Docstoc

CCNA3 Chapter 1 Introduction to Classless Routing

Document Sample
CCNA3 Chapter 1 Introduction to Classless Routing Powered By Docstoc
					                                 CISCO NETWORKING ACADEMY PROGRAM

                 CCNA3: Switching Basics and Intermediate Routing v3.0




Introduction to Classless Routing

              VLSM
           RIP Version 2
                                  CISCO NETWORKING ACADEMY PROGRAM

                  CCNA3: Switching Basics and Intermediate Routing v3.0




Introduction to Classless Routing

     Variable Length Subnet Masks
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                                Classful Routing
    •    IP Version 4 provides Classes A, B, C
    •    Limited Number of unique network addresses
    •    Complex Routing tables
    •    No subnet information sent in routing updates by
         classful routing protocols e.g. RIP v1, IGRP




Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                                        Problem 1a
    • FSF Ltd has been
      allocated a class C                                                      Head
      address                                                                  Office

    • It has 3 branch offices
      with a requirement of
      10 hosts per network
      connecting via point to
      point links to the Head
      Office with 25 hosts
    • Design a subnet mask
      for FSF
Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                                       Problem 1b
    • FSF Ltd plans
    • 3 additional branch offices
      (10 hosts per LAN)
    • Head Office (25 hosts)

    • Design a new subnet mask




Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                         Problem 1b continued
    Variable Length Subnet Mask
    • Use 27 bit mask for head office (5
      host bits = 32 hosts)
    • Use 28 bit mask for branch offices
      (4 host bits = 16 hosts)
    • Use 30 bit mask for router to router
      links (2 host bits = 4 hosts)

    • Using 192.168.200.0 write out the
      addressing scheme for this
      network


Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                                         Problem 2
    • Most class A & B network addresses allocated
    • PHS Ltd with 800 hosts wants IP addresses for
      its network
    • 4 different Class C network addresses needed
    • 4 routing table entries for that network




Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                              Solution 2 – Part 1
    • ISP allocates 212.23.24.0 to 212.23.27.255
    • Routing table entry for PHS is
          – 212.23.24.0 /22 OR
          – 212.23.24.0 255.255.252.0
    • 22 bit mask in binary:
          – 11111111.11111111.11111100.00000000
    • This mask groups 4 class C networks into 1
      network & routing table entry

Chapter 1 – Introduction to Classless Routing
                                                                    CISCO NETWORKING ACADEMY PROGRAM

                                                    CCNA3: Switching Basics and Intermediate Routing v3.0




                                Solution 2 – Part 2
          – 11010100.00010111.00011000.00000000 (Network)
          – 11111111.11111111.11111100.00000000 (Mask)

           128     64      32      16      8    4      2      1       24
           0       0       0       1       1    0      0      0

           128     64      32      16      8    4      2      1       25
           0       0       0       1       1    0      0      1

           128     64      32      16      8    4      2      1       26
           0       0       0       1       1    0      1      0

           128     64      32      16      8    4      2      1       27
           0       0       0       1       1    0      1      1

Chapter 1 – Introduction to Classless Routing
                                                                   CISCO NETWORKING ACADEMY PROGRAM

                                                   CCNA3: Switching Basics and Intermediate Routing v3.0




                                         Problem 3
    • PHS Ltd has 4 class C address blocks allocated
    • It does not want to waste the addresses it has been
      given
    • The network administrator has the following
      requirements based on current use & future growth
      needs

    Head Office - 500 hosts                     Factory - 50 hosts
    Logistics Centre – 80 hosts                 Customer support Centre – 220 hosts

    Question:
    What is the appropriate VLSM mask solution for PHS Ltd?
Chapter 1 – Introduction to Classless Routing
                                                                          CISCO NETWORKING ACADEMY PROGRAM

                                                          CCNA3: Switching Basics and Intermediate Routing v3.0




                           Solution 3 (example)
                                                          Internet                     List the addresses
                          212.23.24.0 /22
212.23.24.0 /23
                                                       Head Office                     1.   On interfaces
                                                                                       2.   On each site
                  212.23.27.0 /30                            212.23.27.8 /30
                                                                                       3.   Still available
                                        212.23.27.4 /30

      Customer                                                                 Logistics
      Services                                     Factory




              212.23.26.0 /24       212.23.27.64 /26        212.23.27.128 /25




Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




       Requirements for classless routing
    • Classless routing protocol e.g. EIGRP, OSPF,
      RIP v2
    • Contiguous network addresses to allow route
      aggregation




Chapter 1 – Introduction to Classless Routing
                                 CISCO NETWORKING ACADEMY PROGRAM

                 CCNA3: Switching Basics and Intermediate Routing v3.0




Introduction to Classless Routing

           RIP Version 2
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                          RIP Version 1 Review
    •    Supported by most routers
    •    Distance Vector routing protocol
    •    Metric – hop count
    •    15 hop maximum count
    •    Periodic routing updates (30 seconds)
    •    Routing updates broadcast to 255.255.255.255
    •    Uses holddown timers
    •    Does not send subnet information in updates
    •    Does not support authentication
Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                         RIP v2 enhancements
    • Sends subnet information in updates – supports
      CIDR & VLSM
    • Supports authentication
    • Updates multicast to 224.0.0.9




Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                          IOS RIP v2 Command
    •      Enable RIP v2
    Router(config)#router rip
    Router(config-router)#version 2
    Router(config-router)#network 10.0.0.0




Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                Verifying Routing Protocols
    • Check the configuration of routing protocols
    Router#show ip protocols
    Router#show running-config

    • Viewing RIP updates
    Router#debug ip rip




Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                            Configuring Routes
    • Static Routes
    Router(config)#ip route 192.168.2.0
      255.255.255.0 192.168.1.1
    ip route destination network gateway


    Default Route
    Router#ip route 0.0.0.0 0.0.0.0 192.168.1.1
    • Defines the default gateway for all routes
    • Keeps routing tables small
Chapter 1 – Introduction to Classless Routing
                                                                CISCO NETWORKING ACADEMY PROGRAM

                                                CCNA3: Switching Basics and Intermediate Routing v3.0




                                 Default Network
    • 1 router on a network must have a default route
      on the network e.g.
    Router#ip route 0.0.0.0 0.0.0.0 192.168.1.1


    • Other routers can have a default network set
    Router#ip default network 192.168.1.0
    Traffic for destinations outside of the LAN will be sent to the
      router with the network address 192.168.1.0


Chapter 1 – Introduction to Classless Routing
                                                                  CISCO NETWORKING ACADEMY PROGRAM

                                                  CCNA3: Switching Basics and Intermediate Routing v3.0




                                                Labs
    •    1.1.4 Calculating VLSM Subnets
    •    1.2.3 Review of Basic Router Configuration with RIP
    •    1.2.4 Converting RIP v1 to RIP v2
    •    1.2.5 Verifying RIP v2 Configuration
    •    1.2.6 Troubleshooting RIP v2 using Debug




Chapter 1 – Introduction to Classless Routing

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:48
posted:11/4/2011
language:English
pages:20