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2008 Cisco Systems, Inc. All rights reserved. Cisco Public

Cisco NetworkersColombia 2008 1

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2008 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 2

Enterprise IP Telephony Design andDeployment TECUCT-1001 Marcelo Nbrega, AlbertoAguayo, Pablo Marrone, Arnaldo Montaner

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Agenda

Introduction

Network Infrastructure

Unified Communications Infrastructure

Unified Communications Applications

Security and Management

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Applications

Scope of This Seminar

1. Understanding what can be built today

2. Learning how to build it

3. To find out more about Unified Communicationsdesign:

http://www.cisco.com/go/srnd/

Router/GW Router/GW

Applications

IP WAN

PSTN

Unified CMUnified CM

Note : Unified CM = Cisco Unified Communications Manager

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The Big Picture: End-to-EndUnified Communications

PBX

TieLines

LargeBranchOffice

SmallBranch

Offices

LegacySite

RoadWarrior

Telecommuter

SRST Unified CMExpress

Rest of the World

IP WAN PSTNInternet

V3PN

The Big Picture: End-to-End Unified

Communications for the Mid-Market

Headquarters

Unified CMApplications

Gatekeeper

GKGK

Unified

CM-BE

Mid-SizeCentral

Office

100500 Users

Unified CM

Mobility

Cisco Unity Connection

SRST

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MediaResources

UC

ProcessingAgents

Gateway/Survivable

Remote

PSTN/IPGatewayUCEndpoints

CommsEndpoints

PSTN

WANAggregation

Router

BranchRouter

Distribution/Core Switch

Campus

Branch

IP WAN

AccessSwitch

AccessSwitch

The Elements of

Unified Communications

Conf

Voice Mail/Unified

Messaging

Web /Audio/Video

Conferencing

XMLPhone

Services

LDAPDirectory

GKGKMTPMTP

XcodeXcode

ConfConf

SiSiSiSiSiSi

SiSiSiSiSiSi

UCApplications

UC Infrastructure


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MediaResources

UC

ProcessingAgents

Gateway/Survivable

Remote

PSTN/IPGatewayUCEndpoints

CommsEndpoints

PSTN

WANAggregation

Router

BranchRouter


Campus

Branch

IP WAN

AccessSwitch

AccessSwitch

The Elements of


Conf

Voice Mail/Unified

Messaging

Web /Audio/Video

Conferencing

XMLPhone

Services

LDAPDirectory

GKGKMTPMTP

XcodeXcode

ConfConf

SiSiSiSiSiSi

SiSiSiSiSiSi

UCApplications

UC Infrastructure


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Agenda

Introduction





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Network Infrastructure Agenda

1. Building a Campus Networkfor Unified Communications

2. Enabling QoS in the Campus

3. Enabling QoS in the WAN

4. Overlaying Wireless LANs

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Campus UC Networks: The Basics StillApply Hierarchical Network Design

1. Access/Distribution/Core hierarchyeach layerhas specific role

2. Modular scalable topologybuilding blocks

3. Easy to grow, understand, and troubleshoot

4. Creates small fault domainscleardemarcations and isolation

5. Promotes load balancing and redundancy

6. Promotes deterministic traffic patterns

7. Incorporates balance of both Layer 2 and Layer3 technology, leveraging the strength of both

8. Utilizes Layer 3 Routing for load balancing, fastconvergence, scalability, and control

9. Sub-second convergence possible

Building Block

Access

Distribution

Core

Distribution

Access

Without a Rock Solid Foundation the Rest Doesnt Matter

SiSi SiSi

SiSi SiSi

SiSi SiSi

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Campus UC Networks:The Access Layer

1. The Access Layer provides aggregation for Voice, Video and Data endpoints

2. Can provide switched or routed accessis typically feature rich

VLANS Do Not Span Access Switches

QoS Trust BoundariesAutoQoSQueuingNetwork Access Control

Automatic Phone DiscoveryPower over EthernetVoice VLAN AllocationMultiple Security Features

Key Features for Unified Communications

Access

Distribution

UC Feature Rich EnvironmentNot Just About Connectivity

To Core

SiSiSiSi

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UC Campus Networks:The Access Layer

1. Separate Voice and Data VLANs create partitioned broadcast domainsin separate IP subnets

2. Cisco Discovery Protocol (CDP) used during Phone boot up to configureVoice VLAN ID

3. Phone also supplied with QoS configuration information

4. For Securitydifferent network policies can be applied for differentsubnets; e.g. WORM attacks can be contained to the Data VLANs

Data VLAN ID = 10Voice VLAN ID = 110

Native VLANNoConfiguration Changes

Needed on PC

802.1Q Encapsulationwith 802.1p Layer 2

CoS

Voice and Data VLANs

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Campus UC NetworksCDP and Inline Power Discovery

1. Cisco Discovery Protocolallows the switch to discoverthe attached inline powered device and negotiate the

power requirements to optimize power consumption in theswitch

13

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Campus UC Networks:The Distribution Layer

1. Important considerations for Unified Communications in the Distribution Layer:Sub-Second Convergence, High Availability, Load Balancing, and QoS

2. The Distribution Layer uses Layer 3 switching and aggregates wiring closet links (accesslayer) and uplinks to the core with route summarization

3. Protects the core from high density peering and problems in the access layer

4. EIGRP/OSPFsub-second convergence possible with timer adjustment, redundant pathload sharing, route summarization,

5. HSRP or GLBP to provide first hop redundancy, sub-second convergence possible withtimer adjustment

Access

Distribution

Fast Convergence, QoS, and High Availability

SiSi SiSi SiSi SiSi

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Campus UC Networks: The Core Layer

1. Backbone for the networkconnects network building blocks

2. Performance and stability vs. complexityless is more in the core

3. Aggregation point for the distribution layer

4. Tune routing protocol timers for sub second convergence

5. Separate core layer helps in scalability during future growth

6. Use hardware accelerated services only to maintain performance

Access

Distribution

Core

Scalability, High Availability, and Fast Convergence

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SiSi SiSi

SiSi SiSi

SiSi SiSi

SiSi SiSi

UC Campus Network Design:Best PracticeBuild Triangles Not Squares

1. Layer 3 redundant equal cost links support fast convergence

2. Hardware basedfast recovery to remaining path

3. Convergence is extremely fast (dual equal-cost paths: no need forOSPF or EIGRP to recalculate a new path)

Triangles: Link/Box Failure Does NotRequire Routing Protocol Convergence

Squares: Link/Box Failure RequiresRouting Protocol Convergence

Model A Model B

Deterministic vs. Non-Deterministic

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UC Campus Network Design:Routing to the Edge?

1. Easier implement, less to get rightNo matching of STP/HSRP/GLBP priority

No L2/L3 Multicast topology inconsistencies

2. Well known tool set

traceroute, show ip route, show ip eigrp neighbor, etc.

3. Most Cisco Catalyst switches supportL3 Switching

4. EIGRP converges in

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Building a Campus UC NetworkSummary

1.Access layer

Automatic PhoneDiscovery

Power over Ethernet

Voice VLAN allocation

Multiple Securityfeatures

QoS Trust Boundaries

AutoQoS

Queuing

Network Access Control

Layer 3 to the edge?

2.Distribution Layer

Fast Convergence

QoS

High Availability

3.Core LayerFast Convergence

Scalability

High AvailabilityWAN Internet PSTN

Server Farm

http://www.cisco.com/en/US/netsol/ns656/networking_solutions_design_guidances_list.html#anchor2

AccessLayer 2

DistributionLayer 3

Core

Layer 3

DistributionLayer 3

AccessLayer 2

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1. Building a Campus Networkfor Unified Communications




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QoS in the CampusTraffic Profiles and Requirements

1. Latency 150 ms

2. Jitter 30 ms

3. Loss 1%

One-Way Requirements

Smooth Benign

Drop sensitive

Delay sensitive

UDP priority

Voice

Bandwidth per CallDepends on Codec,

Sampling-Rate,and Layer 2 Media

Bursty Greedy

Drop sensitive

Delay sensitive

UDP priority

Video-Conf

Latency 150 ms

Jitter 30 ms

Loss 1%

One-Way Requirements

IP/VC Has the SameRequirements as VoIP,

But Has RadicallyDifferent Traffic Patterns

(BW Varies Greatly)

Smooth/bursty Benign/greedy

Drop insensitive

Delay insensitive

TCP retransmits

Data

Data Classes:

Mission-Critical Apps

Transactional/Interactive Apps

Bulk Data Apps

Best Effort Apps (Default)

Traffic Patterns forData Vary Among

Applications

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2008 Cisco Systems, Inc. All rights reserved. Cisco PublicCisco NetworkersColombia 2008 21

SiSi SiSi

SiSiSiSi

Access

Distribution

Core

Why Enable QoS in the Campus?

1. Adding more bandwidth to avoid congestion doesnt really help as thekey issue is buffer size QoS allows drop and delay sensitive traffic tobe sent with priority

Typical 20:1

Data Over-

Subscription

Typical 4:1

Data Over-

Subscription

= Data

= Voice

InstantaneousInterface

Congestion

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Enabling QoS in the CampusCiscos Approach to QoS

Campus Branch Office

Unified CMCluster

SRST

Router

IP WAN

PSTN

Classification: Mark the Packets with a Specific Priority Denoting aRequirement for Class of Service from the Network

Trust Boundary: Define and Enforce a Trust Boundary at the Network Edge

Provisioning: Accurately Calculate the Required Bandwidthfor All Applications Plus Element Overhead

Scheduling: Assign Packets to One of Multiple Queues (Based onClassification) for Expedited Treatment through the Network

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FastEthernet

GigabitEthernet

Ten GigabitEthernet

Campus QoS ConsiderationsWhere Is QoS Required Within the Campus?

No Trust + Policing+ Queuing

Conditional Trust +

Policing + QueuingTrust DSCP + Queuing

Per-User MicroflowPolicing + CoPP

WAN Aggregator

Cisco Catalyst 6500 PFC3

Server Farms IP Phones + PCs IP Phones + PCs

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QoS in the CampusTraffic Queuing and Scheduling in IP Phones

1. Voice media traffic is marked with CoS 5/DSCP EF (high priority)

2. Data traffic from the PC is remarked with CoS 0 (low priority) bythe IP phone switch

P0P1

Priority Q

Data Qs

P2

VoiceCoS = 5CoS = 5

DataCoS = 0

P1 Untrusted:Phone Switch

Rewrites CoS = 0

PC

AccessSwitch

IP Phone Enclosure

Phone

P

P Trusted:

Switch Acceptsincoming CoS

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Campus QoS ConsiderationsEstablishing Trust Boundaries

1 Optimal Trust Boundary: Trusted Endpoint

A device is trusted if it correctly classifies packets

3 Suboptimal Trust BoundaryOnly use if access switch cannot perform classification

2 Optimal Trust Boundary: Untrusted Endpoint

SiSi

Endpoints Access Distribution Core WAN Aggregators

Trust Boundary

1

2

3

SiSiSiSiSiSi SiSiSiSiSiSi

SiSiSiSiSiSi

For scalability, classification should be done as close to the edgeas possible

The outermost trusted devices represent the trust boundary

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QoS in the Campus:

Switch Port AutoQoS1. AutoQoS allows the application of a pre-defined set of QoS

statements to an interface with one CLI command

2008 Cisco Systems, Inc. All rights reserved.TECVVT-100014409_04_2008_c1

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AutoQoS in Access LayerSwitch PortsAutoQoS Example: VoIP Model

1. Voice Traffic identified by QoS (DSCP) value, queued and transmitted

2. Signalling Traffic identified by QoS (DSCP) value, queued and

transmitted

3. All Data Traffic has DSCP value re-marked to 0 then transmitted

4. Bespoke AutoQoS Macros can be configured and applied to ports,e.g. AutoQoS for Voice, Video, Business Data and Best Effort Data

VVLAN +DSCP CS3

Yes

DVLANANY

Remark to DSCP 0 and Transmit DATA

No

VVLAN +DSCP EF

YesTrust and Transmit VOICEStart

No

Trust and Transmit SIGNALLING

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Catalyst (config-if) # auto qos voip cisco-phone

mls qos map cos-dscp 0 8 16 26 32 46 48 56mls qos srr-queue output cos-map queue 1 threshold 3 5mls qos srr-queue output cos-map queue 2 threshold 3 3 6 7mls qos srr-queue output cos-map queue 3 threshold 3 2 4mls qos srr-queue output cos-map queue 4 threshold 2 1mls qos srr-queue output cos-map queue 4 threshold 3 0mls qos srr-queue output dscp-map queue 1 threshold 3 40 41 42 43 44 45 46 47mls qos srr-queue output dscp-map queue 2 threshold 3 24 25 26 27 28 29 30 31

mls qos srr-queue output dscp-map queue 2 threshold 3 48 49 50 51 52 53 54 55mls qos srr-queue output dscp-map queue 2 threshold 3 56 57 58 59 60 61 62 63mls qos srr-queue output dscp-map queue 3 threshold 3 16 17 18 19 20 21 22 23mls qos srr-queue output dscp-map queue 3 threshold 3 32 33 34 35 36 37 38 39mls qos srr-queue output dscp-map queue 4 threshold 1 8mls qos srr-queue output dscp-map queue 4 threshold 2 9 10 11 12 13 14 15mls qos srr-queue output dscp-map queue 4 threshold 3 0 1 2 3 4 5 6 7mls qos queue-set output 1 threshold 1 138 138 92 138mls qos queue-set output 1 threshold 2 138 138 92 400mls qos queue-set output 1 threshold 3 36 77 100 318mls qos queue-set output 1 threshold 4 20 50 67 400

mls qos queue-set output 2 threshold 1 149 149 100 149mls qos queue-set output 2 threshold 2 118 118 100 235mls qos queue-set output 2 threshold 3 41 68 100 272mls qos queue-set output 2 threshold 4 42 72 100 242mls qos queue-set output 1 buffers 10 10 26 54mls qos queue-set output 2 buffers 16 6 17 61mls qos!interface GigabitEthernet0/1srr-queue bandwidth share 10 10 60 20srr-queue bandwidth shape 10 0 0 0queue-set 2mls qos trust device cisco-phonemls qos trust cosauto qos voip cisco-phone

AutoQoS in the CampusAutoQoS Macro Example

1. Enforces a trust boundary at CiscoIP Phones

2. Enforces a trust boundary on CiscoCatalyst switch access ports anduplinks/downlinks

3. Enables Cisco Catalyst strictpriority queuing for voice andweightedround robin queuing for data traffic

4. Modifies queue admission criteria

(i.e. CoS-to-queue mapping)5. Modifies queue sizes, as well as

queue weights where required

6. Modifies CoS-to-DSCP and IPprecedence to-DSCP mappings

28

For campus Cisco Catalystswitches, AutoQoS commandmacro enables the followingQoS features automatically:

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Central Site

Enabling QoS in the CampusPlatform Recommendations

Remote Site

Unified CMCluster

SRST

Router

Router/

Gateway

Cisco Catalyst 6500

Cisco Catalyst 4500

Cisco Catalyst 4000

Cisco Catalyst 4x00

Cisco Catalyst 3560, 3750

Cisco Catalyst 2950, 2960

Cisco IOSRouter SW NM

IP WAN

PSTN

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1. Building a Campus Network

2. Enabling QoS in the Campus3. Enabling QoS in the WAN


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G.729A: 25 ms

CODEC

Variable(Can Be Reduced

Using Priority

Queuing)

Queuing

Variable(Can Be Reduced

Using LFI)

Serialization

6.3 s/Km +Network Delay

(Variable)

Propagationand Network

2050 ms

Jitter Buffer

Enabling QoS in the WANElements That Affect End-to-End Delay

IP WAN


Unified CMCluster

SRSTRouter

PSTN

End-to-End Delay (Aim for < 150 ms)

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Time (msec)

0 100 200 300 400

CB Zone

Satellite Quality

Fax Relay, BroadcastHigh Quality

Delay Target for Voice (Total, Including Latency)

500 600 700 800

ITU G.114 Recommendation: 0150 msec One-Way Delay

Delay Starting Point for Video

QoS in the WANEnd-to-End Latency for Voice and Video

1. Video takes longer to encode/decode than voice2. Average is 150-ms encode and 150-ms decode = 300 ms

3. The audio is typically delayed to sync up with the video(except for VT advantage)

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QoS in the WAN: QoSConsiderationsBest Effort vs. Guaranteed Quality

Guaranteed Voice Quality Leased LinesFrame Relay

ATM

ATM/Frame Relay

IP-SEC V3PN

MPLS

Call Agents

BusinessCritical Calls

Best Effort Voice QualityDSL

Cable

WirelessInternet

VPN

Telecommuters

Road Warriors

Intra Company Calls

E bli Q S i h WAN

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Enabling QoS in the WANGeneral Guidelines

1. Use LLQ anytime VoIP over the WAN is involved

2. Traffic shaping is a requirement for Frame Relay/

ATM environments

3. Use LFI techniques for all links below 768 Kbps

Dont use LFI for any video-over-IP applications

4. TX-ring sizes may require modification5. Properly provision the WAN bandwidth

6. Call admission control is a requirement where VoIP callscan over-subscribe the provisioned Bandwidth

7. Use cRTP carefully

8. Map QoS from L3 (IP precedence or DSCP) to L2 (802.1p)at remote branches if switch is L2 only

QoS in the WAN:

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class-map class-defaultmatch any

class-map match-all voicematch ip dscp ef

Class-map match-all voice-controlmatch ip dscp af31 ; or CS3

!policy-map WANclass voice

priority percent 17

class voice-controlbandwidth percent 2

class class-defaultfair-queue

!interface Serial0/1ip address 10.1.6.2 255.255.255.0bandwidth 128no ip directed-broadcastservice-policy output WAN!

QoS in the WAN:Prioritizing Voice Traffic

LLQ

Classify

De-queue

2 2

3 3

class-map default = remaining

3 2 1 2 11128kbps

Class-Map Voice = 17%

Any Packet with DSCP = 46(PHB=EF) Gets Assigned to aClass that Will Get a High PriorityQueue with 17% Bandwidth

11Priority

Queue

CBWFQ

Low Latency Queuing Example

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CentralSite

Remote Sites

Frame Relay

or ATM

T1 T164

kbps T1

T1

CIR =64 kbps

Why Is It Needed?

Line speed mismatch

Remote to central siteoversubscription

To prevent bursting aboveCommitted Rate (CIR)

1

2

3 1 32

QoS in the WAN: Traffic Shaping

LineRate

R

Traffic Shaping Limits the TransmitRate to a Value (R) Lower than Line Rate

Without Traffic Shaping

With Traffic Shaping

Q S i th WAN

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QoS in the WANReducing Serialization Delay for Voice Packets

Link Type LFI Mechanism

Pt-to-Pt Links: MLPPPFrame Relay: FRF.12ATM: MLPPP over ATMATM/Frame-Relay SIW: MLPPP over ATM and FR

Note *LFI is not required for link speeds greater than 768kbps

Large Data PacketVoice Packet

214-ms Serialization Delayfor 1500 Byte Frame at 56 kbps

Before

Data Frag 1 Data Frag 2 Data Frag 3After

Link Fragmentation and Interleaving (LFI)

Voice Packet

QoS in the WAN

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Voice

Interleave

WFQ

Link Fragmentationand Interleave

Low Latency Queuing

PacketsOut

PacketsIn

Police

Video

QoS in the WANPacket Scheduling, Fragmentation and Interleaving

Best Effort

Signaling

TXRing

Critical Data

Layer 3 Queuing Subsystem Layer 2 Queuing Subsystem

PQ

PQ Packets Do Not Go through Fragmentation:on Low-Link Speeds, You Cannot Put Large

(i.e., Video) Packets in the PQ with VoicePackets; Therefore Video Traffic Not

Recommended for Link Speeds

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Link Capacity = (Min BW for Voice + Min BW for Video + Min BW for Data)/0.75

Voice Is Not FreeEspecially on Low-Speed LinksEngineer the Network for Data, Voice, and Video

QoS in the WANBandwidth Provisioning

Sum of Traffic = 75%

Link Capacity

Video

LLQ = 33%

Reserved

Voice/VideoControl

Data Routing,Etc.Voice

QoS in the WAN

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QoS in the WANProvisioning Bandwidth for Voice-Bearer Traffic

A More Accurate Method for Provisioning Is to Include

the Layer 2 Headers into the Bandwidth Calculations:

See Appendix for iLBC codec and SRTP bandwidth calculations

CODECSampling

RateVoice Payload

in BytesPackets per

SecondBandwidth per

Conversion

G.711/G722-64k 20 msec 160 50 80 kbps

G.711/G722-64k 30 msec 240 33 74 kbps

G.729A 20 msec 20 50 24 kbps

G.729A 30 msec 30 33 18 kbps

CODECEthernet14 Byes of

Header

PPP6 Bytes of

Header

ATM53 Bytes Cells witha 48-Byte Payload

Frame Relay4 Bytes

of Header

G.711/G722-64k at 50 pps 85.6 kbps 82.4 kbps 106 kbps 81.6 kbps

G.711/G722-64k at 33 pps 77.6 kbps 75.5 kbps 84 kbps 75 kbps

G.729A at 50 pps 29.6 kbps 26.4 kbps 42.4 kbps 25.6 kbps

G.729A at 33 pps 22.2 kbps 20 kbps 28 kbps 19.5 kbps

QoS in the WAN

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15 pps

30 pps

IFrame

10241518Bytes

IFrame

10241518Bytes

P and B Frames128256 Bytes

600 Kbps

32 Kbps

QoS in the WANVideo/Cisco TelePresence Bandwidth Variability

1. I frame is a full sample of the video

2. P and B frames use quantization viamotion vectors and prediction algorithms

Note: The Information in This Section Applies to BothCisco TelePresenceand Video Applications

QoS in the WAN

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128k = 153k

384k = 460k

512k = 614k

768k = 921k

1.5M = 1.8M

Video Data Rate andBandwidth Required

QoS in the WANCalculating Layer 2/3 Overhead for Video

1. Harder to calculate video bandwidthbecause payload size is variable

(video is bursty!)2. General rule of thumb is to add 20%

for all Layer 2/Layer 3 overhead

3. Call bandwidth is typically themaximum transmission bandwidthof the call; average is usuallymuch less

For More Information, see Video and Cisco TelePresence Sessions:

BRKVVT-2300 Designing and Deploying IP Video Telephony Networks

BRKVVT-2304 Cisco TelePresence Solution Architecture for the Enterprise

QoS in the WAN

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QoS in the WANProvisioning Bandwidth for Signaling Traffic

...

...

Please Refer to UCSRND 6.X for EncryptedCall Control Bandwidth

Centralized Call Processing

(As per 6.X SRND, No Encryption)

Number ofIP Phones,Gateways

SCCP ControlBandwidth

SIP ControlBandwidth

1 to 30 8 kbps 8 kbps

50 14 kbps 27 kbps

100 27 kbps 54 kbps

150 40 kbps 81 kbps

Distributed Call Processing

Number ofVirtual Tie Lines

Bandwidth

1 to 70 8 kbps

QoS in the WAN

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cRTPHeader

~24 Bytes

QoS in the WANProvisioning Bandwidth with Compressed RTP (cRTP)

1. Compresses RTP + UDP + IP headers (40 bytes) down to 24 bytes

2. Enabled on point-to-point linksimpacts router CPU

LinkHeader

IP HeaderUDP

HeaderRTP

Header

VoIP Packet

X Bytes20 Bytes8 Bytes12 Bytes

VoicePayload

X Bytes

CODEC

PPP6 Bytes of Header

without CRTP

PPP6 Bytes of Header

with CRTP

Percent

BandwidthReduction

G.711 at 50 pps 82.4 kbps 68 kbps 17.5%

G.711 at 33 pps 75.5 kbps 66 kbps 12.5%

G.729A at 50 pps 26.4 kbps 12 kbps 54.5%

G.729A at 33 pps 20 kbps 10.5 kbps 47.5%

QoS in the WAN

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QoS in the WANCisco IOS AutoQoS for WAN Links

1. Similar to AutoQoS inCisco Catalyst switches

2. Use AutoDiscovery to:

Determine WAN traffic typesand their offered bit rate

3. Use AutoQoS to:

Apply map classes to match on

QoS values/traffic typesQueue traffic types appropriately

Assign WAN queue bandwidthbased on traffic type

Mark or Re-Mark QoS

DSCP values

Assign QoS policy toWAN interfaces

IP WAN

PSTN

AutoDiscovery Cisco AutoQoS Policy

Application andProtocol-Types

Cisco AutoQoSClass-Maps

Match Statements

Offered Bit Rate

(Average and Peak)

Minimum Bandwidthto Class Queues,

Scheduling and WRED

*AutoQoS was introduced in 12.3(11)T

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WAN Call Admission Control (CAC)

Why Is It Needed?

Best Practices:

1. Use CAC to control the

number of calls allowed overthe WAN

2. LLQ Bandwidth = the numberof calls x bandwidth per call

3. Bandwidth per call iscodec specific

4. G711 @ 20mS samples =80kbps

5. G729 @ 20mS samples =24kbps

IP WANLink

IP WAN Links LLQ IsProvisioned for Two

Calls (Equivalent toTwo Virtual Trunks)

No Physical Limitationon IP Links; Third Call

Can Go Through, butVoice Quality of AllCalls Degrades

Call AdmissionControl Blocks Third Call

IP WAN

Router/Gateway CUCM

Note: Codecs that vary their bandwidth based on network conditions (e.g. packet loss) can be

problematic as WAN over-subscription can occur affecting the voice quality of all calls

Enabling QoS

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Enabling QoSQoS Approach Summary


Unified CMCluster

SRSTRouter

IP WAN

PSTN

Classification: Mark the Packets with a Specific Priority Denoting aRequirement for Class of Service from the Network

Trust Boundary: Define and Enforce a Trust Boundary at the Network Edge

Provisioning: Accurately Calculate the Required Bandwidthfor All Applications Plus Element Overhead

Scheduling: Assign Packets to One of Multiple Queues (Based onClassification) for Expedited Treatment through the Network

Enabling QoS

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Inline power

Multiple Qs

802.1p/Q

Fast linkConvergence

CampusAccess

Multiple Qs

802.1p/Q

Classification

Reclassification

CampusDistribution

Multiple Qs

802.1p/Q

Traffic Shaping

Link Efficiency(LFI, cRTP)

Classification

Reclassification

WANAggregation

SRSTRouter

Multiple Qs

802.1p/Q

Link Efficiency(LFI, cRTP)

Classification

Reclassification

Branch Router

Inline Power

Multiple Qs

802.1p/Q

Branch Switch

Enabling QoSOverall QoS Design Summary

IP WAN


Unified CMCluster

PSTN

BandwidthProvisioning

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1. Building a Campus Network




Overlaying Wireless LANs

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y gNon-Controller-Based Wireless

1. Layer 2 roaming requiresspanning at least two VLANsbetween wiring closet switches

Common Trunk or nativeVLAN for Access Points (APs)to communicate to WirelessDomain Service (WDS)

The Wireless Voice VLAN

2. Use an 802.1Q trunk for switchto AP connection

3. Different WLAN authentication/

encryption methods requiredistinct VLANs

Layer 2

Layer 3

Wireless

VLANs

Fast Secure Roam Using L2

L2Trunks

Data DataVoiceVoice


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DataVoice

y gController-Based WLAN: The Architectural Shift

1. Cisco WLAN controller andWireless Services Module(WiSM) provide for acentralized point to bridge all

traffic into the Campus2. Control and Data traffic is

tunneled to a centralizedcontroller (via Light Weight

Access Point Protocol LWAPP)

3. No longer a need to span aVLAN between closets (no STPloops)

4. No need for trunks between

APs and access layer switches

5. Details in Enterprise Mobility3.0 Design Guide atwww.cisco.com/go/srnd

Fast Secure Roam with No L2 Loop

WLAN Controllers

DataVoice

LWAPP LWAPP

WirelessVLANs

L2Trunks

WiSM


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y gWLAN Controllers and AP VLAN Considerations

1. Wireless VLANs should not beused for non-wireless traffic

2. LWAPP encapsulated traffic isrouted via default gateway on this

VLAN

3. Traffic is bridged on a proper VLAN(corresponding to the SSID) afterbeing LWAPP-decapsulated

4. APs management IP address isconfigured on the native/defaultVLAN

5. Define the native VLAN on theswitch port to match the AP

management/ default VLAN6. For more information, see Breakout

Session BRKAGG-3013 WirelessLAN Radio Spectrum ManagementBest PracticeUnique Native VLANs

WiSM

WLAN Controllers

Campus Core

The Elements ofU ifi d C i ti

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Media

Resources

UC

ProcessingAgentsGateway/

SurvivableRemote

PSTN/IP

Gateway

UC

EndpointsComms

Endpoints

PSTN

WANAggregation

Router

BranchRouter


Campus

Branch

IP WAN

AccessSwitch

AccessSwitch

Conf

Voice Mail/Unified

Messaging

Web /Audio/Video

Conferencing

XMLPhone

Services

LDAPDirectory

GKGKMTPMTP

XcodeXcode

ConfConf

SiSiSiSiSiSi

SiSiSiSiSiSi

UCApplications

UC Infrastructure

What We Have Uncovered So Far


A d

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Agenda

Introduction






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Agenda

Part 1

1. Unified CM Clustering

2. Deployment Models

3. Signaling Protocols

4. Network Services

5. Basic Call Processing

6. Failover and Redundancy

Part 2

1. Media Resources

2. Telephony Gateways andFax

3. Cisco Unified BorderElement

4. Survivable RemoteSite Telephony

5. Unified CM Express

6. Call Admission Control

7. Dial Plan


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Unified CM Clustering: MCS Servers

1. Unified CM is installed on a Cisco Media ConvergenceServer (MCS)

2. Unified CM 4.x: Cisco Windows OS (two CDs) + UnifiedCM application

3. Unified CM 5.x/6.x/7.x: Cisco appliance-based OS andUnified CM application (one DVD)

4. First server in cluster must be the Publisher server

+ =


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Call Processing Servers (Max. 8)

ccm.exe ccm.exe

ccm.exe ccm.exe

CTI Manager

MoH Server

TFTP Server

Publisher

Software Conferencing

MS-SQL/IDS Subscribers (Max. 19)

Database (DB)Replication

Unified CM Cluster

Unified CM Clustering: DB Replication and ICCS

Unified CM 4.x: DB=MS-SQL | OS=MS W2K Server

Unified CM 5.x/6.x/7.x: DB=IBM-IDS | OS=Linux

DBDB

DBDB

DBDB

DBDB

DBDBDBDB

DBDB DBDBICCSICCS

DBDB

Unified Communications InfrastructureU ifi d CM Cl t i 6 /7 U F i F t

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Publisher Database(All Data Writable)

Unified CM 6.x Cluster

DB Replication

DB Subscribers (User Facing Features Are Writable)

Bidirectional User Facing Feature Replication

Logically Unidirectional DB Replication from Publisher

Unified CM Clustering: 6.x/7.x User Facing Features

User Facing Features:

1. Call Forward All

2. Message Waiting Indicator

3. Privacy Enable/Disable

4. Device Mobility

5. Extension MobilityLogin/Logout

6. Do Not DisturbEnable/Disable

7. Hunt Group Login/Logout

8. CTI CAPF status for enduser

9. Credential hacking andauthentication

Sub

Sub Sub

SubDBDB DBDB

DBDBDBDB

DBDB

Unified Communications Infrastructuref C C

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Unified CM Clustering: Properties and Rules

1. The cluster appears as one entity, with asingle point of administration (the publisher)

2. Several functions can be collocated on the sameserver, depending on cluster size and server type

3. Maximum of 19 subscribers per cluster (20 servers in

a cluster including the publisher)4. Maximum of eight call processing servers per cluster

5. Maximum of 7500 IP Phones per Cisco Unified CM

server (server platform dependant)

6. Maximum of 30,000 IP Phones per Cisco Unified CMcluster (server platform and configuration dependant)

Unified Communications InfrastructureAgenda

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Agenda

Part 1




4. Network Services



Part 2

1. Media Resources






7. Dial Plan

Unified Communications InfrastructureD l t M d l

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Deployment Models

1. Physical Location of Unified CM cluster Servers

2. Physical Location of Unified CM cluster IP Phones

3. Number of Unified CM clusters

These Deployment Models Are Call Processing-Based Models Dictated By:

Deployment ModelsSingle Site

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Single Site

1. Unified CM,applications and DSPresources at samephysical location

2. Supports up to30,000 SIP or SCCP

phones per cluster3. PSTN used for

all external calls

PSTN

Applications(VMail, IPCC, MP)

Unified CM Cluster

Deployment ModelsCentralized Call Processing

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Centralized Call Processing

1. Unified CM cluster at central/HQ site

2. Applications and DSP resources can be centralized or distributed

3. Supports up to 30,000 SIP or SCCP phones per cluster

4. If WAN is busy, transparent use of PSTN (Automated Alternate RoutingAAR)

5. Survivable Remote Site Telephony (SRST) for remote branches

6. Maximum 1000 sites per cluster (500 branches before Unified CM 6.x)

PSTN

IP WAN

Headquarters

Branch A

Branch B

SRST-EnabledRouters


Unified CMCluster

Deployment ModelsDistributed Call Processing (Unified CM-Unified CM Model)

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Distributed Call Processing (Unified CM Unified CM Model)

1. Unified CM, applications, and DSPs located ateach site

2. Up to 30,000 SIP or SCCP phones per cluster

3. 100+ sites

4. Transparent use of PSTN if IP WANunavailable

5. Each cluster can be single site orcentralized call processing topology

Gatekeeper

Regional Branch A

Regional Branch B

Headquarters

IP WAN

PSTN


Unified CMCluster

Unified CMCluster

Applications

Applications

Unified CMCluster GKGK

GKGK

Deployment ModelsDistributed Call Processing (Unified CM-Unified CME Model)

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Distributed Call Processing (Unified CM Unified CME Model)

1. Unified CM, applications located at HQ orBranch site

2. DSP resources located at each site

3. Up to 30,000 phones per Unified CM cluster

4. Up to 240 phones per Unified CME

5. 100+ sites

6. Transparent use of PSTN if IPWAN unavailable

Gatekeeper

Regional Branch A

Regional Branch B

Headquarters

IP WAN

PSTN


Cisco UnifiedCommunicationsManager Express

UnifiedCME

GKGK

Unified CMCluster

Deployment ModelsClustering over the WAN (CoW)

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DistanceSan Jose San Francisco

Clustering over the WAN (CoW)

1. Unified CM servers in a cluster separated by WAN for spatial redundancy

2. Applications may be located at each site, thus separated by WAN

3. Single point of administration, feature transparency (e.g. Extension Mobility),

unified dial plan

4. Maximum 40-ms round-trip delay between any two Unified CM across the WAN

5. 900 kbps bandwidth for each 10,000 BHCA between sites

6. Maximum of eight active locations

Increased to

80-ms RTTin 6.1

B/W RequiredIncreased in

6.1

Unified CM Cluster

Voice Mail Voice Mail


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Agenda

Part 1




4. Network Services



Part 2

1. Media Resources






7. Dial Plan

Unified Communications InfrastructureSignaling Protocols: Unified CM as Protocol Translator

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Signaling Protocols: Unified CM as Protocol Translator

SCCP H.323

Gateways

AnalogPhones

Wireless IP Phones

IP Phones

Analog Phones

PC-Based

IP Phones

Gateways

IP Phones

SIP Networks

Video

Terminals

Gateways

AnalogPhones

ApplicationsServers

(JTAPI/CTI)Call Agents

CTI/Q

BE

SIP

Session Initiation Protocol

Skinny Client Control ProtocolITU-T H.323 Standard

Computer Telephony Integration/Quick Buffer Encoding

MGCP

Media Gateway Control Protocol

Telepr

esence

Unified Communications InfrastructureSignaling Protocols

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Cisco Unified Communications Integrates Rich, Native SIP andSIMPLE Support on Both Line-Side and Trunk-Side Interfaces withIntegrated Presence on Phones and Applications While MaintainingSeamless Inter-Working with Existing H.323, MGCP, SCCP,TAPI/JTAPI and Q.SIG Protocols

Cisco UnifiedPersonal

Communicator

Unified

Messaging

CTI Apps

Gateways

Rich-MediaConferencing

Cisco UnifiedPresence Server

Cisco and3rd-party Phones

Soft

Phones

VideoEndpoints

Unified CME

Microsoft

LCS

IBMSametime

Unified CM 5.x/6.x

Unified CM 5.x/6.x

Carriers/Other Vendors

PBXs

SCCP

MGCP

H.323CTI

SIP/SIMPLE

CSTA over SIP

Conf/ Xcode

DSP Resources

g g


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Agenda

Part 1




4. Network Services



Part 2

1. Media Resources






7. Dial Plan

Unified Communications InfrastructureNetwork Services: IP Phone Bootup Process

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Network Services: IP Phone Bootup Process

1. Inline Power (ILP)

Inline Power Initialization

2. Cisco Discovery Protocol (CDP) or Link LayerDiscovery Protocol-Media Endpoint Discovery(LLDP-MED)

ILP Negotiation, Voice VLAN ID

3. Dynamic Host Configuration Protocol (DHCP)

IP Assignment, TFTP Server Allocation, DNS (optional)

4. Trivial File Transfer Protocol (TFTP)

Configuration File, IP Phone Firmware

Unified Communications InfrastructureNetwork Services: Inline Power

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On Phone: Mute, Headset, Speaker Buttons Are Illuminated

Inline Power

AC Low Frequency Fast Link Pulse (FLP)

Reflected FLP

CiscoCatalystSwitch

Cisco Prestandard

802.3af

DC Current

Return Current (Resistive Detection)

DC Current

Attenuated DC Current (Classification)

Unified Communications InfrastructureNetwork Services: CDP or LLDP-MED

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1. Phone displays:Configuring VLAN

2. Phone settings:Settings=>NetCfg=>Operational VLAN ID

Inline Power ProvidedCiscoCatalyst

SwitchCDP/LLDP-MED(ILP, Voice VLAN, Ext. Trust Value, PC)

LLDP-MED is supported as of IP Phone Firmware 8.3(3)

LLDP-MED and CDP White Paper:http://www.cisco.com/en/US/technologies/tk652/tk701/technologies_white_paper0900aecd804cd46d.html

Unified Communications InfrastructureNetwork Services: DHCP

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1. Phone displays:Configuring IP(DNS is optional)

2. Phone settings:Settings=>NetCfg=>DHCP ServerSettings=>NetCfg=>IP AddressSettings=>NetCfg=>TFTP Server X

CDP/LLDP Neighbored

DHCP Req

DHCP Rsp (IP Add, Def-GW, TFTP, DNS*)DHCPServer

CiscoCatalyst

Switch

DHCP Request Must Be Made in

the Correct VLAN to Place the

Phone in the Correct Subnet!!

Inline Power Provided

Option 150 or Option 66

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75

CM Group: UCM1UCM2

Publisher

UCM1

UCM2

UCMx

TFTP

Device Pool

TFTP: GET Configuration File(s) for MAC

Phone Configuration, Firmware Download(If Required)

1=UCM1: 10.1.1.12=UCM2: 10.1.1.2

Registration(SCCP,SIP)

Backup Link

Unified CMCluster

MAC Address:

001956A6A7ED


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76

Part 1




4. Network Services



Part 2

1. Media Resources






7. Dial Plan

Unified Communications InfrastructureBasic Call Processing: Single Site Deployment Model

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77

Signaling Leg 1

Dialed Digits

Alerting (Ringback)

Connect Media

Sign

alin

gLe

g2

Alert(R

ing)

Offho

ok

Conn

ectM

edia

Dial Plan Lookup

Media(RTP Stream)

IP Phone A

IP Phone B

Unified CM

Offhook

IP Phone to IP Phone Example

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78

Signaling Leg 1

Dialed Digits

Alerting (Ringback)

Connect Media (OLC)

Signali

ngLe

g3

Alert(Ring

)

Offho

ok

Conn

ectMedia(

OLC)

Dial Plan Lookup

Media(RTP Stream)

IP Phone A

IP Phone B

Unified CMCluster

Offhook

ICCS

Intra-Cluster IP Phone to IP Phone Example

Unified Communications InfrastructureBasic Call Processing: Centralized Deployment Model

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79

1. Call Processing is essentially the same in thisdeployment model as in the single site case; IPmakes the technology more topology independent

Unified CM

IP WAN

IP Phone A

IP Phone B

SignalingLe

g1

SignalingLeg2

Media

Dial Plan Lookup

IP Phone to IP Phone Example

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80

IP Trunk

IP WAN

Unified CMCluster 1

Unified CMCluster 2

Media

Sig

nalin

gLeg

1Signa

ling

Leg

3

Signaling Leg 2Dial Plan Lookup

Call Setup

Dial Plan Lookup

Alerting

Connect

IP Phone A IP Phone B

Inter-Cluster IP Phone to IP Phone Example

Unified Communications InfrastructureBasic Call Processing: Distributed Deployment Model

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IP WAN

Unified CMCluster 1

Unified CMCluster 2

Media

Sig

naling

Leg

1Sign

aling

Leg

5

Signaling Leg 3

Dial Plan LookupDial Plan Lookup

IP Phone A IP Phone B

GK

Signalin

gLeg

2

DialP

lanRe

s/CAC

SignalingLeg4

DPRes/CAC

Inter-Cluster with Gatekeeper IP Phoneto IP Phone Example

Unified Communications InfrastructureBasic Call Processing: Cluster over WAN Deployment Model

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Signaling Leg 1 Signaling Leg 2

Dial Plan Lookup

Media(RTP Stream)

IP Phone B

Unified CMCluster

ICCS

IP Phone A

IP WAN

Intra-Cluster IP Phone to IP Phone Example


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Part 1




4. Network Services



Part 2

1. Media Resources





6. Call Admission Control7. Dial Plan

Unified Communications InfrastructureFailover and Redundancy: Server Redundancy

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Directory Services

Call Processing

CTI/QBE I/F

SCCP I/F

MGCP I/F

H.323 I/F

Software MTP


Music on Hold

ActiveUnified CM Server

Cisco UnityVmail Server

JTAPIIP-IVR

IP Phones

Gateways

DSP Resources

Conferencing

DSP ResourcesTranscoding

Intra-ClusterCommunications

(ICCS)

SIP I/F

Unified CM Subscriber

Unified CM Subscriber

Failed TFTP

Directory Services

Call Processing

CTI/QBE I/FSCCP I/F

MGCP I/F

H.323 I/F

Software MTP


Music on Hold

SIP I/F

TFTP

XcodeXcode

ConfConf

Unified Communications InfrastructureFailover and Redundancy: 1:1 vs. 2:1 Redundancy

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1. Cost-efficient redundancy

2. High Availability

during upgrades3. Maximum of 10,000 backup

registrations/server

1. Load-sharingredundancy

2. High Availabilityduring upgrades

3. Faster failover

1 to2500

2501 to5000

Backup

2:1 Redundancy Scheme 1:1 Redundancy Scheme

1 to1250

1251 to2500

2501 to3750

3751 to5000

MCS 7835 Supports 2500 Phones/Server

Unified Communications InfrastructureFailover and Redundancy: 1:1 Redundancy Example

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1. MCS 7845 supports 7500phones/server

2. Load-share between primaryand backup servers

Backup

Publisher and

TFTP Server(s)

To 7,500 IP Phones To 15,000 IP Phones To 30,000 IP Phones

Publisher andTFTP Server(s)Publisher and

TFTP Server(s)

1 to 3750: Primary3751 to 7500: Backup

13750

3751 to7500

750111,250

11,25115,000

15,00118,250 18,25122,500

22,50126,250

26,25130,000

3751 to 7500: Primary

1 to 3750: Backup

13750

37517500

750111,250

11,25115,000

Phone Set 1 Phone Set 2

Backup

Primary

Primary

Failover and RedundancyDatabase Resiliency (Unified CM Version 6.x)

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Publisher Database(All Data Writable)

Unified CM 6.x/7.x Cluster

DB Replication

DB Subscribers (User Facing Features Are Writable)

Bidirectional User Facing Feature Replication

Logically Unidirectional DB Replication from Publisher

User Facing Features:

1. Call Forward All

2. Message WaitingIndicator (MWI)

3. Privacy Enable/Disable4. Device Mobility

5. Extension MobilityLogin/Logout

6. Do Not Disturb Enable/Disable

7. Hunt Group Login/Logout8. CTI CAPF status for end user

9. Credential hacking andauthentication

DBDB DBDB

DBDBDBDB

DBDB

Unified Communications InfrastructureFailover and Redundancy: Media Survivability

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Unified CM Cluster1. Media does not fail duringloss of connectivity toUnified CM

2. No Services (e.g. hold,transfer, etc.) whenUnified CM not available

3. Once the call is complete,

phones re-register tobackup Unified CM

Media

LinkF

ailure

SignalingTraffic

SignalingTraffic

SCCP IP Phone SIP IP Phone

N l O ti

Unified Communications InfrastructureFailover and Redundancy: Survivable Remote Site Telephony

U ifi d CM

WAN F il

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Normal Operation

Central Site

Branch Site

SRSTCapableRouter

IP WAN

PSTN

Signaling Traffic

1. IP Phones have SRST router IP as the last option in their CM GROUP configuration

2. Support for both SIP and SCCP IP Phones

3. With SRST, only a subset of features are available to the phones (DID, DOD, call hold,transfer, speed dial, caller ID, etc.)

4. H323 PSTN GW connectivity option during failure modes via VoIP/POTS dial-peers; MGCPGWs require the MGCP Fallback to H323 feature

Voice Traffic

Signaling Traffic

Voice Traffic

Unified CMCluster

Applications

WAN Failure

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Infrastructure

Part 2


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Part 1




4. Network Services



Part 2

1. Media Resources



4. Unified Survivable RemoteSite Telephony


6. Call Admission Control7. Dial Plan

Media ResourcesConferencing, Transcoding, Music on Hold

CiIVR

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1. Conference Bridge

DSPs needed for multi-codec conferences

2. Media Termination PointMedia Termination

DSPs optional

3. Transcoding

DSPs needed to transcodemultiple CODEC types (e.g.,G.711 to G.729)

Automatic codec selection

4. Music on HoldMultiple source types possible

(centralized or branch-based)

CiscoUnifiedCMCluster

IP WAN

...

IVR

ConferenceBridge

MTP

Transcoder

Musicon Hold

ConfConf

XcodeXcode

MTPMTP

PSTN

Media Resource Group Listsand Media Resource Groups

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1stChoice

2ndChoice

User NeedsMedia

Resource

1st

Choice

2nd

Choice

2nd

Choice

1st

Choice

Assigned to DeviceDirectly or viaDevice Pool

MediaResourceManager

MediaResourceGroup List

MediaResource

Group

MediaResource

1

MediaResource

1

MediaResource

2

MediaResource

3

MediaResource

Group

Media ResourcesMRGL and Device Association

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Site B

Site A

MRGLA

MRGA

MRGLB

MRGB

Device PoolA

CM Group

Date/Time Group

Region

Media Resource Group List

Device PoolB

CM Group

Date/Time Group

Region

Media Resource Group List

Assign a MRGL Directlyto the Device Take aHigher Priority thanDevice-Pool Based

Configuration

For Groups of Devices that DontNeed Special Media Resources or

Cant Be Assigned a MRGL DirectlyAssign the MRGL via the Device Pool

MediaResources

MediaResources

MRM Resource Selection

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1. MRGL will contain MRGs

2. MRGs are read in order as they were configured

(MrgA, MrgB, MrgC, etc.)

3. MRM will walk through the MRG in this order, MrgAfirst, if resource in MrgA is exhausted then MrgB, ifresource in MrgB is exhausted then MrgC

4. The resource in each MRG is round robin based onthe most available capacity of each device

Group Resources by Type

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A B

C

RTP

ResultUse All Software Conference

Resources First, then HardwareConference Resources

I Would Like to Conference toPhone C. Is There Any

Conference ResourceAvailable?Software MRG

MTP1MTP2SW-CONF1SWCONF2

Hardware MRG

XCODE1XCODE2HW-CONF1HW-CONF2

Resource_List

1

2

3

MOH MRG

MOH1MOH2

Group Resources by Location

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ResultDevices Use

Resources at TheirLocation First

Dallas MRG

XCODE1HW-CONF1MOH2

Hub_MRGMTP1MTP2MOH1SW-CONF1SW-CONF2

SanJose_MRGXCODE2

HW-CONF2MOH3

Dallas_List

1

2

3

SanJose_MRG

XCODE2HW-CONF2MOH3

Hub_MRGMTP1MTP2MOH1SW-CONF1SW-CONF2

Dallas MRGXCODE1

HW-CONF1MOH2

SanJose_List

1

2

3

Dallas

San Jose

Restrict Accessto Conference Resources

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MTP MRGMTP1

MTP2

CONF MRGSW-CONF1SWCONF2HW-CONF1

HW-CONF2

MOH MRGMOH1MOH2

Resource_List

1

2

3

XCODE MRGXCODE1XCODE2

4

MTP MRGMTP1

MTP2

MOH MRGMOH1MOH2

NO_CONF_List

1

2

3XCODE MRGXCODE1XCODE2

ResultDevice Cannot Use

Any ConferenceResources

A

Media ResourcesCentralized Conferencing Resources

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CentralSite

Remote Site

CiscoUnified CMclusterPSTN

Conf

External caller X calls Ano voice across WAN

A conferences B in

A

B

X

Three voice streams across WAN

1.No media survivability if WAN goes down

IP WAN

Media ResourcesDistributed Conferencing Resources

Cisco MRGL

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A

B

MRG = Media Resource GroupMRGL = Media Resource Group List

DevicePool

A

B

DevicePool

1. Br12. HQ13. HQ2

MRGL

1. Conference between A, B, and XNovoice across WAN

2. Requires extra hardwareat branch

3. Only 3-way conferencing in CUCMfallback mode

HQBranch

Unified CMCluster

IP WAN

PSTNX

Conf

Conf

MRG=HQ1

Conf

Conf

MRG=HQ2

Conf

MRG=Br1

1. HQ12. HQ2

MRGL

X

Media ResourcesCentralized vs. Distributed DSPs

CiscoUnified CMCluster

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CentralSite

Branch

IP WAN

A

B

X

DistributedDSPs

MRGConf

CentralSite

Branch

PSTN

Conf

A

B

MRG

Conf

Conf

MRG

Conf

Conf

CentralizedDSPs

$ Bandwidth vs. $ Hardware

Cluster

CiscoUnified CMCluster

IP WAN

PSTN

Intelligent Bridge Selection (New in 7.0)

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Problem: If a video bridge is defined as a primary media resource, thenUnified CM will use that bridge whether or not video is involved.Customers have to provision enough video bridge ports to supportboth.

Solution: Unified CM will search endpoints of an ad hoc conference forvideo capability at the start of the conference

If 2 (configurable) or more conference participants are video enabled,a video bridge will be assigned

If only 1 or none conference participants are video, an audio bridgewill be assigned

If no video bridge ports are available, then an audio bridge will beassigned

If not enough bandwidth for video, video bridge is still allocated butconference will fallback to audio only

Supported intra-cluster, SIP and H.323 ICTs

Endpoint must be configured and enabled (e.g. CVTA with camerainstalled)

Applies to Conference, Join and CBarge, not Meet-Me nor Barge

Media ResourcesMedia Termination Point and Transcoder

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1. Terminates media streams (same codec type)

2. Transrating of media streams (20ms 30ms)

3. H.323 Outbound FastStart (vs. slow start)

4. SIP outbound early-offer (vs. delayed-offer)

5. DTMFRelay

6. Enhanced version of MTP resource

7. Transcoder = converts from one codec to another

Codec BCodec A

MTPMTP

XcoderXcoder

Media ResourcesDSP Platform Recommendations

CiscoUnified CM

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NM-HDV

NM-HDV2

ISR (onboard)

WS 6608 (32 parties)

CMM (128 parties)

NM-HDV2 (eight parties)

Hardware CFB

Software CFB

Central SiteRemote Site

Unified CMCluster

ConfConf ConfConf

PSTN

IP WAN

Media ResourcesMoH Configuration: Audio Source and Server Selection

The MoH Stream that an Endpoint Receives IsD t i d b C bi ti f th F ll i

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The Configured User/Network Hold Audio Sourceof the Endpoint/Network Resource Initiating

the Hold Event

and

The Configured Media Resource Group List

of the Endpoint Being Placed on Hold

Determined by a Combination of the Following:

Media ResourcesMoH Audio Source and Server Selection

MRGL B

MRG B A di 1

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MRGL A

MRG A

MOH A

MRGL A

MRG B

MOH B

User Hold Audio Source = Audio-source4

Media Resource Group List = MRGL A

Phone A

User Hold Audio Source = Audio-source2

Media Resource Group List = MRGL B

Phone BHold

RTP

Audio-source1

Audio-source2

Audio-source3

Audio-source4

Audio-source1

Audio-source2

Audio-source3

Audio-source4

Audio-source2

Audio-source2

Media ResourcesMoH Configuration Multicast Addressing

1 C fi lti t M H t lti t

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1. Configure multicast MoH sources to use multicastgroup addresses in the range:

239.1.1.1 to 239.255.255.255

2. Configure multicast MoH sources to increment onIP address not port number

Increment on IP Address for Two Reasons:

1. Cisco IP Phones Have No Concept of Multicast PortNumbers

2. IP Routers Route Multicast Traffic Based on MulticastAddress Not Port Numbers

Media ResourcesMulti-Site Centralized: MoH from Central Server

Phone B

CiscoUnified CM

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PSTN

Headquarters

Branch A

Branch B

SRST-EnabledRouter

Phone A

Phone D

Phone C

If MoH Stream Is Multicast then the Stream Will Be Allowed

If MoH Stream Is Unicast then the Stream Will Be Rejected

OversubscribedWAN Bandwidth

XRTP

Cluster

Only Unicast MoH Streams Are Tracked by Locations-Based CAC

Location Branch B

Bandwidth = 24 Kbps/1 callLocation Branch B

Bandwidth = 0 Kbps/0 Calls

IP WAN RTP

Hold

Media ResourcesCentralized Multi-Site: Mcast MoH from Router Flash

Multicast Address: 239.1.1.1

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1. Stream multicast MoH from Branch router flash

2. Works whether branch is operating in Unified SRSTmode or not

PSTN

IP WANHeadquarters

Branch A

Cisco UnifiedCM Cluster

SRST-EnabledRouter

Hold RTP

Phone B

Max Hop (TTL) = 1or

ACL to Stop Forwarding

Multicast Address: 239.1.1.1RTP Port: 16384

Phone A

X

Media ResourcesMusic on Hold: Server Configuration

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Maximum Number of

Streams (Affects Capacity)

Location of MoH Server;Required for CAC

Enables Multicast Support

Media ResourcesCentralized Multi-Site: Multicast MoH from Router Flash

1 Configuration for multicast MoH from branch

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1. Configuration for multicast MoH from branchrouter flash:

2. Even if not using SRST, a minimum of one max-dn

and one max-ephones must also be configured

3. Stream multicast MoH from flash whether in Unified

SRST mode or not

4. Configuration is the same in either case

SRST-router (config)# call-manager-fallbackSRST-router (config-cm-fallback)# moh flash-audio-file.au

SRST-router (config-cm-fallback)# multicast moh 239.1.1.1 port 16384 route 10.1.1.254

SRST-router (config-cm-fallback)# max-dn 1

SRST-router (config-cm-fallback)# max-ephones 1

Media ResourcesMoH Multiple Fixed/Live Audio Sources

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Cisco Unified CMCluster with Dedicated

MoH Server

Phone BPhone A

Central Site

Hold

RTP

Media ServerRadio Station

X

Multicast Address: 239.1.1.1RTP Port: 16384

Max Hop (TTL) = 1orACL to STOP Forwarding

Media Resource Key Takeaways

1 CFB MTP XCODE MOH are media resources

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1. CFB, MTP, XCODE, MOH are media resources

2. Media ResourceMRGMRGL

3. Load Balance (round-robin) Similar Media Resourceswithin an MRG

4. MRM walks through MRG in order top-down

5. Next MRG in MRGL is used required resource isexhausted or has failed (unregistered)


Part 1 Part 2

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Part 1


2. Deployment Models3. Signaling Protocols

4. Network Services

5. Basic Call Processing6. Failover and Redundancy

Part 2

1. Media Resources






7. Dial Plan

Cisco Unified CM

GatewaysGateway Selection Criteria

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PSTN

Router/

Gateway

Cisco Unified CM

IP WAN

1. Voice port density requirements

2. Signaling protocol (H.323, MGCP, SIP, etc.)

3. Support for required PSTN signaling types

4. Support for required WAN interfaces and QoS

GatewaysH.323

TDM IP

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H.245

1. All PSTN signaling terminates on gateway

2. H.225 communication between gateway and

Cisco Unified CM3. H.323 is a peer-to-peer protocol: each side

can make decisions

Framing

PRI Layer 3Layer 2

Cisco Unified CM

PSTN H.225

GatewaysSIP

TDM IP

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1. All PSTN signaling terminates on gateway

2. SIP communication between gateway and

Cisco Unified CM3. SIP is a peer-to-peer protocol: each side

can make decisions

Framing

PRI Layer 3Layer 2

PSTN SIP over UDP/TCP/TLS

Cisco Unified CM

GatewaysMGCP: Q.931 Backhaul

TDM IP

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1. Framing and layer 2 signaling terminates at the gateway

2. Layer 3 signaling is backhauled to the Cisco Unified CM

3. MGCP is a client-server protocol: all call-related decisionmaking is done by the server

4. MGCP 0.1 with Cisco Unified CM only

Framing

PRI Layer 3Layer 2

Q.931 Backhaul over TCPPSTN MGCP over UDP

Call Signaling Cisco Unified CM

The Power of Cisco IOS Dial-Peers:H.323 and SIP

IPPSTNdp 1 voip

dp 2 voip

dp 10 pots

dp 11 pots

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Dial-Peers Allow You to:1. Switch calls intelligently if required (interpret the dial plan)

2. Digit manipulation (called, calling and numbering plan)

3. Failover (preferences) to alternate destinations

4. Load balancing

5. Video ISDN switching

6. Insert applications into the call path: TCL/VXML

Build support for signaling variations (e.g. CLID on T1 CAS)

Hookflash trunk release on FXOVXML call control for call centers

Redistribute calls-in-q for CVP

AA in the GW

dp 3 voipdp 12 pots

These CapabilitiesDo Not Exist for

MGCP-Controlled GWs

Protocol Deployment Considerations

Large/CampusSites

Small/BranchSites

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1. MGCP

2. High-density GWs

3. Dedicated GW platforms

4. Caller ID/name

5. Digital TDM protocol

6. QSIG connectivity

7. Other considerations

1. H.323/SIP

2. Low-density

3. Dual purpose

4. Caller ID on analog FXO

required

5. Mixes PSTN TDM protocols

6. CVP/VXML application control


Sites Sites

Protocol Deployment Considerations

Large/CampusSites

Small/BranchSites

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1. Characteristics of larger site(s)often best served by MGCP

2. High-density GWs to PSTN,often PRI

3. Dedicated GW platforms

4. Caller ID/name delivery required

5. Digital TDM protocol (often PRI)6. QSIG connectivity (with

supplementary services) tolegacy PBXs required


NFAS is H.323/SIP only

Very high density GWs suchas T3 (5x00) are H.323/SIP only

1. Characteristics of branch site(s)often best served by H.323/SIP

2. Low-density GW to PSTN,often analog

3. GW and router features used onsame platform (integrated access)

4. Caller ID on analog FXO required

5. Mixes of PSTN TDM protocolsrequired (FXO, A-DID, BRI,Frac-PRI)

6. CVP/VXML application control

7. Other considerationsCan mix H.323 and MGCP on the

same GW (not on same voice port)

H.323 dial-peers are needed anywayfor MGCP GW Fallback

Protocol and Platform Summary

Gateway Platform

Line Side Trunk Side

SCCP (FXS) H.323 SIPMGCP

(CUCM)

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VG224 Yes Yes Yes Yes

VG248 Yes No No No

1751/60 No Yes Yes Yes

1800 Yes* Yes Yes Yes*

2600XM, 2691 No Yes Yes Yes

2800 Yes Yes Yes Yes

3700 No Yes Yes Yes

3800 Yes Yes Yes Yes

5x00 No Yes Yes No

7x00 No Yes Yes No

Cisco Catalyst6K CMM

No Yes Yes Yes

GatewaysProtocol and Platform Recommendations

Cisco

Unified CMCluster

SRST

PSTN

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MGCP, SIP, H.323

Standalone, Router-integrated

Platforms:WS-X6608, CMM

26XX, 28XX37XX, 38XX

H.323, SIP, MGCP fallbackto H.323

Standalone, Router-integrated

Platforms:

17XX, 18XX26xx, 28XX

37xx, 38xx

Central SiteRemote Site

SRSTRouter

Router/Gateway

IP WAN

GatewaysFax Pass-Through

T.30 Signaling +Modulated Data

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1. No demodulation of fax traffic (like a VoIP call)

2. Recommendation: hard-code codec to G.711for call admission control

3. When a fax call is detected:

Echo cancellation is disabled

Jitter buffer size is increasedVAD is disabled

4. Group Three (9600 kbps)best case 14,400 kbps

IPNetwork

GatewaysCisco Fax Relay

T.30 T.30Demodulated Data

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1. Cisco fax relay is negotiated over the media stream

in-bandCisco Unified CM handles it like a voice call2. T.30 is demodulated at the inbound gateway

3. Demodulated data is sent to the outbound gateway formodulation

4. Maximum speed: 14,400 kbps with G.711

IPNetwork

http://www.cisco.com/univercd/cc/td/doc/product/voice/c_access/fxmdmnt.htm#xtocid5

GatewaysT.38 Fax Relay

T.30 T.30T.38 over H.323/SIP/MGCP

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1. T.38 fax gateways provide the following functions

Demodulation of incoming T.30 fax signals at the transmitting gateway (T.30 is thestandard procedure for fax transmission in the PSTN)

Translation of T.30 fax signals into T.38 Internet Fax Protocol (IFP) packets

Exchange of IFP packets between the transmitting and receiving T.38 gateways

Translation of T.38 IFP packets back into T.30 signals at the receiving gateway

2. T.38 Fax Relay Call Control

The T.38 fax relay feature can be configured for H.323, Session Initiation Protocol (SIP),and Media Gateway Control Protocol (MGCP) call control protocols

IPNetwork

http://www.cisco.com/en/US/docs/ios/12_4t/voice/cisco_ios_fax_and_modern_services_over_ip_a

pplication_guide/638.html


Part 1 Part 2

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2. Deployment Models3. Signaling Protocols

4. Network Services



1. Media Resources






7. Dial Plan

Cisco Unified Border Element(Formerly Cisco Multi-Service IP-to-IP Gateway)

1. A Border Element is an essential component that allows the network to provide services forinterconnecting IP based communications

2. Examples: SIP Trunk interconnects; business-to-business CTS

3. Co-existence with other features such as MTP, Unified SRST, TDM GW

CUBECUBE

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SessionManagement

Inter-working Security

Demarcation

H.323 to SIPSIP to SIPSIP Profiles and Variants

Cisco IOSFirewall Integration

RTP Media Validation

Signaling Protection

Call Admission ControlIP QoS/SLA

Fault IsolationCall AccountingTopology Hiding Cisco Unified

BorderElement

Cisco Unified

BorderElement

Cisco Unified Border ElementSimplified Architecture

Media Flow-Through Generates Two IP Call Legs

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Media Bypasses the CUBE

Media Flow-Around

Signaling Leg: 1

Media Leg: 1 Media Leg: 2

Signaling Leg: 2

Signaling Leg: 1 Signaling Leg: 2

CUBECUBE

CUBECUBE

Cisco Unified Border ElementVoice Call Support

In Leg Out Leg Support

Fast Start Fast Start Bi-Directional

H.323-H.323

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Slow Start Slow Start Bi-Direc

TECUCT-1001

Documents

Transcript of TECUCT-1001