2. CISCO NETWORKING ACADEMY Chabot College ELEC 99.08 Router Introduction

3. CISCO NETWORKING ACADEMY What is a Router? A special purpose computer Hardware and software dedicated to path selection and packet switching Cisco routers derived from Unix computers

4. CISCO NETWORKING ACADEMY PC vs. Router Temporary Storage (volatile) RAM RAM - Random Access Memory DRAM - Dynamic Random Access Memory Contents are lost when router is powered off.

5. CISCO NETWORKING ACADEMY PC vs. Router Long-Term Storage (non-volatile) Hard DiskNVRAM Non Volatile RAM Contents are saved when router is powered off.

6. CISCO NETWORKING ACADEMY PC vs. Router Serial Communications Serial Interfaces (COM1,COM2) Serial Interfaces (S0, S1) Used for printers, modems Used for WAN

7. CISCO NETWORKING ACADEMY PC vs. Router LAN Communications Ethernet NIC Ethernet Interfaces (E0, E1)

8. CISCO NETWORKING ACADEMY PC vs. Router Boot Instruction Sequence ROM

9. CISCO NETWORKING ACADEMY PC vs. Router Operating System WindowsIOS Internet Operating System

10. CISCO NETWORKING ACADEMY PC vs. Router Flash memory function Stores BIOSStores IOS

11. CISCO NETWORKING ACADEMY PC vs. Router User interaction Monitor Keyboard Mouse Terminal (connects to console port via “rollover” cable)

12. CISCO NETWORKING ACADEMY What is a Terminal? User box –Monitor –Keyboard –Serial port (connects to host) Has no: –CPU –Storage –Operating system

13. CISCO NETWORKING ACADEMY 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.

14. CISCO NETWORKING ACADEMY Router Port Summary Serial Interfaces –WAN links –Names: S0, S1 –V.35 Cable Ethernet Interfaces –LAN links –Names: E0, E1 –Transceiver / Twisted-pair cable

15. CISCO NETWORKING ACADEMY Router Port Summary Console Port –Terminal connection to configure router –Name: con0 –Rollover cable Aux Port –Modem connection to configure router –Name: aux0 –Rollover cable

16. CISCO NETWORKING ACADEMY Router Port Summary Virtual Terminal ports –Virtual, not physical ports –Users reach these ports via Telnet –Names: vty0, vty1, vty2, vty3, vty4

17. CISCO NETWORKING ACADEMY Router Capabilities Main Functions –Path selection –Packet switching Additional Functions –Broadcast containment –VLAN links –Security / Access control

18. CISCO NETWORKING ACADEMY Router 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

19. CISCO NETWORKING ACADEMY Router Roles 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.

20. CISCO NETWORKING ACADEMY Router Roles 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

21. CISCO NETWORKING ACADEMY Router Roles 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

22. CISCO NETWORKING ACADEMY Router Roles “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.

23. CISCO NETWORKING ACADEMY Router Roles 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

24. CISCO NETWORKING ACADEMY Router Roles Security device –Access control rules allow router to control traffic between: networks subnets switch VLANS –Traffic regulated by “Access Control Lists”

25. CISCO NETWORKING ACADEMY Router Roles 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

26. CISCO NETWORKING ACADEMY What is this router’s role? Gateway to Internet

27. CISCO NETWORKING ACADEMY What is this router’s role? WAN link to a remote site in the company San Francisco Network San Jose Network

28. CISCO NETWORKING ACADEMY What is this router’s role? Backbone access Science Dept Engineering Dept Business Dept

29. CISCO NETWORKING ACADEMY What is this router’s role? “Collapsed Backbone” Science Dept Engineering Dept Business Dept Administration Dept RemoteOffice

30. CISCO NETWORKING ACADEMY What is this router’s role? Network segmentation device 192.168.4.0 net 192.168.5.0 net

31. CISCO NETWORKING ACADEMY What is this router’s role? Network segmentation device (linking VLANs) VLAN 1 VLAN 2 VLAN 1 VLAN 2

32. CISCO NETWORKING ACADEMY What is this router’s role? Network segmentation device (linking VLANs) VLAN 1 VLAN 2 ISL Trunk ISL, Cisco’s Inter Switch Link, manages traffic from multiple VLANs over a single Ethernet pipe. ISL is covered in Semester 3.

33. CISCO NETWORKING ACADEMY What is this router’s role? Security device (firewall) Access control rules: 1. Outbound traffic to Internet: YES 2. Inbound traffic from Internet: NO

34. CISCO NETWORKING ACADEMY Assignment: Create a Visio drawing showing routers in at least two of these 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