Finish up from Tuesday:

reekydizzyNetworking and Communications

Oct 28, 2013 (4 years and 15 days ago)

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Finish up from Tuesday:

Routing Basics

Today’s Agenda…


Chapter Seven


IP Routing (Chapter 5 Sybex)


Chapter Eight


Router Configuration and Internetwork Management
(Chapter 7 Sybex)


Chapter Nine


Configuring Novell IPX (Chapter 8 Sybex)


Chapter Ten


Access Lists (Chapter 9 Sybex)


Chapter Eleven


Wide Area Network (Chapter 10 Sybex)

Overview


What is IP Routing?


The IP Routing Process


Static Routing


Configuring Static Routes


Default Routing

Static, Default & Dynamic


Routers learn paths to other
networks in 3 ways:


Static Routing
: manual configuration
of routes in route table


Default Routing
: Used as the Default
Gateway when no entries in the route
table match destination address
(manually configured) . Gateway of last
resort


Dynamic Routing
: uses protocols such
as RIP to automate the creation and
updating of a route table

Configure Static Routes

Where do you want to go?

The remote network


IP Command

Remote Network

Subnet Mask

Next Hop

IP Route

172.15.50.0

255.255.255.0

172.15.20.2


How do you get there?

Via the next hop or interface


Router(config)#
ip route
172.15.50.0

255.255.255.0

172.15.20.2

Destination

Network

Subnet

Mask

Next Hop Address

Or

Exit interface

Default Routing


Also known as the Router or Gateway of Last Resort


Router(config)#
ip route 0.0.0.0 0.0.0.0 172.16.20.2

Interior Routing Protocols


Distance
-
Vector

understands only the distance
and direction to any network connection on the
Internetwork.


RIP



a distance
-
vector routing protocol


IGRP



(Internet Gateway Routing Protocol) Cisco’s
proprietary distance
-
vector routing protocol



Link
-
State

understands the entire network
better than distance
-
vector and never listens to
secondhand information.


OSPF



a link
-
state routing protocol


EIGRP



(Enhanced Internet Gateway Routing Protocol)
Cisco’s balanced distance
-
Vector routing protocol

Distance
-
Vector

RIP

IGRP

30 Second update

90 second update

Uses only hop count

Uses on hop count

Sends entire routing


tables

Sends entire routing


tables

max 15 hops

max hops 255

u update: 30 seconds

Metrics: 1


255

6u invalid: 180 seconds


list as invalid

Delay: Units of 10 ms

8u Flush: 240 seconds


Flush off list

Load: Factions of 255 / 0 = No load

Update 90 seconds

Invalid 3u

Holddown 3u+10

Flush

7u

Slow Convergence

Distance
-
Vector

Bandwidth: 1200


10 Gbps

Reliability: fractions of 255

Link
-
State

OSPF

EIGRP

2 hr update

2 hr update

Uses shortest or

fastest path

Uses shortest

or fastest path

Use LSP

(packets)

Use LSP

(packets)

Sends only

changes to all

routers

Sends only

changes

Link State

Fast Convergence

RIP


RIP Timers


Routing Update Timer
30 seconds


Route Invalid Timer

180 seconds


Route Flush Timer

240 seconds

IGRP


Cisco proprietary Distance
-
Vector



IGRP Routes:


Interior


Between subnets


System


Within AS


Exterior


Outside the AS

Administrative Distances


Default Administrative Distances


Directly connected Interface

0


Static Route

1


EIGRP

90


IGRP

100


OSPF

110


RIP

120


Unknown

255 (will never be used)

OSPF


Based on link
-
state algorithm


Deployed within an autonomous system


Network administrators may assign costs
to a particular link, maximum metric limit
65535


Uses multicast every 2 hours


Routing update packets can efficiently
carry information for more than one router


Can receive and send routes to other AS


Also: Type of Service routing, one or more
metrics, variable length subnet masks
(VLSMs)

IGRP Operating Stability


Multipath routing


Holddowns


Split
-
Horizons


Poison reverse updates

IGRP


Operating Stability


Update Timers


Invalid Timers


Holddown timers


Flush timers

Practice


Configuring RIP Routing (pages 26


28)


IP Addressing example (page 29)


Test IP Address configuration (pages 30


31)


Enable Routing (page 31)


Monitoring RIP (page 32)


Configuring and Monitoring IGRP Routing (page
33)

Lab and Review


Lab Pages 306


308


Questions Pages 309


315

Chapter Eight

Router Configuring and
Internetwork Management

Overview


Cisco IOS Commands


Sources for Cisco IOS Software


TFTP Server


Fallback


Cisco Auto
-
install Procedure


Accessing Other Routers


Basic Testing

Show Version


The current version of the Cisco IOS


Router uptime


How the system was started


Where the system was loaded from


Processor type and RAM


Interfaces detected by POST


Flash memory


Configuration register setting

Show Flash


Name of files loaded in flash


Size of files loaded in flash


Free space available in flash

Show Running
-
config


Displays the current running
configuration commands
programmed in the router


Global configuration commands


Interface configuration commands


Line configuration commands

Show startup
-
config


Displays the configuration commands
stored in NVRAM


Global configuration commands


Interface configuration commands


Line configuration commands

Show Interfaces


All hardware interfaces installed on the
router


The status of the interfaces


The type of cable attached to the interface


The routing metrics associated with the
interface


Protocol encapsulation of the interface


Queue status of the interface


Packet statistics of the interface

Show Protocols


Displays


Which protocols are configured on the
router


What ports the protocols are configured
on


The protocol address for each port


The status of the port

Show IP Protocols


The routing protocol


The timers for the protocol


Filter lists applied


Networks being routed


Source of routing information


Administrative distance

Backing up and Restoring


Copy Flash TFTP


Makes a copy of the contents of Flash
onto a file on the TFTP server


Copy TFTP Flash


Restores the copy on the TFTP server
into the Flash

Backing up and Restoring


Copy Run TFTP


Saves a copy of the running
-
config on
the TFTP server


Copy TFTP Run


Restores the copy of Running
-
config on
the TFTP server to your router

Configuration Registry


16 bits of the configuration registry
are read 15
-
0, from left to right


The default configuration registry on
Cisco routers = 0 x 2102


0x always precedes hexadecimal in
Cisco


0 x 2101 Boot Image from ROM


Mini OS in ROM is RxBoot


To get into ROMMON, press

‘BREAK’

key within 60 seconds of startup

Cisco Discover Protocol CDP


Proprietary Cisco Protocol


Uses
SNAP

(Subnetwork Access Protocol) at data
link layer


Network layer protocol independent


Uses broadcasts to discover neighboring routers


Displays information about upper layer protocols
(IP, IPX, etc)


Updated information from broadcasts replaces old
information immediately


Sends a broadcast every 60 seconds and holds
the info for 180 seconds

Show CDP


Show cdp interface


Show cdp entry *


Show cdp neighbors


Show cdp neighbors detail

Resolving Hostnames


Two ways:

1.
Static

2.
Dynamic

Testing


Test by telneting into another router:


Routers must have vty passwords enabled.


Test with Ping


Seven possible response desplay

!


Successful receipt of an echo reply

.


Time out

U


Destination unreachable

C


Congested experience packet

|


Ping interrupted (ctrl
-
shift
-
6 x)

?


Packet type unknown

&

Packet time
-
to
-
live exceeded

Testing


Traceroute or Trace
for short


Five possible responses

!H

The Router received the probe but didn’t
forward it because of an access list

P

The protocol was unreachable

N

The network was unreachable

U

The port was unreachable

*

There was a time
-
out

Lab and Review


Lab pages 393


398


Questions pages 399


404

Chapter Nine

Configuring Novell IPX

Overview


Introduction to Novell IPX


Enabling IPX on Cisco Routers


Monitoring IPX on Cisco Routers

Compare IP with IPX

IP vs. IPX logical addressing

Protocol

Network

Interface/Node

Example

TCP/IP

Uses up to 30 bits
to indicate the
network number

The number of bits
used for the node is
dependent on the
number of bits used
for the network.

172.29.15.4

172.29 = Network

15.4 = Node

Novell
IPX

Uses up to 32 bits
to indicate the
network address.
Can be up to 8
hexadecimal
characters.

Uses the 48


bit 8
hexadecimal MAC
address.

8BCDF45E.0011.0434.44FF

8BCDF45E = Network

0011.1434.44FF = Interface


IPX Protocol Stack

On the OSI

NCP,

SAP

Physical

Data Link

Network

Transport

Session

Presentation

Application

SPX

IPX, RIP, NLSP
*

MLIO, ODI

Netware Control Protocol


-

humble Protocol


-

Provide Network Services

60 Second Updates

Connection Orientated Segments

Connectionless Packets/Datagrams

MLID equivalent to NDIS (NIC’s)

Client


Server


Netware Clients need servers to
locate resources.


GNS


SAP


Cisco Routers also build SAP tables
so they can respond to GNS
requests.

Server


Server


SAP and RIP communications between
servers


RIP and SAP are broadcast every 60
seconds


Cisco routers do not pass SAP
broadcasts


Routers build SAP tables and broadcast
summarized information


Routers build IPX RIP routing tables

IPX Addressing


00007C80.0000.8609.33E9





RIP



servers build routing tables that contain entries for
the networks they are directly connected (every 60
seconds)


SAP



(service advertising protocol) NetWare servers use
SAP to advertise the services they offer every 60 seconds.

Network

32 Bits

Node (MAC
Address)

48 bits

Encapsulation


Encapsulation (or framing)

is the process of
taking Packets from upper layer protocols and
building frames to transmit them across the
network


Multiple encapsulations

on same media are
supported. (Each requires a unique network
number)


You can configure more than 1 encapsulation
type on an interface, however, all
nodes/interfaces have to have a common
encapsulation type to communicate


IPX/SPX “Chatty Protocol”



each
encapsulation type that is configured will
broadcast across network every 60 seconds

Enabling IPX Routing


Pages 9


14

Lab and Review


Lab pages 447


451


Questions pages 452


458

Chapter Ten

Access Lists

Overview


Standard IP Access Lists


Extended IP Access Lists


Displaying Access List Information



Standard IPX Access Lists


Extended IPX Access Lists


IPX SAP Filters

What are Access
-
Lists?


“An Access list is essentially a
list of conditions that control
access both to and from a
network segment.”

Two Kinds…


STANDARD Access Lists:



Uses only Source IP.


Permits or denies an entire suite of
protocols.


IPX, however, can filter on both source and
destination IPX address.



EXTENDED Access Lists:



Uses both Source IP and Destination IP


Protocol Field in the Network layer header
and Port numbers at the Transport layer
header.

Access
-
List permit or deny

Match

First

Case?

PERMIT

PERMIT

PERMIT

Match

Next

Test(s)?

Match

Last

Test?

DENY

DENY

DENY

N

Y

Y

Y

Y

N

N

DENY

Y

Y

Implicit Deny

Destination


Interface(s)

Packet

Discard

Bucket

Packet to Interface(s)

in the Access Group

Identify Access
-
Lists

Access List Type

Number
Range/Identified

IP Standard


Extended

1


99

100


199

IPX Standard


Extended


SAP
filters

800


899

900


999

1000


1099

AppleTalk

600


699

Configure Standard Access Lists


Pages 7


8

Wildcard Masking


Wildcards are used with access lists to
specify a host, network, or part of a
network


Block size

are used to specify a range of
addresses.


Example:

64, 32, 16, 8, and 4


When specifying a range, always
choose the next largest block size.


A value of “0” means the values must match


A value of “255” means any value.

Example of Wildcard Masking

Permit/Deny 150.50.0.0 0.0.255.255




0

.0

.255

.255

00000000.00000000.11111111.11111111



0

means
check

the address bit for match


octet in address must match exactly


1
means
ignore

the address bit for match


Allow permit or deny of whole address ranges



Example:


RouterA(config)#access
-
list 1 deny 150.50.40.0
0.0.255.255

Example:


RouterA(config)#access
-
list 1 deny 172.16.16.0 0.0.3.255



Access
-
list number 1


Deny


Start at network 172.16.16.0


Block size of 4


Range of 172.16.16.0


172.16.19.0

Block sizes


Size of 4 would be 0


3, 4


7, etc.


Size of 8 would be 0


7, 8


15, etc.


Size of 16 would be 0


15, 16


31,
etc.

Extended Access
-

lists


routerA(config)#access
-
list ?


Gives a list of access
-
list numbers



Extended IP Access list pages 12


16


IPX access lists pp. 18


20

Lab and Review


Lab pages 486


491


Questions pages 492
-

498

Chapter Eleven

Wide Area Network

Overview


Plain Old Telephone Service (POTS)


High
-
Level Data
-
Link Control (HDLC)


Point
-
to
-
Point Protocol (PPP)


Frame Relay


ISDN

Lab and Review


Lab pages 550


557


Questions pages 558


564