Tài liệu học CCNA kỳ 1 mod5 CablingLANWAN

Module 5- Cabling LANs and WANsNIIT-ICT Hanoi info@niithanoi.vn Contents • Characteristics of Ethernet networks • Identify cables, hub, switch, bridge, wireless LAN • Peer-to-peer and cl

Trang 1

Module 5- Cabling LANs and WANs

NIIT-ICT Hanoi info@niithanoi.vn

Contents

• Characteristics of Ethernet networks

• Identify cables, hub, switch, bridge, wireless LAN

• Peer-to-peer and client-server networks

• WAN equipment , ISDN, DSL, cable modem

Trang 2

Ethernet: LAN physical layer

Ethernet in the campus

• Ethernet was first implemented by the Digital,

Intel, and Xerox group, referred to as DIX

• Institute of Electrical and Electronics Engineers

(IEEE) 802.3 specification

• The IEEE extended 802.3 to three new

committees known as 802.3u (Fast Ethernet),

802.3z (Gigabit Ethernet over Fiber), and 802.3ab

(Gigabit Ethernet over UTP)

Trang 3

Ethernet in various usage

• An Ethernet speed of 10 Mbps can be used at the user

level to provide good performance Clients or servers that

require more bandwidth can use 100-Mbps Ethernet

• Fast Ethernet is used as the link between user and

network devices It can support the combination of all

traffic from each Ethernet segment

• To enhance client-server performance across the campus

network and avoid bottlenecks, Fast Ethernet can be used

to connect enterprise servers

• Fast Ethernet or Gigabit Ethernet , as affordable, should

be implemented between backbone devices

Ethernet media and connector requirements

• Ethernet implementations are derived from the

Electronic Industries Association and the

Telecommunications Industry Association

(EIA/TIA)

• The categories of cabling defined for Ethernet are

derived from the EIA/TIA-568

Trang 4

Trang 5

The RJ45 plug and its cabling in side

The RJ45 Jack and its pins

Trang 6

straight-through cable

crossover cable

Cable usages:

X connects to X by crossover

None X connects to none

X by crossover None X connects to X by straight

Trang 7

A repeater receives a signal, regeneratesit, and passesit on

It can regenerate and retimenetwork signals at the bit level to allow them to

travel a longer distance on the media

The Four Repeater Rule for 10-Mbps Ethernet should be used as a standard

when extending LAN segments

5-4-3-2-1rule states that no more than four repeaters can be used between

hosts on a LAN

Repeater

•Multi-port repeaters

•Most commonly used in Ethernet 10BASE-T or 100BASE-T networks

•There arePassive, Active, Intelligenthubs

•The more devices there are attached to the hub, the more likely there will be

collisions Every device connected to the same network segment is said to

be a member of a collision domain

Hub

Trang 8

Passive– A passive hub serves as a physical connection point only It does not

manipulate or view the traffic that crosses it It does not boost or clean the signal, so

the passive hub does not need electrical power

Active– An active hub must be plugged into an electrical outlet because it needs

power to amplify the incoming signal before passing it out to the other ports

Intelligent– These devices basically function as active hubs, but also include a

microprocessor chip and diagnostic capabilities

Hub

•Wireless signals are electromagnetic waves that travel through the air

•Wireless networks use Radio Frequency (RF), laser, infrared (IR), or

satellite/microwaves to carry signals

•The two most common wireless technologies used for networking are IR and RF

•Two approaches currently being used to implement spread spectrum for WLAN

transmissions are Frequency Hopping Spread Spectrum (FHSS) and Direct

Sequence Spread Spectrum (DSSS)

Wireless

Trang 9

• Break up a large LAN into smaller, more easily managed segments, decreases

the amount of traffic on a single LAN ( switches, routers, and gateways also can

do)

1 Destination is samesegment = don’t forward

2 Destination is on differentsegment = forward

3 Destination is unknown= forward to all segmentexcept the onethat received it

Bridge

• Multi-port bridge

• Similarity to bridge but a switch choosesthe port to which the destination device or workstation is connected

• Switch : improve network performance by improving speed and bandwidth, alleviates congestion, replacing hubs with existing cable infrastructures

Switch

Trang 10

Switch functions & benefits

• Switching data frames is the process by which a frame is received on an input medium and then transmitted to an output medium Maintenance

of switching operations

where switches build and maintain switching tables and search for loops

• operate at much higher speeds than bridges and can support new functionality, such as virtual LANs

• parallel in communication:

use of virtual circuits (in a virtually collision-free environment )

• To connect a host device to the network medium

• NICs are considered Layer 2 devicesbecause each NIC carries a unique

code called a MACaddress

• Consideration: expansion slot, network media/connector (may included

transceiver)

NIC, Host connectivity

Trang 11

• Networked computers take on different roles or functions in relation to each other

• Individual users control their own resourcesusers may decide to share certain files with other users, no central point of control or administration in the network

• Relatively easy to install and operate

• Doesn’t scale up well (less than 10 computers)

Peer-to-peer Network

• Network services are located on a dedicated computercalled a server

• Before a client can access the server resources, the client must be identified and be authorizedto use the resource

• Concentration of network resourcessuch as files, printers, and applications

on servers also makes the data generated easier to back-up and maintain

Client/server Network

Trang 12

CSU/DSU

Modem

Telco Service Provider (Cloud of WAN Switches)

CO Last Mile

or Local Loop

Local LAN

Remote

User

Router

CPE

RAS

WAN Connections

• CO : Central Office.

• Local loop or “last mile”.

• CSU : Channel Service Unit.

• DSU : Data Service Unit.

• Demarc : Demarcation Point.

• CPE: Customer Premises Equipments.

• Router.

• Modem.

• Local LAN.

• DTE: Data Terminal Equipment.

• DCE: Data Communication Equipment.

• Remote User.

• RAS: Remote Access Server.

• WAN Switch.

• WAN Link.

External CSU/DSU

• For digital lines, a channel service unit (CSU)and a data service

unit (DSU)are required

– We won’t go into the differences here

• The two are often combined into a single piece of equipment, called

the CSU/DSU

To router

To T1 circuit

Trang 13

WAN physical layer

T1/E1 or above

Up to T1/E1 ISDN (BRI): two 64

kbps (B channels) for data, one (D channel)

at 16 kbps

2400bps up to

T1(1.544M),

E1(2.048M)

WAN serial connections

• WANs use serial transmission

• Normally the router will be

a data terminal equipment (DTE) and use a DTE serial cable A device that provides signal clocking such as a channel/data service unit (CSU/DSU) will connect to it

Trang 14

Router & serial connections

• Router connects WANs and LANs

• Router serial cable is DTE but maybe DCE if need to configure back-to-back

• Interfaces on routers with fixed serial portsare labeled for port type and port number, e.g S0, S1, E0, F0

• Interfaces on routers with modular serial portsare labeled for port type, slot, and port number, e.g

s0/1, fa0/0

Router and other connections

ISDN BRI interface

Cable TV interface

DSL interface

Trang 15

Router & console connection

• The console portallows monitoring and configuration of a Cisco hub, switch,

or router

• Need rollover cableand configure the terminal emulation applicationwith the

following common equipment (COM) port settings: 9600 bps, 8 data bits, no

parity, 1 stop bit, and no flow control

• The AUX portis used to provide out-of-band management through a modem

Summary

• A network interface card (NIC)

• Use a crossover cable to connect between two similar devices,

such as switches, routers, PCs, and hubs

• Use a straight-through cable to connect between different

devices, such as connections between a switch and a router, a

switch and a PC, or a hub and a router

• There are two major types of LANs, peer-to-peer and

client/server

• WANs use serial data transmission WAN connection types

include ISDN, DSL, and cable modems

• A router is usually the DTE and needs a serial cable to connect

to a DCE device like a CSU/DSU

Trang 16

Summary

• The ISDN BRI has two types of interfaces, S/T and U interfaces

To interconnect the ISDN BRI port to the service-provider

device, a UTP Category 5 straight-through cable with RJ-45

connectors, is used

• A phone cable and an RJ-11 connector are used to connect a

router for DSL service

• Coaxial cable and a BNC connector are used to connect a

router for cable service

• Rollover cable is used to connect a terminal and the console

port of an internetworking device

Lab

• Establishing a Console Connection to a Router

or Switch

• Identify router interface names

• Setup simple WAN with two PCs, two switches,

two routers

Trang 17

• http://www.erg.abdn.ac.uk/users/gorry/course/ phy-pages/

phy.html

• http://www.kan.org/networking/ nethardware.html

• http://searchnetworking.techtarget.com/

sDefinition/0,,sid7_ gci213079,00.html

• http://searchsystemsmanagement.techtarget.com/

sDefinition/0,,sid20 _gci212660,00.html

• http://www.vtac.org/Tech/TDbasics_of_ switching.htm

• http://www.webwisdom.com/edu_content/ cps640fall00/

lectures/module3/WAN/ sld008.htm

Định dạng
Số trang	17
Dung lượng	551,61 KB