along the return path.

base station controller (BSC)

A logical entity that connects the BTS with the MSC in a GSM/CDMA network. It interworks with the BTS through the Abis interface, the MSC through the A interface. It provides the following functions: radio resource management, base station management, power control, handover control, and traffic measurement. One BSC controls and manages one or more BTSs in an actual network.

basic input/output system (BIOS)

A firmware stored in the computer mainboard. It contains basic input/output control programs, power-on self test (POST) programs, bootstraps, and system setting information. The BIOS provides hardware setting and control functions for the computer.

basic rate access (BRA)

An ISDN interface typically used by smaller sites and customers. This interface consists of a single 16 kbit/s data (or "D") channel plus two bearer (or "B") channels for voice and/or data. Also known as Basic Rate Access, or BRI.

best effort (BE)

A traditional IP packet transport service. In this service, the diagrams are forwarded following the sequence of the time they reach. All diagrams share the bandwidth of the network and routers. The amount of resource that a diagram can use depends of the time it reaches. BE service does not ensure any improvement in delay time, jitter, packet loss ratio, and high reliability.

bit interleaved parity (BIP)

A method of error monitoring. With even parity an X-bit code is generated by equipment at the transmit end over a specified portion of the signal in such a manner that the first bit of the code provides even parity over the first bit of all X-bit sequences in the covered portion of the signal, the second bit provides even parity over the second bit of all X-bit sequences within the specified portion, and so on. Even parity is generated by setting the BIP-X bits so that there is an even number of 1s in each monitored partition of the signal. A monitored partition comprises all bits which are in the same bit position within the X-bit sequences in the covered portion of the signal. The covered portion includes the BIP-X.

bit interleaved parity-8 (BIP-8)

Consists of a parity byte calculated bit-wise across a large number of bytes in a transmission transport frame. Divide a frame is into several blocks with 8 bits (one byte) in a parity unit and then arrange the blocks in matrix. Compute the number of "1" or "0" over each column. Then fill a 1 in the corresponding bit for the result if the number is odd, otherwise fill a 0.

bit/s

See bits per second.

bits per second (bit/s)

A rate at which the individual bits are transmitted through a communication link or circuit. Its unit can be bit/s, kbit/s, and Mbit/s.

bootstrap router (BSR)

The management core of the PIM-SM network. The BSR collects the C-RP information into an RP-set, encapsulates the RP-set into a Bootstrap message, and advertises the Bootstrap

message to each PIM-SM router in the entire network. The PIM-SM router then calculates the RP corresponding to the specified multicast group according to the RP-set.

border gateway (BG)

A gateway that terminates the Gp interface to a PLMN. This function is typically an edge router supporting the Border Gateway Protocol (BGP) and security protocols such as IP Security (IPSec).

bridge protocol data unit (BPDU)

The data messages that are exchanged across the switches within an extended LAN that uses a spanning tree protocol (STP) topology. BPDU packets contain information on ports, addresses, priorities and costs and ensure that the data ends up where it was intended to go. BPDU messages are exchanged across bridges to detect loops in a network topology. The loops are then removed by shutting down selected bridges interfaces and placing redundant switch ports in a backup, or blocked, state.

broadband access server (BAS)

A server providing features such as user access, connection management, address allocation and authentication, authorization and accounting. It also works as a router featuring effective route management, high forwarding performance and abundant services.

broadband integrated services digital network (B-ISDN)

A standard defined by the ITU-T to handle high-bandwidth applications, such as voice. It currently uses the ATM technology to transmit data over SONNET-based circuits at 155 to 622 Mbit/s or higher speed.

broadband remote access server (BRAS)

A new type of access gateway for broadband networks. As a bridge between backbone networks and broadband access networks, BRAS provides methods for fundamental access and manages the broadband access network. It is deployed at the edge of network to provide broadband access services, convergence, and forwarding of multiple services, meeting the demands for transmission capacity and bandwidth utilization of different users. BRAS is a core device for the broadband users' access to a broadband network.

building integrated timing supply (BITS)

In the situation of multiple synchronous nodes or communication devices, one can use a device to set up a clock system on the hinge of telecom network to connect the synchronous network as a whole, and provide satisfactory synchronous base signals to the building integrated device. This device is called BITS.

bulletin board system (BBS)

A computer system equipped with one or more modems or other means of network access that serves as an information and message-passing center for remote users.

C

CA

Certificate Authority

CAC

See connection admission control.

CAR

committed access rate

CAS

See channel associated signaling.

CATV

cable TV

CAU

See client automatic upgrade.

CBC

cipher block chaining

CBQoS

class based quality of service

CBR

See constant bit rate.

CBS

See committed burst size.

CC

See continuity check.

CCC

circuit cross connect

CCCH

See common control channel.

CCDP

See co-channel dual polarization.

CCITT

Consultative Committee of International Telegraph and Telephone

CCM

central control module

CCS

See Call Center Server.

CDE

common desktop environment

CDMA

See Code Division Multiple Access.

CDMA2000

A 3G technology developed by Qualcomm of the US. Technology competitive with WCDMA, upgraded from CDMA1, and developed by the GSM community as a worldwide standard for 3G mobile.

CDR

See call detail record.

CDT

call detail trace

CDVT

cell delay variation tolerance

CE

See customer edge.

CE1

channelized E1

CEAS

See Customer Equipment Archive System.

CES

See circuit emulation service.

CFM

connectivity fault management

CG

center gap

CGI

See cell global identification.

CHAP

See Challenge Handshake Authentication Protocol.

CID

call instance data

CIR

committed information rate

CIST

See Common and Internal Spanning Tree.

CLC

cluster line-card chassis

CLI

command-line interface

CLK

clock card

CLNP

connectionless network protocol

CLP

See cell loss priority.

CMI

coded mark inversion

CN

core network

CN-CS

core network-circuit switched domain

CN-PS

core network-packet switched domain

CO

central office

COBOL

Common Business-Oriented Language

COPS

Common Open Policy Service

CORBA

See Common Object Request Broker Architecture.

COS

chip operating system

CPCS

common part convergence sublayer

CPE

See customer premises equipment.

CPLD

complex programmable logical device

CPU

See central processing unit.

CR

connection request

CR-LSP

constraint-based routed label switched path

CRC

See cyclic redundancy check.

CRF

connection related function

CRL

See certificate revocation list.

CRPC

case-shape Raman pump amplifier unit for C-band

CSES

consecutive severely errored second

CSF

Client Signal Fail

CSG

closed subscriber group

CSMA/CD

See carrier sense multiple access with collision detection.

CSNP

See complete sequence numbers protocol data unit.

CSPF

constraint shortest path first

CST

See common spanning tree.

CSV

comma-separated values

CT

class type

CT1

channelized T1

CTC

common transmit clock

CTD

cell transfer delay

CTP

connection termination point

CV

connectivity verification

CVC

code verification certificate

CW

control word

CWDM

See coarse wavelength division multiplexing.

Call Center Server (CCS)

The core component of the call center platform, managing calls independent of media types.

Challenge Handshake Authentication Protocol (CHAP)

A method to periodically verify the identity of the peer using a 3-way handshake. During the establishment of a link, the authenticator sends a "challenge" message to the peer. The peer responds with a value calculated using a "one-way hash" function. The authenticator checks the response against its own calculation of the expected hash value. If the values match, the authentication is acknowledged. CHAP provides protection against playback attack.

Code Division Multiple Access (CDMA)

A communication scheme that forms different code sequences by using the frequency expansion technology. Subscribers with different addresses can use different code sequences for multi-address connection.

Common Object Request Broker Architecture (CORBA)

A specification developed by the Object Management Group in 1992 in which pieces of programs (objects) communicate with other objects in other programs, even if the two programs are written in different programming languages and are running on different platforms. A program makes its request for objects through an object request broker, or ORB, and thus does not need to know the structure of the program from which the object comes. CORBA is designed to work in object-oriented environments. See also IIOP, object (definition 2), Object Management Group, object-oriented.

Common and Internal Spanning Tree (CIST)

The single spanning tree jointly calculated by STP and RSTP, the logical connectivity using MST bridges and regions, and MSTP. The CIST ensures that all LANs in the bridged local area network are simply and fully connected.

Coordinated Universal Time (UTC)

The world-wide scientific standard of timekeeping. It is based upon carefully maintained atomic clocks and is kept accurate to within microseconds worldwide.

Customer Equipment Archive System (CEAS)

A system recording the information about all the HUAWEI devices on the network. It records the information about shelves and boards, all engineering information (including cooperation payment), and all maintenance and warranty information. The CEAS consists of the offline tool and the online system.

call detail record (CDR)

A database record unit used to create billing records. A CDR contains details such as the called and calling parties, originating switch, terminating switch, call length, and time of day.

carrier sense multiple access with collision detection (CSMA/CD)

Carrier sense multiple access with collision detection (CSMA/CD) is a computer networking access method in which:

A carrier sensing scheme is used.

A transmitting data station that detects another signal while transmitting a frame, stops transmitting that frame, transmits a jam signal, and then waits for a random time interval before trying to send that frame again.

cell global identification (CGI)

A number that uniquely identifies a GSM cell worldwide. A CGI is the concatenation of a Location Area Identification (LAI) and a Cell Identity (CI). The number format is LAI + CI. CI is a 2-byte BCD, which can be customized by carriers.

cell loss priority (CLP)

A field in the ATM cell header that determines the probability of a cell being dropped if the network becomes congested. Cells with CLP = 0 are insured traffic, which is unlikely to be dropped. Cells with CLP = 1 are best-effort traffic, which might be dropped.

central processing unit (CPU)

The computational and control unit of a computer. The CPU is the device that interprets and executes instructions. The CPU has the ability to fetch, decode, and execute instructions and to transfer information to and from other resources over the computer's main data-transfer path, the bus.

certificate revocation list (CRL)

A list of all canceled certificates. A time-stamped list of certificates that have been revoked by the Certification Authority (CA). The CRL is signed by the issuing CA and is made available to entities that need to reply on a certificate for authentication.

channel associated signaling (CAS)

A signaling system in which signaling information is transmitted within a dedicated voice channel. China Signaling System No. 1 is a type of CAS signaling.

circuit emulation service (CES)

A function with which the E1/T1 data can be transmitted through ATM networks. At the transmission end, the interface module packs timeslot data into ATM cells. These ATM cells are sent to the reception end through the ATM network. At the reception end, the interface module re-assigns the data in these ATM cells to E1/T1 timeslots. The CES technology guarantees that the data in E1/T1 timeslots can be recovered to the original sequence at the reception end.

client automatic upgrade (CAU)

A function that enables a user to automatically detect the update of the client version and upgrade the client. This keeps the version of the client is the same as that of the server.

co-channel dual polarization (CCDP)

A channel configuration method, which uses a horizontal polarization wave and a vertical polarization wave to transmit two signals. The Co-Channel Dual Polarization has twice the transmission capacity of the single polarization.

coarse wavelength division multiplexing (CWDM)

A signal transmission technology that multiplexes widely-spaced optical channels into the same fiber. CWDM widely spaces wavelengths at a spacing of several nm. CWDM does not support optical amplifiers and is applied in short-distance chain networking.

committed burst size (CBS)

A parameter used to define the capacity of token bucket C, that is, the maximum burst IP packet size when the information is transferred at the committed information rate. This parameter must be larger than 0. It is recommended that this parameter should be not less than the maximum length of the IP packet that might be forwarded.

common control channel (CCCH)

A point-to-multipoint bidirectional control channel. A CCCH is primarily intended to carry signaling information necessary for access management functions.

common spanning tree (CST)

A single spanning tree that connects all the MST regions in a network. Every MST region is considered as a switch; therefore, the CST can be considered as their spanning tree generated with STP/RSTP.

complete sequence numbers protocol data unit (CSNP)

A unit that contains brief information about the local LSDB and is used to synchronize the LSDBs of neighbors. CSNPs are sent and resolved at different levels.

connection admission control (CAC)

A control process in which the network takes actions in the call set-up phase (or call re-negotiation phase) to determine which connection request is admitted.

constant bit rate (CBR)

A kind of service categories defined by the ATM forum. CBR transfers cells based on the constant bandwidth. It is applicable to service connections that depend on precise clocking to ensure undistorted transmission.

continuity check (CC)

Ethernet CFM can detect the connectivity between MEPs. The detection is achieved after MEPs transmit Continuity Check Messages (CCMs) periodically.

cross polarization interference cancellation (XPIC)

A technology used in the case of the Co-Channel Dual Polarization (CCDP) to eliminate the cross-connect interference between two polarization waves in the CCDP.

customer edge (CE)

A part of BGP/MPLS IP VPN model. It provides interfaces for direct connection to the Service Provider (SP) network. A CE can be a router, switch, or host.

customer premises equipment (CPE)

The equipment located at an end-user's premises. Most CPEs are telephones or other service equipment. A CPE can be a Mobile Station (MS) or a Subscriber Station (SS). An MS is mobile equipment, and an SS is fixed equipment.

cyclic redundancy check (CRC)

A procedure used in checking for errors in data transmission. CRC error checking uses a complex calculation to generate a number based on the data transmitted. The sending device performs the calculation before transmission and includes it in the packet that it sends to the receiving device. The receiving device repeats the same calculation after transmission. If both devices obtain the same result, it is assumed that the transmission was error free. The procedure is known as a redundancy check because each transmission includes not only data but extra (redundant) error-checking values.

D

DAPI

destination access point identifier

DAS

See Data Access Service.

DB

database

DBA

dynamic bandwidth allocation

DBPS

distributed board protect system

DC

direct current

DCC

See data communications channel.

DCCH

dedicated control channel

DCE

data connection equipment

DCM

See dispersion compensation module.

DCN

See data communication network.

DD

database description

DDF

digital distribution frame

DDI

See direct dialing in.

DDN

See digital data network.

DEI

device emulation interrupt

DES

See Data Encryption Standard.

DF

delivery function

DGE

dynamic gain equalizer

DH

See Diffie-Hellman.

DHCP

See Dynamic Host Configuration Protocol.

DIMM

See dual in-line memory module.

DLAG

See distributed link aggregation group.

DM

See delay measurement.

DMM

distributed message manager

DMS

Datacom Integrated Network Management System

DMT

See discrete multi-tone.

DMTI

See desired Min Tx interval.

DMZ

See demilitarized zone.

DNI

dual node interconnection

DNS

See domain name server.

DNS server

A device that can provide domain name resolution for the client on the network

DOD

dial-on-demand

DPD

dead peer detection

DPI

deep packet inspection

DR

See designated router.

DRAM

dynamic random access memory

DRL

device run log

DS

data service

DS-TE

See DiffServ-aware Traffic Engineering.

DSB

See Data Service Bus.

DSCP

See differentiated services code point.

DSE

dispersion slope equalizer

DSL

See digital subscriber line.

DSLAM

See digital subscriber line access multiplexer.

DSP

See digital signal processor.

DSR

data set ready

DST

daylight saving time

DT

decay time

DTE

See data terminal equipment.

DTM

digital trunk module

DTMF

See dual tone multiple frequency.

DU

downstream unsolicited

DVB

digital video broadcasting

DVB-ASI

digital video broadcast-asynchronous serial interface

DVMRP

See Distance Vector Multicast Routing Protocol.

DWDM

See dense wavelength division multiplexing.

Data Access Service (DAS)

A component of the Business Management Point (BMP), for realizing the transparent access of applications to the database. The DAS shields the types, formats, and locations of data storage.

Data Encryption Standard (DES)

A specification for encryption of computer data developed by IBM and adopted by the U.S. government as a standard in 1976. DES uses a 56-bit key.

Data Service Bus (DSB)

A component of the Business Management Point (BMP). The DSB can convert, disassemble, and assemble data, process complex data logics, subscribe to and deliver data, and route data.

DiffServ

See Differentiated Services.

DiffServ-aware Traffic Engineering (DS-TE)

A technology used to optimize and subdivide network transmission resources, classify traffic, and specify the proportion of each flow to the link bandwidth.

Differentiated Services (DiffServ)

An IETF standard that defines a mechanism for controlling and forwarding traffic in a differentiated manner based on CoS settings to handle network congestion.

Diffie-Hellman (DH)

A public algorithm of key. Two communication parties can obtain the keys by exchanging some data instead of transmitting the key across the link.

Distance Vector Multicast Routing Protocol (DVMRP)

An Internet gateway protocol mainly based on the RIP. The protocol implements a typical dense mode IP multicast solution. The DVMRP protocol uses IGMP to exchange routing datagrams with its neighbors.

DoD

downstream on demand

DoS

denial of service

Dynamic Host Configuration Protocol (DHCP)

A client-server networking protocol. A DHCP server provides configuration parameters specific to the DHCP client host requesting, generally, information required by the host to participate on the Internet network. DHCP also provides a mechanism for allocation of IP addresses to hosts.

data communication network (DCN)

A communication network used in a TMN or between TMNs to support the data communication function.

data communications channel (DCC)

The data channel that uses the D1D12 bytes in the overhead of an STM-N signal to transmit information about operation, management, maintenance and provision (OAM&P) between NEs. The DCC channels that are composed of bytes D1D3 are referred to as the 192 kbit/s DCC-R channel. The other DCC channels that are composed of bytes D4D12 are referred to as the 576 kbit/s DCC-M channel.

data terminal equipment (DTE)

A user device composing the UNI. The DTE accesses the data network through the DCE equipment (for example, a modem) and usually uses the clock signals produced by DCE.

delay measurement (DM)

The time elapsed since the start of transmission of the first bit of the frame by a source node until the reception of the last bit of the loopbacked frame by the same source node, when the loopback is performed at the frame's destination node.

demilitarized zone (DMZ)

A buffer area between an insecure system and the secure system and is used to solve the problem that the external network equipped with a firewall cannot access the internal network server. The DMZ is located between the internal network and the external network. In the DMZ, some public server facilities, such as the enterprise Web server and FTP server, can be located. The DMZ effectively protects the internal network.

dense wavelength division multiplexing (DWDM)

The technology that utilizes the characteristics of broad bandwidth and low attenuation of single mode optical fiber, employs multiple wavelengths with specific frequency spacing as carriers, and allows multiple channels to transmit simultaneously in the same fiber.

designated router (DR)

A functional entity in the TCP/IP network. A DR is selected by the OSPF Hello protocol to prevent repeated link status exchanges between routers in an Open Shortest Path First (OSPF) area. All routers in an OSPF area are connected to a DR. When routing data updates in routers, a message about link status is sent to the DR, and the DR sends the message to routers. Therefore, bandwidth resources can be saved.

desired Min Tx interval (DMTI)

The minimum interval that the local system would like to use when transmitting BFD control packets.

differentiated services code point (DSCP)

According to the QoS classification standard of the Differentiated Service (Diff-Serv), the type of services (ToS) field in the IP header consists of six most significant bits and two currently unused bits, which are used to form codes for priority marking. Differentiated services code point (DSCP) is the six most important bits in the ToS. It is the combination of IP precedence and types of service. The DSCP value is used to ensure that routers supporting only IP precedence can be used because the DSCP value is compatible with IP precedence. Each DSCP maps a per-hop behavior (PHB). Therefore, terminal devices can identify traffic using the DSCP value.

digital data network (DDN)

A high-quality data transport tunnel that combines the digital channel (such as fiber channel, digital microwave channel, or satellite channel) and the cross multiplex technology.

digital signal processor (DSP)

A microprocessor designed specifically for digital signal processing, generally in real time.

digital subscriber line (DSL)

A technology for providing digital connections over the copper wire or the local telephone network. DSL performs data communication over the POTS lines without affecting the POTS service.

digital subscriber line access multiplexer (DSLAM)

A network device, usually situated in the main office of a telephone company that receives signals from multiple customer Digital Subscriber Line (DSL) connections and puts the signals on a high-speed backbone line using multiplexing techniques.

direct dialing in (DDI)

A service that allows an intra-office user to be connected through the PSTN long number of this user. The call does not need to be transferred to this user through the automatic switchboard.

discrete multi-tone (DMT)

A modulation mode of the asymmetric digital subscriber line (ADSL), which uses the frequency division multiplex technology to divide the frequency band in use into multiple subchannels to carry data independently. ITU-T defines the maximum number of bits that each subchannel can carry. In each subchannel, data can be modulated and transmitted independently and the ADSL based on the DMT technology has a strong anti-noise capability. The transmission capability of the ADSL based on the DMT technology is related to the following factors: frequency response (line attenuation), line noise, noise margin, transmit power, preset maximum number of bits that each subfrequency band can carry.

dispersion compensation module (DCM)

A module, which contains dispersion compensation fibers to compensate for the dispersion of transmitting fiber.

distributed link aggregation group (DLAG)

A board-level port protection technology used to detect unidirectional fiber cuts and to negotiate with the opposite end. Once a link down failure occurs on a port or a hardware failure occurs on a board, the services can automatically be switched to the slave board, achieving 1+1 protection for the inter-board ports.

domain name server (DNS)

A functional entity in the TCP/IP network. With deployment of the DNS, subscribers can access related servers using corresponding domain names. In the TCP/IP network, a domain name maps an IP address. Domain names are easier to remember but serves in the network communicate with each other using IP addresses. Therefore the DNS is used to convert domain names to corresponding IP addresses.

dual in-line memory module (DIMM)

A circuit board on which RAM memory chips are mounted. A DIMM is a small circuit board that can hold a group of memory chips. A DIMM is capable of transferring 64 bits instead of 32 bits that each SIMM can transfer. Pentium processors require a 64-bit path to memory so SIMMs must be installed two at a time as opposed to one DIMM at a time.

dual tone multiple frequency (DTMF)

In telephone systems, multifrequency signaling in which standard set combinations of two specific voice band frequencies, one from a group of four low frequencies and the other from a group of four higher frequencies, are used.

E

E-Aggr

See Ethernet aggregation.

E-LAN

See Ethernet local area network.

E-Line

See Ethernet line.

E-Tree

See Ethernet-tree.

E-UTRAN

See evolved universal terrestrial radio access network.

E1

An European standard for high-speed data transmission at 2.048 Mbit/s. It provides thirty-two 64 kbit/s channels. A time division multiplexing frame is divided in to 32 timeslots numbered from 0 to 31. Timeslot 0 is reserved for frame synchronization, and timeslot 16 is reserved for signaling transmission. The rest 30 timeslots are use as speech channels. Each timeslot sends or receives an 8-bit data per second. Each frame sends or receives 256-bit data per second. 8000 frames will be sent or received per second. Therefore the line data rate is 2.048 Mbit/s.

EAPE

enhanced automatic power pre-equilibrium

EAPoL

Extensible Authentication Protocol over LAN

EBGP

External Border Gateway Protocol

EBS

See excess burst size.

EC

See error correction.

ECC

See embedded control channel.

ECM

entitlement control message

EDFA

See erbium-doped fiber amplifier.

EEPROM

See electrically erasable programable read-only memory.

EF

See expedited forwarding.

EFI

See external functionality interface.

EFM

Ethernet in the First Mile

EFM OAM

Ethernet in the first mile OAM

EFT

electrical fast transient

EGP

See Exterior Gateway Protocol.

EIA

See Electronic Industries Alliance.

EIGRP

Enhanced Interior Gateway Routing Protocol

EIR

See equipment identity register.

ELAN

emulated local area network

EM

element management

EMC

See electromagnetic compatibility.

EMI

See electromagnetic interference.

EMS

element management system

EMU

See environment monitoring unit.

EN

end node

EOC

embedded operations channel

EOS

enterprise operation system

EP

elementary procedure

EPL

See Ethernet private line.

EPLAN

See Ethernet private LAN service.

EPLD

See erasable programmable logical device.

EPON

See Ethernet passive optical network.

ERPS

Ethernet ring protection switching

ES

edge server

ESC

See electric supervisory channel.

ESCON

See enterprise system connection.

ESN

See equipment serial number.

ESP

See Encapsulating Security Payload.

ESS

See extended service set.

ETSI

See European Telecommunications Standards Institute.

EUI

extended user interface server

EVC

Ethernet virtual connection

EVOA

electrical variable optical attenuator

EVPL

See Ethernet virtual private line.

EVPLAN

See Ethernet virtual private LAN service.

EXP

See experimental bits.

Electronic Industries Alliance (EIA)

An association based in Washington, D.C., with members from various electronics manufacturers. It sets standards for electronic components. RS-232-C, for example, is the EIA standard for connecting serial components.

Encapsulating Security Payload (ESP)

A key protocol in the IP Security (IPsec) architecture. ESP adopts encryption and authentication mechanisms. It is used in transport mode or tunnel mode to authenticate the source of IP packets, and ensure data integrity, anti-replay, and confidentiality. ESP provides data confidentiality and integrity by encrypting the data to be protected and placing the encrypted data in the data part of the IP ESP. Based on security requirements of subscribers, this mechanism can be used to encrypt either a transport-layer segment or an IP data packet. A transport-layer segment includes Transmission Control Protocol (TCP), User Datagram Protocol (UDP), Internet Control Message Protocol (ICMP), and Internet Group Management Protocol (IGMP).

Ethernet aggregation (E-Aggr)

A type of Ethernet service that is based on a multipoint-to-point EVC (Ethernet virtual connection).

Ethernet line (E-Line)

A type of Ethernet service that is based on a point-to-point EVC (Ethernet virtual connection).

Ethernet local area network (E-LAN)

A type of Ethernet service that is based on a multipoint-to-multipoint EVC (Ethernet virtual connection).

Ethernet passive optical network (EPON)

A passive optical network based on Ethernet. It is a new generation broadband access technology that uses a point-to-multipoint structure and passive fiber transmission. It supports upstream/downstream symmetrical rates of 1.25 Gbit/s and a reach distance of up to 20 km. In the downstream direction, the bandwidth is shared based on encrypted broadcast transmission for different users. In the upstream direction, the bandwidth is shared based on TDM. EPON meets the requirements for high bandwidth.

Ethernet private LAN service (EPLAN)

A type of Ethernet service provided by SDH, PDH, ATM, or MPLS networks. This service is carried over a dedicated bridge and point-to-multipoint connections.

Ethernet private line (EPL)

A type of Ethernet service that is provided with dedicated bandwidth and point-to-point connections on an SDH, PDH, ATM, or MPLS server layer network.

Ethernet virtual private LAN service (EVPLAN)

A type of Ethernet service provided by SDH, PDH, ATM, or MPLS networks. This service is carried over a shared bridge and point-to-multipoint connections.

Ethernet virtual private line (EVPL)

A type of Ethernet service provided by SDH, PDH, ATM, or MPLS networks. This service is carried over a shared bridge and point-to-point connections.

Ethernet-tree (E-Tree)

An Ethernet service type that is based on a Point-to-multipoint Ethernet virtual connection.

European Telecommunications Standards Institute (ETSI)

A standards-setting body in Europe. Also the standards body responsible for GSM.

Extensible Markup Language (XML)

A specification developed by the W3C. XML is a pared-down version of SGML, designed especially for Web documents. It allows designers to create their own customized tags, enabling the definition, transmission, validation, and interpretation of data between applications and between organizations.

Exterior Gateway Protocol (EGP)

A protocol for exchanging routing information between two neighboring gateway hosts (each with its own router) in a network of autonomous systems.

eTOM

enhanced Telecom Operations Map

electric supervisory channel (ESC)

A technology that implements communication among all the nodes and transmission of monitoring data in an optical transmission network. The monitoring data of ESC is introduced into DCC service overhead and is transmitted with service signals.

electrically erasable programable read-only memory (EEPROM)

A type of EPROM that can be erased with an electrical signal. It is useful for stable storage for long periods without electricity while still allowing reprograming. EEPROMs contain less memory than RAM, take longer to reprogram, and can be reprogramed only a limited number of times before wearing out.

electromagnetic compatibility (EMC)

A condition which prevails when telecommunications equipment is performing its individually designed function in a common electromagnetic environment without causing or suffering unacceptable degradation due to unintentional electromagnetic interference to or from other equipment in the same environment.

electromagnetic interference (EMI)

Any electromagnetic disturbance that interrupts, obstructs, or otherwise degrades or limits the effective performance of electronics/electrical equipment.

embedded control channel (ECC)

A logical channel that uses a data communications channel (DCC) as its physical layer, to enable transmission of operation, administration, and maintenance (OAM) information between NEs.

enterprise system connection (ESCON)

A path protocol which connects the host with various control units in a storage system. It is a serial bit stream transmission protocol. The transmission rate is 200 Mbit/s.

environment monitoring unit (EMU)

A type of power and environment monitoring unit. EMU is used to monitor the environment variables, such as the power supply and temperature. With external signal input through the relay, fire alarm, smoke alarm, burglary alarm, and others can be monitored as well. With the display on NMS system, the change of environment can be monitored timely and accurately.

equipment identity register (EIR)

A logical entity responsible for storing in the network the International Mobile Equipment Identities (IMEIs), used in the GSM system.

equipment serial number (ESN)

A string of characters that identify a piece of equipment and ensures correct allocation of a license file to the specified equipment. It is also called "equipment fingerprint".

erasable programmable logical device (EPLD)

A logical array device which can be used to implement the required functions by programming the array. In addition, a user can modify and program the array repeatedly until the program meets the requirement.

erbium-doped fiber amplifier (EDFA)

An optical device that amplifies the optical signals. The device uses a short length of optical fiber doped with the rare-earth element Erbium and the energy level jump of Erbium ions activated by pump sources. When the amplifier passes the external light source pump, it amplifies the optical signals in a specific wavelength range.

error correction (EC)

Technique for restoring integrity in data that is corrupted during transmission. It requires additional information to be sent with the original data and allows the data to be reconstructed from this information if the original data is corrupted.

evolved universal terrestrial radio access network (E-UTRAN)

A new radio access architecture defined in 3GPP R8. It features high transmission rate, low latency, and optimized data packets. In the E-UTRAN network, multiple eNodeBs are deployed. Two layered protocol stacks are used in the E-UTRAN network to transmit data to the user equipment (UE), including the user-plane protocol stack and the control-plane protocol stack. The user-plane protocol stack consists of Packet Data Convergence Protocol (PDCP), Radio Link Control (RLC), Medium Access Control (MAC), and physical sub-layers. For details about E-UTRAN, see 3GPP TS 36.101.

excess burst size (EBS)

A parameter related to traffic. In the single rate three color marker (srTCM) mode, the traffic control is achieved by the token buckets C and E. Excess burst size is a parameter used to define the capacity of token bucket E, that is, the maximum burst IP packet size when the information is transferred at the committed information rate. This parameter must be larger than 0. It is recommended that this parameter should be not less than the maximum length of the IP packet that might be forwarded.

expected response (XRES)

In the UMTS authentication process the network sends RAND (Random Number) to the UMTS Subscriber, XRES is the value that the network is looking for to indicate a positive response.

expedited forwarding (EF)

The highest order QoS in the Diff-Serv network. EF PHB is suitable for services that demand low packet loss ratio, short delay, and broad bandwidth. In all the cases, EF traffic can guarantee a transmission rate equal to or faster than the set rate. The DSCP value of EF PHB is "101110".

experimental bits (EXP)

A field in the MPLS packet header, three bits long. This field is always used to identify the CoS of the MPLS packet.

extended service set (ESS)

A set of one or more interconnected basic service sets (BSSs) that appears as a single BSS to the logical link control (LLC) layer at any station (STA) associated with one of those BSSs.

external functionality interface (EFI)

The EFI service specifies the interface between WAE and components or entities with embedded applications that execute outside of the defined WAE capabilities. This is analogous to providing a plug-in module, which extends or enhances the capabilities of browsers or other applications.

F

FAD

fabric adapter

FC

See fiber channel.

FCB

fan control board

FD

See frequency diversity.

FDD

See frequency division duplex.

FDDI

See fiber distributed data interface.

FDI

See forward defect indication.

FDN

See full distinguished name.

FE

See fast Ethernet.

FEC

See forwarding equivalence class.

FF

fixed filter

FFD

fast failure detection

FIB

See forward information base.

FICON

See Fiber Connect.

FIFO

See first in first out.

FMC

fixed-mobile convergence

FOADM

fixed optical add/drop multiplexer

FPGA

See field programmable gate array.

FQ

See fair queuing.

FR

See frame relay.

FRR

See fast reroute.

FS

frequency slot

FSM

finite state machine

FT

fault tolerance

FTP

File Transfer Protocol

FTTB

See fiber to the building.

FTTC

See fiber to the curb.

FTTH

See fiber to the home.

FWA

See fixed wireless access.

FXO

foreign exchange office

Fax over IP (FoIP)

A technique for facsimile (fax) transmission over the Internet or other IP-based packet network, rather than over the traditional public switched telephone network (PSTN). FoIP typically involves a fax gateway, which not only serves as a physical gate bet

Fiber Connect (FICON)

A new generation connection protocol which connects the host to various control units. It carries single byte command protocol through the physical path of fiber channel, and provides higher rate and better performance than ESCON.

FoIP

See Fax over IP.

fair queuing (FQ)

A mechanism for queue scheduling in which network resource is allocated equally so that delay and jitter time for all traffic are optimal.

fast Ethernet (FE)

Any network that supports transmission rate of 100 Mbit/s. The Fast Ethernet is 10 times faster than 10BaseT, and inherits frame format, MAC addressing scheme, MTU, and so on. Fast Ethernet is extended based on the IEEE802.3 standard, and it uses the following three types of transmission media: 100BASE-T4 (4 pairs of phone twisted-pair cables), 100BASE-TX (2 pairs of data twisted-pair cables), and 100BASE-FX (2-core optical fibers).

fast reroute (FRR)

A technology which provides a temporary protection of link availability when part of a network fails. The protocol enables the creation of a standby route or path for an active route or path. When the active route is unavailable, the traffic on the active route can be switched to the standby route. When the active route is recovered, the traffic can be switched back to the active route. FRR is categorized into IP FRR, VPN FRR, and TE FRR.

fiber channel (FC)

A high-speed transport technology used to build storage area networks (SANs). Fiber channel can be on the networks carrying ATM and IP traffic. It is primarily used for transporting SCSI traffic from servers to disk arrays. Fiber channel supports single-mode and multi-mode fiber connections. Fiber channel signaling can run on both twisted pair copper wires and coaxial cables. Fiber channel provides both connection-oriented and connectionless services.

fiber distributed data interface (FDDI)

A standard developed by the American National Standards Institute (ANSI) for high-speed fiber-optic local area networks (LANs). FDDI provides specifications for transmission rates of 100 megabits (100 million bits) per second on networks based on the token ring network.

fiber to the building (FTTB)

A fiber-based networking scenario. There are two types of FTTB scenarios: multi-dwelling unit (MDU) and business buildings. Each scenario includes the following service types: FTTB to the MDU and FTTB to the business buildings.

fiber to the curb (FTTC)

A fiber-based networking scenario. The FTTC scenario provides the following services: asymmetric broadband services (such as digital broadcast service, VOD, file download, and online gaming), symmetric broadband services (such as content broadcast, email, file exchange, distance education, and distance medical care), POTS, ISDN, and xDSL backhaul services.

fiber to the home (FTTH)

A fiber-based networking scenario. The FTTH scenario provides the following services: asymmetric broadband services (digital broadcast service, VoD, file download, and online gaming), symmetric broadband services (content broadcast, email, file exchange, distance education, and distance medical care), POTS, and ISDN services.

field programmable gate array (FPGA)

A type of semi-customized circuit used in the application specific integrated circuit (ASIC) field. It is developed on the basis of the programmable components, such as the PAL, GAL, and EPLD. It not only remedies the defects of customized circuits but also overcomes the

disadvantage of the original programmable components in terms of the limited number of gate arrays.

first in first out (FIFO)

A stack management mechanism. The first saved data is first read and invoked.

fixed wireless access (FWA)

A wireless access application in which the location of the end-user termination and the network access point to be connected to the end-user are fixed.

forward defect indication (FDI)

A packet generated and traced forward to the sink node of the LSP by the node that first detects defects. It includes fields to indicate the nature of the defect and its location. Its primary purpose is to suppress alarms being raised at affected higher level client LSPs and (in turn) their client layers.

forward information base (FIB)

A table that provides information for network hardware (bridges and routers) for them to forward data packets to other networks. The information contained in a routing table differs according to whether it is used by a bridge or a router. A bridge relies on both the source (originating) and destination addresses to determine where and how to forward a packet.

forwarding equivalence class (FEC)

A class-based forwarding technology that classifies the packets with the same forwarding mode. Packets with the same FEC are processed similarly on an MPLS network. The division of FECs is flexible, and can be a combination of the source address, destination address, source port, destination port, protocol type, and VPN.

frame relay (FR)

A packet-switching protocol used for WANs. Frame relay transmits variable-length packets at up to 2 Mbit/s over predetermined, set paths known as PVCs (permanent virtual circuits). It is a variant of X.25 but sacrifices X.25's error detection for the sake of speed.

frequency diversity (FD)

A diversity scheme in which two or more microwave frequencies with a certain frequency interval are used to transmit/receive the same signal and selection is then performed between the two signals to ease the impact of fading.

frequency division duplex (FDD)

An application in which channels are divided by frequency. In an FDD system, the uplink and downlink use different frequencies. Downlink data is sent through bursts. Both uplink and downlink transmission use frames with fixed time length.

full distinguished name (FDN)

Each record in the configuration data table has an FDN field. The FDN field is used to uniquely identify an MO. The FDN field is generated automatically when the system records the NE configuration data. The FDN value identifies the hierarchy of each MO in the configuration model.

G

G.711

Audio codec standard (A-law or U-law) that uses pulse code modulation (PCM). Its data rate is 64 kbit/s.

GAL

generic associated channel header label

GE

See gigabit Ethernet.

GE ADM

A technique that is used to optimize GE service transport over a Metro WDM network. By using this technique, equipment configured with a high-speed backplane can separately transmit, aggregate, or divert GE services over electrical-layer wavelengths or sub-wavelengths. This achieves cross-connections of wavelengths and end-to-end management of sub-wavelengths over a single device. This technique enables GE convergence and cross-connections at the same time and therefore ensures that network resources are used effectively.

GEM

GPON encapsulation mode

GFP

See Generic Framing Procedure.

GGSN

See gateway GPRS support node.

GMPLS

generalized multiprotocol label switching

GMSC

See gateway mobile switching center.

GMT

Greenwich Mean Time

GNE

See gateway network element.

GPON

gigabit-capable passive optical network

GPRS

See general packet radio service.

GPRS tunneling protocol (GTP)

GPRS Tunneling Protocol (GTP), an IP-based protocol, is used for general packet radio service (GPRS) communication in Global System for Mobile Communications (GSM) and Universal Mobile Telecommunications System (UMTS) networks. The GTP includes GTP-C and GTP-U. GTP-C is used to transmit signaling for path management, tunnel management, mobility management, and location management. GTP-C performs controls on tunnels in which subscriber data is transferred. GTP-U is used to encapsulate subscriber data and transport subscriber data in tunnels. For details about GTP, see 3GPP TS 29.060.

GPS

See Global Positioning System.

GR

See graceful restart.

GRE

See Generic Routing Encapsulation.

GSM

See Global System for Mobile Communications.

GTP

See GPRS tunneling protocol.

GTP-C

GPRS Tunneling Protocol-Control plane

GTP-U

GPRS Tunneling Protocol-User plane

GTS

See generic traffic shaping.

GTSM

Generalized TTL Security Mechanism

GUI

graphical user interface

Generic Framing Procedure (GFP)

A framing and encapsulation method which can be applied to any data type. It has been standardized by ITU-T SG15.

Generic Routing Encapsulation (GRE)

A mechanism for encapsulating any network layer protocol over any other network. GRE is used for encapsulating IP datagrams tunneled through the Internet. GRE serves as a Layer 3 tunneling protocol and provides a tunnel for transparently transmitting data packets.

Global Positioning System (GPS)

A global navigation satellite system. It provides reliable positioning, navigation, and timing services to worldwide users.

Global System for Mobile Communications (GSM)

The second-generation mobile networking standard defined by European Telecommunications Standards Institute (ETSI). It is aimed at designing a standard for global mobile phone networks. The standard allows a subscriber to use a phone globally. GSM consists of three main parts: mobile switching subsystem (MSS), base station subsystem (BSS), and mobile station (MS).

gateway GPRS support node (GGSN)

A functional entity that provides packet data services. It is in charge of the routing and encapsulation of the packet data between the General Packet Radio Service (GPRS) or Universal Mobile Telecommunications System (UMTS) network and the external PDN.

gateway mobile switching center (GMSC)

A type of Mobile Switching Center (MSC), which requests the routing information about a called subscriber and performs interconnection and settlement between networks.

gateway network element (GNE)

A network element that is used for communication between the NE application layer and the NM application layer.

general packet radio service (GPRS)

A packet oriented mobile data service defined by 3rd Generation Partnership Project (3GPP) and employed to connect mobile cellular users to the Public Data Network (PDN). Within the GSM network, it shares the network databases and radio access network and employs functions known as the Packet Control Unit (PCU), Serving GPRS Support Node (SGSN), and Gateway GPRS Support Node (GGSN) to provide packet switching data services across the fixed and radio network.

generic traffic shaping (GTS)

A traffic control measure that proactively adjusts the output speed of the traffic. This is to adapt the traffic to network resources that can be provided by the downstream router to avoid packet discarding and congestion.

gigabit Ethernet (GE)

A collection of technologies for transmitting Ethernet frames at a rate of a gigabit per second, as defined by the IEEE 802.3z standard. GE is compatible with 10 Mbit/s and 100 Mbit/s Ethernet. It runs at 1000 Mbit/s. Gigabit Ethernet uses a private medium, and it does not support coaxial cables or other cables. It also supports the channels in the bandwidth mode. If Gigabit Ethernet is, however, deployed to be the private bandwidth system with a bridge (switch) or a router as the center, it gives full play to the performance and the bandwidth. In the network structure, Gigabit Ethernet uses full duplex links that are private, causing the length of the links to be sufficient for backbone applications in a building and campus.

graceful restart (GR)

In IETF, protocols related to Internet Protocol/Multiprotocol Label Switching (IP/MPLS) such as Open Shortest Path First (OSPF), Intermediate System-Intermediate System (IS-IS), Border Gateway Protocol (BGP), Label Distribution Protocol (LDP), and Resource Reservation Protocol (RSVP) are extended to ensure that the forwarding is not interrupted when the system is restarted. This reduces the flapping of the protocols at the control plane when the system performs an active/standby switchover. This series of standards is called graceful restart.

H

H-VPN

See hierarchy VPN.

H.248

A media gateway control protocol used for communications between the media gateway controller (MGC) and the media gateway (MGW) in the detached gateway architecture so that the MGC can control the MGW. In Universal Mobile Telecommunications System (UMTS) networks, the interface between the MGC and the MGW is the Mc interface and the 3GPP defines specific usage of H.248 over the Mc interface.

HA

See high availability.

HBA

host bus adapter

HDB3

See high density bipolar of order 3 code.

HDLC

High-Level Data Link Control

HDSL

high-speed digital subscriber line

HDTV

See high definition television.

HFC

See high-level foundation classes.

HGMP

Huawei Group Management Protocol

HLR

See home location register.

HMAC

See Hashed message authentication code.

HQoS

See hierarchical quality of service.

HSDPA

See High Speed Downlink Packet Access.

HSI

high-speed Internet

HSL

See high-level script language.

HSM

hitless switch mode

HTML

Hypertext Markup Language

HTTP

See Hypertext Transfer Protocol.

HTTPS

See Hypertext Transfer Protocol Secure.

HVPLS

hierarchical virtual private LAN service

HWTACACS

See Huawei Terminal Access Controller Access Control System.

Hashed message authentication code (HMAC)

A specific construction for calculating a message authentication code (MAC) involving a cryptographic hash function in combination with a secret key.

High Speed Downlink Packet Access (HSDPA)

A modulating-demodulating algorithm put forward in 3GPP R5 to meet the requirement for asymmetric uplink and downlink transmission of data services. It enables the maximum downlink data service rate to reach 14.4 Mbit/s without changing the WCDMA network topology.

Huawei Terminal Access Controller Access Control System (HWTACACS)

A security protocol with enhanced functions on the base of TACACS (RFC1492). Similar to the RADIUS protocol, HWTACACS implements multiple subscriber AAA functions through communications with the HWTACACS server in the client/server mode.

Hypertext Transfer Protocol (HTTP)

An application-layer protocol used for communications between web servers and browsers or other programs. HTTP adopts the request-response mode. A client sends a request to the server. The request consists of two parts: request header and MIME-like message. The request header contains request method, uniform resource locator (URL), and protocol version. The MIME-like message contains request modifiers, client information, and possible body content. Upon receiving the request, the server responds with a status line. The status line includes the message's protocol version, a success or error code, and a MIME-like message, which contains server information, entity meta-information, and possible entity-body content. For details about HTTP, see RFC2616.

Hypertext Transfer Protocol Secure (HTTPS)

An HTTP protocol that runs on top of transport layer security (TLS) and Secure Sockets Layer (SSL). It is used to establish a reliable channel for encrypted communication and secure identification of a network web server. For details, see RFC2818.

hierarchical quality of service (HQoS)

A type of QoS that controls the traffic of users and performs the scheduling according to the priority of user services. HQoS has an advanced traffic statistics function, and the administrator can monitor the usage of bandwidth of each service. Hence, the bandwidth can be allocated reasonably through traffic analysis.

hierarchy VPN (H-VPN)

An L3VPN networking type. Using the hierarchy technology, H-VPN distributes PE functions such as user access and router management to multiple PEs to enhance network scalability.

high availability (HA)

A scheme in which two modules operate in active/standby mode to achieve high availability. When the active module fails, the standby module automatically takes over the system functions of the active module.

high definition television (HDTV)

A type of TV that is capable of displaying at least 720 progressive or 1080 interlaced active scan lines. It must be capable of displaying a 16:9 image using at least 540 progressive or 810 interlaced active scan lines.

high density bipolar of order 3 code (HDB3)

A code used for baseband transmissions between telecommunications devices. The HDB3 code has the following feature: high capability of clock extraction, no direct current component, error-checking capability, and a maximum of three consecutive zeros.

high-level foundation classes (HFC)

A group of encapsulated function databases provided by the iSStar. You can use the provided functions to accelerate script editing.

high-level script language (HSL)

A script language. Based on python, the HSL syntax is simple, clear, and extendable.

home location register (HLR)

A function entity shared by the circuit switching (CS) domain and the packet switching (PS) domain. It is responsible for mobile subscriber data management and location information management. HLR, a network entity of the core network (CN) in the Global System for Mobile Communications (GSM), general packet radio service (GPRS), or Enhanced Data rates for GSM Evolution (EDGE) network, is the central database for the entire network.

I

I/O

input/output

IA

Intel Architecture

IAB

See Internet Architecture Board.

IANA

See Internet Assigned Numbers Authority.

IBGP

Internal Border Gateway Protocol

ICC

See ITU carrier code.

ICMP

See Internet Control Message Protocol.

ICMPv6

See Internet Control Message Protocol version 6.

ICP

IMA Control Protocol

ID

See identity.

IDL

interface definition language

IDN

See integrated digital network.

IDU

See indoor unit.

IEEE

See Institute of Electrical and Electronics Engineers.

IETF

See Internet Engineering Task Force.

IF

See intermediate frequency.

IGMP

See Internet Group Management Protocol.

IGP

See Interior Gateway Protocol.

IGRP

Interior Gateway Routing Protocol

IIOP

Internet Inter-ORB Protocol

IIS

See Internet Information Services.

IK

See integrity key.

IKE

See Internet Key Exchange.

ILM

incoming label map

ILS

instrument landing system

IMA

See inverse multiplexing over ATM.

IMEI

See international mobile equipment identity.

IMS

information management system

IMSI

See international mobile subscriber identity.

IN

intelligent network

IP

Internet Protocol

IP Security (IPSec)

A protocol family defined by the Internet Engineering Task Force (IETF). By authenticating and encrypting each IP packet of a data stream, this protocol family provides high quality, interoperable, and cryptology-based security for IP packets.

IPA

See intelligent power adjustment.

IPM

IP processing module

IPSec

See IP Security.

IPTV

See Internet Protocol television.

IPX

Internet Packet Exchange

IPoA

IP over ATM

IPoE

IP Over Ethernet

IPoEoA

IP over Ethernet over ATM

IPv4

See Internet Protocol version 4.

IPv6

See Internet Protocol version 6.

IS-IS

See Intermediate System to Intermediate System.

ISAKMP

See Internet Security Association and Key Management Protocol.

ISDN

integrated services digital network

ISDN Q.921-User Adaptation Layer (IUA)

A layer that provides transport of signaling messages between the signaling gateway (SG) and the media gateway controller (MGC), including transporting Q.921/Q.931 boundary primitives, communication between layer management modules, and management of active associations.

ISO

International Organization for Standardization

ISP

See Internet service provider.

ISSU

See in-service software upgrade.

IST

internal spanning tree

ISU

integrated system control unit

ITC

independent transmit clock

ITU

See International Telecommunication Union.

ITU carrier code (ICC)

A code assigned to a network operator/service provider, maintained by the ITU-T Telecommunication Standardization Bureau (TSB).

ITU-T

See International Telecommunication Union-Telecommunication Standardization Sector.

IUA

See ISDN Q.921-User Adaptation Layer.

InARP

Inverse Address Resolution Protocol

Institute of Electrical and Electronics Engineers (IEEE)

A society of engineering and electronics professionals based in the United States but boasting membership from numerous other countries. The IEEE focuses on electrical, electronics, computer engineering, and science-related matters.

Integration Script Star (iSStar)

The enhanced platform of the Huawei M2000, which is developed twice. You can complete specific services through the provided HSL and HFC library program on the platform.

Interior Gateway Protocol (IGP)

A routing protocol that is used within an autonomous system. The IGP runs in small-sized and medium-sized networks. The commonly used IGPs are the routing information protocol (RIP), the interior gateway routing protocol (IGRP), the enhanced IGRP (EIGRP), and the open shortest path first (OSPF).

Intermediate System to Intermediate System (IS-IS)

A protocol used by network devices (routers) to determine the best way to forward datagram or packets through a packet-based network.

International Telecommunication Union (ITU)

A United Nations agency, one of the most important and influential recommendation bodies, responsible for recommending standards for telecommunication (ITU-T) and radio networks (ITU-R).

International Telecommunication Union-Telecommunication Standardization Sector (ITU-T)

An international body that develops worldwide standards for telecommunications technologies. These standards are grouped together in series which are prefixed with a letter indicating the general subject and a number specifying the particular standard. For example, X.25 comes from the "X" series which deals with data networks and open system communications and number "25" deals with packet switched networks.

Internet Architecture Board (IAB)

A small group of people who set policies and directions for TCP/IP and the Internet. It is an elected body that listens to formal appeals and writes network architecture documents.

Internet Assigned Numbers Authority (IANA)

A department operated by the IAB. IANA delegates authority for IP address-space allocation and domain-name assignment to the NIC and other organizations. IANA also maintains a database of assigned protocol identifiers used in the TCP/IP suite, including autonomous system numbers.

Internet Control Message Protocol (ICMP)

A network-layer (ISO/OSI level 3) Internet protocol that provides error correction and other information relevant to IP packet processing. For example, it can let the IP software on one machine inform another machine about an unreachable destination. See also communications protocol, IP, ISO/OSI reference model, packet (definition 1).

Internet Control Message Protocol version 6 (ICMPv6)

A basic protocol of IPv6 and generates error messages and informational messages used by IPv6 nodes to report errors and information generated during packet processing.

Internet Engineering Task Force (IETF)

A worldwide organization of individuals interested in networking and the Internet. Managed by the Internet Engineering Steering Group (IESG), the IETF is charged with studying technical problems facing the Internet and proposing solutions to the Internet Architecture Board (IAB). The work of the IETF is carried out by various working groups that concentrate on specific topics such as routing and security. The IETF is the publisher of the specifications that led to the TCP/IP protocol standard.

Internet Group Management Protocol (IGMP)

One of the TCP/IP protocols for managing the membership of Internet Protocol multicast groups. It is used by IP hosts and adjacent multicast routers to establish and maintain multicast group memberships.

Internet Information Services (IIS)

Microsoft's brand of a Web server software, utilizing the Hypertext Transfer Protocol (HTTP) to deliver World Wide Web documents. It incorporates various functions for security, allows for CGI programs, and also provides Gopher and FTP services.

Internet Key Exchange (IKE)

A hybrid protocol that implements Oakley key exchange and SKEME key exchange in the ISAKMP frame. Both Oakley and SKEME define a key exchange method, including the structure of the valid payload, valid payload of transmitted information, handling procedure of the key, and method to use the key.

Internet Protocol television (IPTV)

A system in which video is transmitted in IP packets. Also called "TV over IP", IPTV uses streaming video techniques to deliver scheduled TV programs or video-on-demand (VOD). Unlike transmitting over the air or through cable to a TV set, IPTV uses the transport protocol of the Internet for delivery and requires either a computer and software media player or an IPTV set-top box to decode the images in real time.

Internet Protocol version 4 (IPv4)

The current version of the Internet Protocol (IP). IPv4 utilizes a 32bit address which is assigned to hosts. An address belongs to one of five classes (A, B, C, D, or E) and is written as 4 octets separated by periods and may range from 0.0.0.0 through to 255.255.255.255. Each IPv4 address consists of a network number, an optional subnetwork number, and a host number. The network and subnetwork numbers together are used for routing, and the host number is used to address an individual host within the network or subnetwork.

Internet Protocol version 6 (IPv6)

An update version of IPv4, which is designed by the Internet Engineering Task Force (IETF) and is also called IP Next Generation (IPng). It is a new version of the Internet Protocol. The difference between IPv6 and IPv4 is that an IPv4 address has 32 bits while an IPv6 address has 128 bits.

Internet Security Association and Key Management Protocol (ISAKMP)

A protocol that allows the message receiver to obtain a public key and use digital certificates to authenticate the sender's identity.

Internet service provider (ISP)

An organization that offers users access to the Internet and re