Perkongsian Maklumat

Perkongsian Maklumat Rangkaian USMNetBahagian Infostruktur

06-07/05/2008

Ahmad Fadhlul Irham YusoffE-mail: [email protected]

Abdul Ghani Abdul RahmanE-mail: [email protected]

Objectives Of The Class:

At the end of this lesson you should be able to understand:Network IntroductionType Of NetworkNetwork TopologyNetwork ComponentHow Network OperateNetwork Application & FacilitiesNetwork Threats & SecuritiesNetwork TroubleshootingQ & A Open Session

Internet & Network IntroductionObjectives Of The Class

Network IntroductionDefinition – Global network connecting million of computers exchanging data.History – Started in 1957 known ARPA within DoD, then being awarded

ARPANETRoadmap / New Technologies

IPv6 - Internet Protocol Version 6 is an evolutionary step from IPv4 featuring Large address space, Efficient and hierarchical addressing and routing infrastructure, Built-in security, Better support for quality of service (QoS)

Ultra Wideband (UWB) - MultiBand OFDM wireless using very high data rates and low power consumption radio signal

Very High Bit Rate DSL (VDSL) - Aggregation up to 32 Synchronous High Bit Rate DSL (SHDSL) providing 10Mbits/sec bidirectionally over copper

Internet & Network IntroductionIntroduction & Type

Roadmap / New Technologies (cont.)

Ethernet Virtual Connections (EVCs) - A standard for creating ATM-like PVCsacross Ethernet, will replace point-to-point circuits. Ethernet WANs will replace frame relay clouds with Virtual Private LAN Service (VPLS), a layer-2 VPN that will add security to EVCs to create LAN interconnect services

HighSpeed TCP – Reworking TCP to support higher / more efficient load


Internet & Network IntroductionHistory of USMNet

1994 – USMNet started

• FDDI technology (Fiber Distributed Data Exchange)• Retix Routers• 35 km fiber optic cable lay for 3 Campuses (Main, Kubang Kerian

& Tronoh)• All main buildings are connected with 1500 nodes.

– especially academician, administrative and general office• 64Kbps access to JARING for Main Campus• 9.6Kbps access to JARING for Kampus Cawangan Kelantan &

Kampus Cawangan Perak)


PPPBang&PerancangPkomputer

PPPengurusan

PPTek.IndPPSFizik

PPSKemasyarakatanPPIKemanusiaan G02

JX D18

C15

C22

F03 D37

PPIPendidikan

BCombits

PTMaklumatPPJJ

Pentadbiran

FalakHEP

PTPMPbahasaCPR

Perpustakaan

PPSKomputerPPSMatematik

PPSFarmasiJpembangunanPinovasiPPDadah

PPSKimiaPIslam PPSKajihayat

FDDI

FOIRL

Rx7000

Rx7000

Cent100

ONLine

ONLine

ONLine

Cisco

JARING

64Kbps

USMNet (Penang) - 1994


1998 – USMNet upgrade• 1.5Mbps access to JARING (started on 14 July 1998)• Numbers of nodes increase more than 3000:

– 99% academician, administrative & general office– Lab at school

• Locally connected from main campus to branch campus (Kelantan & Tronoh) through Celcom Microwave 256kbps.

• 9.6kbps access to jaring for branch campus was terminated.• No of users:

– Academic: 1,200– Administative: 500 – Student: 20,000


PPTekIndPPSFizik

PPSKemasy.PPIKem.

G02

JX D18

C15

C22

F03 D37

PkomputerPPPengurusan

PPIPendPPKomunikasi

PPPBang&Pembangunan

BCombits

PTMaklumatPPJJ

Pentadbiran

FalakHEP

PTPMPbahasaCPR

Perpustakaan

PPSKompPPSMath

PPSFarmasiJpembangunanPInovasiPPDadah

PPSKimiaPislam PPSKajihayat

FDDI

FOIRL

Rx7000

Rx7000

CB3500

ONLine

ONLine

ONLine

W/Fleet KCK

KCP

256Kbps

JARING1536Kbps

NetBuilder

USMNet - before 2000

256Kbps


2000 – USMNet Upgrading• FDDI was replaced with gigabit technology• 2x2Mbps access to JARING • 2Mbps access to JARING for Engineering Campus and Medical

Campus• Connection within campus (Main to Engineering/Medical) are

connected locally through 2x2Mbps (2002) • Data, Video and Voice in one network (2002)• Wireless technology implemented in Desasiswa

Internet & Network IntroductionHistory of USMNetUSMNet - 2003

Internet & Network IntroductionHistory of USMNetUSMNet - 2007

Internet & Network IntroductionHistory of USMNetCase Study – USMNet 2008

Internet & Network IntroductionComponents-Case Study

Case Study – USMnet Penang WIFI

Antenna /Access point

JARING

Pejabat Desasiswa

DESASISWA

USMNet

Type Of NetworkLAN (Local Area Network)

• Ethernet, Token Ring• Hub & Switches• UTP Cat. 5E & 6, Fiber Optic• Novell, Win NT,Win 2K, Win

XP,Win Vista, Unix, LinuxMAN (Metropolitan Area Network)

• Fiber Optic Cable• Routers & Switches• Network Admin

WAN (Wide Area Network)• PSTN, ISDN,Frame

Relay,ATM,Satellite• Routers & Switches• Internet


Network Topology

Bus Topology- A bus consists of a wire and shield

(coaxial), which electrically constitute a single circuit. At either end of a bus is a terminator, which is essentially a resistor and connected through a T Connector.

Client

ClientClient

Client Printer

PrinterClient

Internet & Network IntroductionTopology

Star Topology- This is a star configuration and it is

found in Ethernet networks that use twisted pair cable such as Cat 5, Cat 5E, Cat 6 and Fiber Optic.

- The twisted pair cable uses RJ-45 connectors that connect directly to the NIC on the device end, and to the hub on the other end while the Fiber use LX, FX, SC, ST Connectors to connect between network devices.

8 PortWorkgroup Hub

UTP Cat 5Cabling


Network Topology (cont.)

Ring Topology- A pure ring is a collection of separate point-to-point links, arranged to

make a ring which propagate a signals received on the input connection and passed immediately to the output connection by “repeater” circuitry in each node.

- The most common type of cabling used in ring topologies is fiber optic cable.

Client

Client Client

Client

DataFlow



Hybrid (Star Ring) Topology- The hybrid topology is a type of network topology that is composed of

one or more interconnections of two or more networks that are based upon different physical topologies



Networks ComponentsDevices

Terminal(Computers/Servers)Network Card / ModemNetwork CablingIncluding all UTP (Cat 5, Cat 5e, Cat 6, Cat 6a, Cat 7), Fiber Optics

Bridge (Broadcast & Collision Domain)A device that connects two local-area networks (LANs), or two segments of the same LAN that use the same protocol, such as Ethernet or Token-Ring.

Internet & Network IntroductionComponents - Devices

Devices (cont.)Hub/Switches (Broadcast & Collision Domain)A common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets. A switching hub or Switches, actually reads the destination address of each packet and then forwards the packet to the correct port.

Internet & Network IntroductionComponents - Devices

Internet & Network IntroductionComponents-Devices

RouterA device that forwards data packets along networks. A router is connected to at least two networks, commonly two LANs or WANsor a LAN and its ISP’s network

Devices (cont.)

HTTP-80

FTP-21

SMTP-25BackOrifice-31337


FirewallAccording to the National Computer Security Association, a firewall is “a system or combination of systems that enforces a boundary between two or more networks.” It is a controlled gateway between one network and another, typically between a private network and the Internet.

Devices (cont.)

Attack Detected !!

Internet

Reset


IDS (Intrusion Detection System)provide the inspection all inbound and outbound network activity and identifies suspicious patterns that may indicate a network or system attack from someone attempting to break into or compromise a system. An IDS evaluates a suspected intrusion once it has taken place and signals an alarm. An IDS also watches for attacks that originate from within a system.

Devices (cont.)

DirtyTraffic

CleanTraffic

WormsTrojansViruses

P2PSpyware

Intelligence Updates:Digital Vaccine®

NetworkPolicies

• Block Attacks• Throttle P2P Downloads• Block P2P Uploads


IPS (Intrusion Prevention System)device that monitors network and/or system activities for malicious or unwanted behavior and can react, in real-time, to block or prevent those activities. Will operate in-line to monitor all network traffic for malicious code or attacks. When an attack is detected, it can drop the offending packets while still allowing all other traffic to pass.

Devices (cont.)


UTM (Unified threat management)network firewalls that have many features in one box, including e-mailspam filtering, anti-virus capability, an (IDS or IPS), and World Wide Webcontent filtering , along with the traditional activities of a firewall.

Devices (cont.)


Traffic shaperWAN optimization/acceleration allows network pros to speed performance across the WAN with compression, caching, protocol shaping, and other techniques. It also lets network managers allot dedicated amounts of bandwidth to certain types of traffic to ensure that they are not competing

with other traffic for space in the pipe.

Devices (cont.)


AP (Access Point)A hardware device or a computer's software (NetBuddy) that acts as a communication hub for users of a wireless device to connect to a wired LAN.- Fat AP

In the autonomous architecture, the APs completely implement and terminate the 802.11 function so that frames on the wired LAN are 802.3 frames. Each AP can be independently managed as a separate network entity on the network.

- Thin APThe centralized architecture is a hierarchical architecture that involvesa WLAN controller that is responsible for configuration, control, and management of several APs. The WLAN controller is also known as the Access Controller (AC). The 802.11 function is split between the AP and the AC.

- Fit AP

Devices (cont.)


WiSM (Wireless Services Module)unparalleled security, mobility, redundancy, and ease of use for business-critical wireless LANs (WLANs). It allows network managers and operators to control and manage their wireless networks easily.

Devices (cont.)

ServersDNS (Domain Name System or Service)A Server that translates domain names into IP addresses.- Internal DNS- External DNS For example,

the domain name www.usm.mymight translate to 10.202.1.4 - internal DNS

202.170.56.73 - external DNS- DNS server USM 10.202.1.6/10.202.1.27

202.170.56.75/202.170.56.155

Internet & Network IntroductionComponents-Servers

Servers (cont.)DHCP (Dynamic Host Configuration Protocol )A server that provide an assigning dynamic IP addresses to devices on a network. With dynamic addressing a device can have a different IP address every time it connects to the network.

Proxy vs NAT (Network Address Translation) / MasqueradeA server that sits between a client application, such as a Web browser, and a real server. It intercepts all requests to the real server to see if it can fulfill the requests itself. If not, it forwards the request to the real server. (Http, Https, Ftp)


nat static nat dynamic nat overload

WINS (Windows Internet Naming Service )A server that provide a distributed database that is automatically updated with the names of computers currently available and the IP address assigned to each one.

DDNS (Dynamic DNS)dynamic Domain Name System, a method of keeping a domain name linked to a changing IP address as not all computers use static IP addresses. A dynamic DNS service provider uses a special program that runs on the user's computer, contacting the DNS service each time the IP address provided by the ISP changes and subsequently updating the DNS database to reflect the change in IP address.


Servers (cont.)

Web Cache / Content EngineOn the Internet, content delivery (sometimes called content distribution, content distribution delivery, or content caching) is the a server or appliance that provide a service of copying the pages of a Web site to geographically dispersed servers and, when a page is requested, dynamically identifying and serving page content from the closest server to the user, enabling faster delivery.

AAA (Authentication, Authorization & Accounting) – IEEE 802.1xA system in IP-based networking to control what computer resources users have access to and to keep track of the activity of users over a network.


Servers (cont.)


RadiusShort for Remote Authentication Dial-In User Service, a server that provide an authentication and accounting system used by many Internet Service Providers (ISPs). When you dial in to the ISP you must enter your username and password. This information is passed to a RADIUS server, which checks that the information is correct, and then authorizes access to the ISP system.

LDAP / NTLMShort for Lightweight Directory Access Protocol, a server that provide a set of protocols for accessing information directories.LDAP supports TCP/IP, which is necessary for any type of Internet access. Although not yet widely implemented, LDAP should eventually make it possible for almost any application running on virtually any computer platform to obtain directory information, such as email addresses and public keys. Because LDAP is an open protocol, applications need not worry about the type of server hosting the directory.

Servers (cont.)


PKIShort for public key infrastructure, a server that provide a system of digital certificates, Certificate Authorities, and other registration authorities that verify and authenticate the validity of each party involved in an Internettransaction. PKIs are currently evolving and there is no single PKI nor even a single agreed-upon standard for setting up a PKI. However, nearly everyone agrees that reliable PKIs are necessary before electronic commerce can become widespread. A PKI is also called a trust hierarchy.

Servers (cont.)

Internet & Network IntroductionComponents-Software

SoftwareServers Software

- Web (Apache, IIS) - Proxy/Web Cache (Squid, WinGate)- Email (Sendmail, Qmail, Lotus Notes)- DHCP (dhcpd)- DNS (Bind)- Firewall (IPtables)- Traffic Utilization (MRTG, Cacti)

NOS – Network Operating System- Cisco IOS- 3Com Network Agent

NMS (Network Management System)- 3Com Network Supervisor- HP OpenView- Ciscoworks LMS- Cisco Network Analysis Module- Tivoli- Websense- Fluke Agent

How Network OperateOpen System Interconnection (OSI) Architecture- Physical layer- Data Link Layer- Network Layer- Transport Layer- Session Layer- Presentation Layer- Application Layer

Internet & Network IntroductionInteroperation-OSI

How Network Operate

IP AddressIP Address (Local & Public)IP specifies the format of packets, also called datagrams, and the addressing scheme. Most networks combine IP with a higher-level protocolcalled Transmission Control Protocol (TCP), which establishes a virtual connection between a destination and a source.The current version of IP is IPv4. A new version, Called IPv6.

IP Address ExamplesVersion 4 – Public : 202.170.56.73 / 255.255.255.255

Local : 10.202.1.4 / 255.255.255.255Version 6 – Public : 2001:328:400:2::22


VLSM / CIDR

- Variable-Length Subnet Mask - allocating IP addressing resources to subnets according to their individual need rather than some general network-wide rule.Used in the IP routing protocols supported by OSPF, Dual IS-IS, BGP-4, and EIGRP support "classless" or VLSM routes.

- Classless Inter-Domain Routing, an IP addressing scheme that replaces the older system based on classes A, B, and C. With CIDR, a single IP address can be used to designate many unique IP addresses. A CIDR IP address looks like a normal IP address except that it ends with a slash followed by a number, called the IP network prefix


Port Number (2-16 )- The port numbers are divided into three ranges: the Well

Known Ports, the Registered Ports, and the Dynamic and/orPrivate Ports.

- The Well Known Ports are those from 0 through 1023 (system services)

- The Registered Ports are those from 1024 through 49151- The Dynamic and/or Private Ports are those from 49152 through

65535

VLAN (Virtual Lan)Virtual LAN, group of devices on one or more LAN that are configured (using management software) so that they can communicate as if they were attach to the same wire, when in facts they are located on a number of different LAN segments.


Internet & Network IntroductionTroubleshooting-Tips

Network TechnologiesWired NetworkWireless Network

802.11b- Enhancement to 802.11 that added higher data rate modes to the DSSS

(Direct Sequence Spread Spectrum) already defined in the original 802.11 standard

- Boosted data speed to 11 Mbps- 22 MHz Bandwidth yields 3 non-overlaping channels in the frequency

range of 2.400 GHz to 2.4835 GHz- Beacons at 1 Mbps, falls back to 5.5, 2, or 1 Mbps from 11 Mbps max 802.11a- Specifies a PHY that operates in the 5 GHz U-NII band in the US - initially

5.15-5.35 AND 5.725-5.85 - since expanded to additional frequencies- Uses Orthogonal Frequency-Division Multiplexing- Enhanced data speed to 54 Mbps - Ratified after 802.11b

Internet & Network IntroductionTroubleshooting-TipsNetwork Technologies

Wireless Network (cont.)802.11g- Extends the maximum data rate of WLAN devices that operate in the 2.4 GHz band, in a fashion that permits interoperation with 802.11b devices

- Uses OFDM Modulation (Orthogonal FDM)- Operates at up to 54 megabits per second (Mbps)802.11n - Multiple-In, Multiple-Out (MIMO), a radio technique that increases the

range of Wi-Fi networks by sending transmissions via multiple antennas. Dubbed the Intelligent RF Access Point (IRAP)

- Airespace claims it will increase the range of 802.11 networks beyond their usual 100-meter limit, as well as help eliminate dead zones, areas within range of a Wi-Fi AP where reception is poor or non-existent due to obstacles that block radio propagation.

- Operates at up to 248 megabits per second (Mbps)Fat AP, thin AP, Light AP, MIMO, Mesh Broadband Wireless - WiMax

Type Of NetworkLANMANWAN

ServicesISPs (Internet Services Provider)- Jaring, Tmnet, Time, MaxisTelco (Telecommunication Company)- Telekom, Teleglobe, MaxisNetwork Admin - (NOC – Network Operating Center)

Internet & Network IntroductionInteroperation–Type & Services

Understand The InternetDefinition

- Global Community

Protocol as standard communication- TCP/IP (Transmission Control

Protocol / Internet Protocol)

Connection Medium- UTP (Cat 5E, Cat 6)- Leased Line (E1, T1)- Satellite - KU-Band (C-Band:SCPC, DAMA, FDMA)- Broadband (ISDN, DSL)- Modem (V.90) (PPP / SLIP)

Internet & Network IntroductionInteroperation–Internet & Medium

USMNetLAN

PBX

FirewallFirewall

Router

S a te lliteSatellite

Leased line

Internet Cloud

Computer

Home User

Modem/DSL

DAMA/FDMA

Multiplexer

UTP Cat6

UTP Cat6

UTP Cat6

VConf

Where are u in the picture?

Function Explanation- Networking concept through OSI 7 Layers only happen when data

travel from source to destination.- Data from any sources will be transferred to the destination through mutual

handshaking.- OSI 7 Layers manipulate and ensured that the data are safely transferred.- All the network devices such as switches, routers, firewall etc involve

to ensure the data transmission.- During the transmission, data will be monitored ,checked and rectified

through checksum mechanism to ensure the validity and integrity.

Internet & Network IntroductionInteroperation–Function Explanation

Network Application & FacilitiesApplication Method

– Freeware– Shareware– Paid

Application Category- Database (SQL, Oracle, Sybase)- Monitoring Tools (Tivoli, NMS, NMap)- File Transfer (FTP, Gopher, WAIS)- Instant Messaging / Chat (IRC, ICQ, YM, Jabber)- Mail And Collaboration Tools (SMTP, IMAP, POP3, Lotus Notes)- Network OS (Telnet, FTP, SSH, NTP, LDAP, Finger, NFS, ident, daytime)- P2P File Sharing (Kazaa, Imesh, Gnutella, Skype)- Remote Access (pcAnywhere, VNC, Terminal Service, Citrix)- Streaming Media (Liquid Audio, RTSP, Windows Media)- Web (HTTP, HTTPS)- E-Learning – Lotus Notes- Others (NNTP, Internet Telephony, Video Conferencing, Personnel Network

Storage, Spyware, Adware)

Internet & Network IntroductionApplication & Facilities

Network Threats & Securities

Network security specialists classify thesethreats as follows:

HackersWhereas crackers sole aim is to break into secure systems, hackers are more interested in gaining knowledge about computer systems and possibly using this knowledge for playful pranks. Although hackers still argue that there's a big difference between what they do and what crackers do, the mass media has failed to understand the distinction, so the two terms –hack and crack -- are often used interchangeably.

Trojan horsesA destructive program that masquerades as a benign application. Unlike viruses, Trojan horses do not replicate themselves but they can be just as destructive. One of the most insidious types of Trojan horse is a program that claims to rid your computer of viruses but instead introduces viruses onto your computer.

Internet & Network IntroductionThreats & Securities

Internet & Network Introduction

Viruses

Fast, systematic, and self-replicating destructive programs designed to

damage systems and networks by eroding executable programs until they

are unusable

WormsA program or algorithm that replicates itself over a computer network and usually performs malicious actions, such as using up the computer's resources and possibly shutting the system down.

Spam Electronic junk mail or junk newsgroup postings. Some people define spam even more generally as any unsolicited e-mail. Real spam is generally e-mail advertising for some product sent to a mailing list or newsgroup. In addition to wasting people's time with unwanted e-mail, spam also eats up a lot of network bandwidth. However, some online services have instituted policies to prevent spammers from spamming their subscribers.

Threats & Securities

Internet & Network IntroductionThreats & Securities

Spyware Also called adware, spyware is any software that covertly gathers user information through the user's Internet connection without his or her knowledge, usually for advertising purposes. Spyware applications are typically bundled as a hidden component of freeware or sharewareprograms that can be downloaded from the Internet. Once installed, the spyware monitors user activity on the Internet and transmits that information in the background to someone else. Spyware can also gather information about e-mail addresses and even passwords and credit card numbers.

Banditsinsiders seeking unauthorized information for personal gain

Internet & Network IntroductionThreats & Securities-Protection

For protection against these risks, network and system managers tasked with security responsibilities evaluate and examine alternatives, which are based on hardware and software, or policies

Endpoint Security SuiteAccess Control ListNetwork Monitoring & Filtering Software & Tools

- Firewall- IDS / IDP- Proxy- Websense- LDAP / NTLM- PKI- AAA

Internet & Network IntroductionTroubleshooting

Network Troubleshooting

Every user are encourage to learn and now day become compulsory to gainknowledge to identify simple or common network problem due to highdependency on it in daily communication/task. Thumb rule in anytroubleshooting, check the physical connection at first.

Common Problems.Can’t surf internet.Can’t read E-mail.Can’t find other computer/server.(usmadmin)Can’t connect to Lotus Notes server.Can’t see other computer through network neighborhood.Can’t use local application (e-cuti).Can’t access outside server.(ftp,telnet,ssh)Personnel server can’t serve appropriately.

Where to

start?

Internet & Network IntroductionTroubleshooting-Compulsory Steps

Compulsory Steps :Steps 1: Check the Modem status. (Dial-up & DSL)

- Check the phone line connection. - Check the modem driver & configuration.- Check the dial application configuration.- Capture the error message and ask the ISP.

Steps 2: Check the NIC signals, whether there is a light/color/blinking. This is to ensure the NIC is function and some NIC product shows the speed of connection. If not

- Check the cable connection from your Network/Ethernet adapter tothe wall jack

- Check the NIC driver - Verify and/or reinstall your network Ethernet and TCP/IP settings- Reboot your pc.- Change NIC if above steps taken and NIC still don’t blink.

* Some product provide diagnose tool. Use it to troubleshoot the problem.


Steps 3: Check the IP Address.- Use: winipcfg, ipconfig, ifconfig. Rectifying the IP, Gateway and Name

Server.- Identify either static ip / dynamic ip used at TCP/IP settings.- Use ping, tracert, nslookup, dig tools. - Capture the error message and ask Network Admin if dynamic IP could

not be retrieve after above steps taken.- Make sure virus free

Common Problems Solution:For Internet browsing problem

- Follow the Compulsory Steps.- Identify the IP type either Public or Local.- For local IP should use proxy server. Test the Proxy server

availability and proxy configuration.- Capture the error message and ask the Network Administrator.

Troubleshooting-Problem Solution


For E-mail problem- Follow the Compulsory Steps.- Test the e-mail server availability.- Understand the e-mail client type (IMAP, POP3, HTTP) and rectify the

e-mail client configuration.- Capture the error message and ask the Server & Network Administrator.

Can’t find other computer/server (Lotus Notes/usmadmin)- Follow the Compulsory Steps.- Make sure target computer/ server are up/active.- Rectify the searching method. Test the server availability.- Capture the error message and ask the Server Administrator.

Can’t use local application (e-cuti).- Follow the Compulsory Steps.- Make sure target computer/ server are up/active.- Rectify the application configuration at client site.- Capture the error message and ask the Application Administrator.

Troubleshooting-Problem Solution


Can’t access outside server.(ftp,telnet,ssh)- Follow the Compulsory Steps.- Make sure the IP Address used is the public one (P2P connection)

Personnel server can’t serve appropriately (Personnel Web-Server)- Follow the Compulsory Steps.- Make sure all the necessary steps needs by server have been taken.- Capture the error message and ask the Network Administrator.

Some tools / technique could be use which is available in every OS:PingPing is used to test network connectivity respond between two computers on a network using ICMP protocol.Eg: ping your.ip.address

ping your.ip.gatewayping your.ip/name.target

Ipconfig/Ifconfig

Troubleshooting-Tools & Technique


TracerouteTraceroute is use to test a lag in a communication or the point of network failure on a network (intranet / internet) resulting poor or no communication which is testing every network routing known as Hop.Eg: tracert jaring.com.my

NslookupNslookup can be use in situation where a computer can ping an IP Addressbut not the computer name. This is to determine whether the DNS servercan resolve the alias of the IP Address Eg: nslookup jaring.com.my

NetstatNetstat is use to show all the open port, protocols statistics and currentTCP/IP connection at the user terminal.Eg: netstat –a


Troubleshooting TipsMake sure virus free.Understand network related facilities used (IP Address, network servers, network structure, application dependencies)Check the physical connection at first.Understand the problem. Capture the error message.Ask the Network Administrator if problem un-solve after appropriate action has been taken.

Q & A Session

Perkongsian Maklumat Rangkaian USMNetBahagian Infostruktur

Thanks

Perkongsian Maklumat

Technology

Transcript of Perkongsian Maklumat