CISCO NETWORKING ACADEMY Chabot College ELEC 99.08 Router Introduction.

CISCO NETWORKING ACADEMYCISCO NETWORKING ACADEMY

Chabot CollegeChabot College

ELEC 99.08ELEC 99.08Router Introduction


What is a Router?What is a Router?

• A special purpose computer

• Hardware and software dedicated to path selection and packet switching

• Cisco routers derived from Unix computers


PC vs. RouterPC vs. Router

• Temporary Storage (volatile)

RAM RAM

RAM - Random Access MemoryDRAM - Dynamic Random Access MemoryContents are lost when router is powered off.



• Long-Term Storage (non-volatile)

Hard Disk NVRAM

Non Volatile RAMContents are saved when router is powered off.



• Serial Communications

Serial Interfaces(COM1,COM2)

Serial Interfaces(S0, S1)

Used for printers, modems Used for WAN



• LAN Communications

Ethernet NICEthernet Interfaces

(E0, E1)



• Boot Instruction Sequence

ROM ROM



• Operating System

Windows IOS

Internet Operating System



• Flash memory function

Stores BIOS Stores IOS



• User interaction

MonitorKeyboard

Mouse

Terminal

(connects to console port via “rollover” cable)


What is a Terminal?What is a Terminal?

• User box– Monitor– Keyboard– Serial port (connects to host)

SD

SERIAL 0 SERIAL 1 CONSOLE AUX

CISCO 2514

Input: 100-240VACFreq: 50.60 HzCurrent: 1.2-0.6AWatts: 40W

AUIAUI

• Has no:– CPU– Storage– Operating system


What is a “rollover” cable?What is a “rollover” cable?

• Straight-through cable with connections at one end completely reversed. (Turn the rj-45 plug upside down on one end.)

• Connects to Cisco router console port.


Router Port SummaryRouter Port Summary

• Serial Interfaces– WAN links– Names: S0, S1– V.35 Cable

• Ethernet Interfaces– LAN links– Names: E0, E1– Transceiver / Twisted-pair cable



• Console Port– Terminal connection to configure router– Name: con0– Rollover cable

• Aux Port– Modem connection to configure router– Name: aux0– Rollover cable



• Virtual Terminal ports– Virtual, not physical ports– Users reach these ports via Telnet– Names: vty0, vty1, vty2, vty3, vty4


Router CapabilitiesRouter Capabilities

• Main Functions– Path selection– Packet switching

• Additional Functions– Broadcast containment– VLAN links– Security / Access control


Router RolesRouter Roles

• Network Edge– WAN links to other sites in the enterprise– WAN gateway to Internet

• Network Core– Backbone links– Collapsed backbone

• Anywhere– Network segmentation device– Security device



• WAN links to other sites in the enterprise– Example: connect Chabot to Las Positas– Use serial ports– Low bandwidth, compared to LAN (T-1 is

1.54 mbs)– Cisco 2500 series router used frequently for

this role.



• WAN Gateway to Internet– Example: connects CLPCCD network to ISP– Uses serial port– Low bandwidth, compared to LAN (T-1 is

1.54 mbs)– Cisco 2500 series router used frequently for

this role



• Backbone links– Connect user groups to backbone– Use ethernet ports (or other LAN ports such as

token ring or FDDI)– High bandwidth, (Typically 10 or 100 mbs)– An older network design– Cisco modular routers used frequently for this

role (e.g. 3600, 4000 series), but can be done with 2514 in low traffic situations



• “Collapsed Backbone”– Backbone in a box; center of extended star– Uses ethernet ports or fast ethernet ports– A modern network design– Uses high-end Cisco routers (e.g.7500 series)– Router often works with large switches to

manage VLANS.



• Network segmentation device– Router links:

• networks• subnets• switch VLANS

– Broadcasts (usually) not forwarded– Router works together with high-end switch

(ISL) or router module is part of the switch



• Security device– Access control rules allow router to control

traffic between:• networks• subnets• switch VLANS

– Traffic regulated by “Access Control Lists”



• The Cisco 7507 at the core of Chabot’s net performs all these roles:– WAN links to other sites in the enterprise– Collapsed backbone– Network segmentation device (VLAN links,

broadcast containment)– Security device


What is this router’s role?What is this router’s role?

Gateway to Internet



WAN link to a remote site in the company

San FranciscoNetwork

San JoseNetwork



Backbone access

Science Dept

EngineeringDept

BusinessDept



“Collapsed Backbone”

Science Dept

EngineeringDept

BusinessDept

Administration Dept

RemoteOffice



Network segmentation device

192.168.4.0net

192.168.5.0net



Network segmentation device(linking VLANs)

VLAN1

VLAN2

VLAN1

VLAN2



Network segmentation device(linking VLANs)

VLAN1

VLAN2

ISL TrunkISL, Cisco’s Inter Switch Link, manages traffic from multiple VLANs over a single Ethernet pipe. ISL is covered in Semester 3.



Security device (firewall)

Access control rules:1. Outbound traffic to Internet: YES2. Inbound traffic from Internet: NO


Assignment: Create a Visio drawing Assignment: Create a Visio drawing showing routers in at least two of these showing routers in at least two of these roles. Use logical network symbols.roles. Use logical network symbols.

• Network Edge– WAN links to other sites in the enterprise– WAN gateway to Internet

• Network Core– Backbone links– Collapsed backbone

• Anywhere– Network segmentation device– Security device

CISCO NETWORKING ACADEMY Chabot College ELEC 99.08 Router Introduction.

Documents

cisco networking academy

router introduction

cisco router console

series router

wan slide

mbs cisco

cisco routers

e1 slide