Semester 2 v3'1'1: Routers and Routing Basics

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Semester 2 v3.1.1Routers and Routing Basics

• MODULE 1
• WANs and Routers

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WAN? Never heard of it

• Provides long-distance connections at a lower
  data rate between networking devices across a
  large geographical area.
• ... unlike LANs, which generally connect end-user
  devices (eg. workstations, printers) across a
  small area (eg. a building).
• Usually long-distance links owned and operated by
  telcos, and leased out to customers.
• American WAN providers include Regional Bell
  Operating Companies (RBOCs), ATT (formerly SBC
  and BellSouth), Sprint, Verizon, Qwest, and MCI
  (formerly WorldCom).
• Australian WAN providers include Telstra, SingTel
  Optus, Macquarie Telecom, Soul, AAPT, PowerTel,
  and TransACT.
• The Internet is a collection of WANs.

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More on WANs

• Devices in a WAN include
• Routers
• Modems (including CSU/DSUs and TA/NT1s)
• Communications servers
• WAN physical layer describes the connection
  between DTE and DCE, implemented by standards
  such as E1, E3, xDSL, and SONET.
• WAN data link layer protocols include HDLC, PPP,
  Frame Relay, ISDN, ATM, SLIP, and SDLC.

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Router? Dont know that too

• Routers use routing tables to determine the most
  efficient path for packets to take to their
  destination.
• Determines next hop for incoming packets to take
  based on directly connected subnets or routing
  protocols
• WAN technologies are frequently used to connect
  routers.
• A major role for routers in WANs is to provide
  connections between subnets and various WAN links

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Whats in the box?

• RAM (Random Access Memory)
• Stores routing tables and ARP cache.
• Run time space for Cisco IOS (Internetwork
  Operating System) to load and execute, and for
  temporary router configuration files to be
  stored.
• NVRAM (Non-Volatile RAM)
• Stores router initialisation configuration files.
• Unlike RAM, NVRAM doesnt lose contents when
  powered down.
• Flash Memory
• Stores Cisco IOS software images, allows for
  software upgrades on the fly.
• Retains contents when powered down.
• ROM (Read Only Memory)
• Stores the hardware diagnostics code that runs
  upon startup.

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Get plugged in to routers

• Management asynchronous serial lines are
  primarily used for router configuration purposes.
• LAN and WAN interfaces connect routers to
  networks to accept and redirect packets.

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How to console a router

• Use management ports to configure a router
• Console ports require a rollover cable to connect
  to the serial port of a host running terminal
  emulation software, eg. HyperTerm
• AUX ports are connected to a modem used for other
  hosts to dial-in to, to establish a remote
  connection.

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Routers in LANs and WANs

• LAN Interfaces
• Usually Fast Ethernet over Cat5 (or higher grade)
  UTP.
• Can also be Token Ring, or Gigabit Ethernet over
  fibre.
• WAN Interfaces
• Serial and ISDN technologies across leased line,
  circuit-switched, and packet-switched
  connections.
• A variety of physical connectors are used for WAN
  links.
• Most common is serial link between DTE and DCE
  devices.

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Welcome to my world )

• Daniel Comarmond
• CCNP, CCDP, CCSP, CCAI
• Cisco Networking Academy Instructor
• Systems Engineer Cisco Systems
• E-Mail dcom_at_it.uts.edu.au
• MSN dcom82_at_dcom82.com
• Phone [phone]
• Website http//www-staff.it.uts.edu.au/dcom
• Take care, and SMILE!!! )