Cabling LAN and WAN

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Cabling LAN and WAN

• Cabling the LANwhen to use Ethernet, Fast
  Ethernet,Gigaethernet?
• LAN devices
• Collision Domain
• Cabling the WAN Serial Cables
• WAN devices
• Peer to Peer or Client Server Networks

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LAN physical layer
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Ethernet in the campus
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Ethernet

• Ethernet is the most widely used LAN technology
• Ethernet technologies can be used in a campus
  network in 3 ways
• user level-- An Ethernet speed of 10 Mbps.
• Fast Ethernet -- link between user and network
  devices (PC to switch). Also between PC and
  server.
• Fast Ethernet or Gigabit Ethernet -used between
  backbone devices.

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Ethernetmedia
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LAN Connection
RJ-45 Connector
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Repeaters Layer 1 device

• repeaters regenerate a signal and pass it on.
• It also regenerate and retime network signals at
  the bit level to ( travel a longer distance on
  the media)

• The 10-Mbps Ethernet has the Four Repeater Rule
• no more than 4 repeaters can be used between
  hosts on a LAN
• used to limit delay or latency
• Too much latency on the LAN increases the number
  of collisions

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Hub (Layer 1)

• Hub Multi-port repeater
• a repeater 2 ports, a HUB has from 4 to 24
  ports
• hubs are also called concentrators
• Hubs come in three basic types
• Passive A physical connection point only no
  electrical power.
• Active needs power to amplify the incoming
  signal before passing it out to the
  other ports

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Hub
Collision domain

• Hub is a physical ________ and logically a bus.
• more devices connected hub, the more likely for
  collisions.
• A collision occurs when two or more workstations
  send data over the network wire at the same time.
  
• All data is corrupted when that occurs.
• Every device connected to the same network
  segment is said to be a member of a collision
  domain. (a collision area)

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Bridge L2 Device
Collision domain

• Too many PCs ? too many collisions ?break up a
  large LAN into smaller collision domain How?
• use Bridge, router or switch
• bridges operate at the Data Link layer (L2) of
  the OSI model.
• Bridge is like a traffic light that allows or
  stops (traffic) a frame.
• A bridge/switch therefore has two main functions
• switch data frames
• build and maintain tables

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Bridge
Switching Table
use F5-2D
A bridge/switch forwards or blocks a frame using
destination MAC address. Three
states- Filtering (blocking) If A sends frame
to C bridge blocks and frame wont go on
segment2 Forwarding If A sends frame to E
bridge forwards it to segment 2. Flooding
bridge gets frame with unknown MAC address
bridge forwards
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Switches

• A bridge only has 2 ports 2 segments
• A switch is a multi-port bridge
• Each port has one segment is a collision domain
  (with only 1PC)

• All switches perform two basic operations.
• Switching data frames
• Building and maintaining switching tables

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Wireless

• A wireless network
• less cabling than other networks.
• use Radio Frequency (RF), laser, infrared (IR),
  or satellite/microwaves
• Provides data communication is for mobile user

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Host connectivity

• The function of a NIC is to connect a host device
  to the network medium
• The NIC is also referred to as a network adapter

NICs are considered Layer 2 devices because each
NIC carries a unique code called a MAC (physical)
address.
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WAN physical layer
Link Type Connector

• WANs use serial transmission (one by one and not
  parallel).
• This is a process by which bits of data are sent
  over a single channel

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WAN configurations

• WAN through telephone wire, cable, Modems,
  Routers
• Serial connections are used to support WAN
  services

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Routers and serial connections
Serial Interface
Console
Router has both LAN and WAN ports LAN Ethernet
10Base T WAN Serial interface Admin Console
interface
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WAN DTE/DCE

• Router connects to service provider (ISP),
• Modem is DCE or CSU/DSU,
• Router is DTE (data terminal equipment) and use
  a DTE serial cable.
• The (DCE) CSU/DSU provides the clock signal.

Clock
Clock
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Cabling LAN/WAN

• Identify the cables.

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Straight or Cross-Over

• crossover cable --such as switches to switch
• routers to router PC to PC, and hub to hub.
• Use a straight-through cable to connect between
  different devices, such as
• a switch to a router,
• a switch to a PC,
• a hub to a router.
• Routers RJ45 pinout PCs

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Setting up console connections
To config or program Switch/router

• The console port allows configuration (enter IP
  addresses) of Cisco switches or routers
• The cable used between a terminal and a console
  port is a rollover cable also known as a console
  cable

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Peer to peer network

• In a peer-to-peer network
• networked computers act as equal partners, or
  peers
• individual users control their own resources
• Peer-to-peer networks are relatively easy to
  install and operate

• A peer-to-peer network
• works well with 10 or fewer computers
• do not scale well, their efficiency decreases
  rapidly as the number of computers on the network
  increases
• Security is difficult to maintain

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Client/Server

• In a client/server network services are located
  on a server
• The server is a central computer that is always
  available to answer requests from clients for
  file, print, and application services
• Servers are designed to handle requests from many
  clients simultaneously
• The centralization of resources on server systems
  brings greater security, simpler access and
  coordinated control,
• Disadvantage the server introduces a single
  point of failure

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Peer-to-Peer vs. Client/ServerAdvantages/Disavant
ages