Lab. 6 Router

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28 Οκτ 2013 (πριν από 3 χρόνια και 5 μήνες)

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1

L
ab.

6 Router

1.

Objective

A.

Study a simple int ernet

net work confi guration
and understand
how to make use of
commercial

equipments
in the
network
c
on
figuration.

B.

U
nderstand

a
n

LANE tech
nique
and
how to
construct

a
n

LANE
net work

with
the
ATM
-
LANE technique.


C.

Cons
truct a router network connecting subnetworks and understand

how it works.



2.

Basic Theory

(1)

Network
S
ystem

(1)

Configuration of Network Equipment
s

Fig
.

1 shows
a
network
configuration

consisting of routers and a switch

in the
laboratory


Fig.1
Network Configurati on


KAIST backbone is an emulated LAN
. It is
composed of
a
n

LANE

(LAN
Emulation)

and

called

vnetman

.
It

support
s

a data rate of

100Mbps
.

A
nother
network
connected to the KAIST backbone is also

an emulated LAN. It is called

e
xp

.
T
he

exp


network
consists of
Catalys
t 5500 switch and 2 Cisco 7206
r
outers
.

A
n

LANE consists of

an

LECS

(LANE Configuration Server)
,

an

LES (LANE
Server), and

LEC
s

(LANE Client).
A
n

LECS sets up the LANE.

A
n

LES

manages
the LANE and
a
n

LEC

i
s
a

clien
t of

the
LANE
.


2

Catalyst 5500 switch
is
a
n

LEC to

vnetman


(
KAST b
ackbone),

and
plays a
role of
LECS and LES to

exp

. Cisco 7206 router plays a part

of LEC to

both


vnetman


and

exp

.
A
nother
Cisco 7206
router
is a
n

LEC to

exp

.

Al though
Catalyst 5500 s
witch
is

located

between

vnetman


and

exp

,

one
of 2 Cisco 7206 routers plays a

part

of gateway between KAIST b
ackbone and
the

experimental

network because Catalyst 5500 switch do
es not

have a
routing function.



(2)

Introduction of Network Equipment
s



Catal
yst 5500 Switch


Fig.2 Catalyst 5500
s
witch


The Cisco Catalyst 5500
s
witch is a high
-
end modular switching platform that
provides the scalab
ility, flexibility, and redundancy required for building large,
switched intranets and can be used in both wiring closet and backbone
applications. It has 13 slots and a gigabit Ethernet
-
ready architecture that scales
to more than 50 Gbps and throughput of

tens of millions of packets or cells per
second (pps).

The Cisco 5500 complies with Cisco's Investment Protection standards by
seamlessly integrating features and interface modules from the Catalyst 5000,
8500, and Cisco Lightstream 1010 products. With it
s support for hot
-
swappable

3

modules, power supplies, and fans, the Catalyst 5500 delivers high availability for
production networks. Dual redundant switching engines, power supplies, and a
passive backplane design ensure full system redundancy for mission
-
critical
environments.

Catalyst 5000 Family features a Gigabit Ethernet and ATM
-
ready platform
offering users high
-
speed trunking technologi
es, including Fast Ether
net
Channel

and OC
-
12 ATM. The Catalyst 5000 series also features a redundant architecture,
dynamic VLANs, complete intranet services support, and media
-
rate per formance
with a broad variety of interface modules.

Modules for th
e Catalyst 5000 family
are designed for complete interoperability
and investment protection. Catalyst 5000 family suppor
ts multiprotocol NetFlow
Switching for scalable convergence of Layer 2 and Layer 3 switching, adding the
benefits of mul tiprotocol, mul tilayer switching and other Cisco IOS network
services.

The range of media support in the Catalyst 5000 family enables n
etwork
managers to deliver high
-
per formance backbone access to accommodate Web
browser
-
based traffic across the intranet. A variety of inter face modules operate
s

in any Catalyst 5000 family switch to deliver dedicated bandwidth to users through
high
-
densit
y group switched 10BaseT or 100BaseT Ethernet; flexible
10/100BASE
-
T Ethernet, fiber
-
based Fast Ethernet, and Fast Ether
net
Channel;
Token Ring; CDDI/FDDI; ATM LAN Emulation (LANE) and Multiprotocol over ATM
(MPOA); the Route/Switch module (based on the Ro
ute/Switch Processor for the
Cisco 7500 series router); and Gigabit Ethernet. Unique to the Catalyst 5500
Series are the ATM Switch Processor and ATM switch interface modules and port
adapters.











Cisco 7206 VXR Router


4


Fig.
3 Cisco 7206 VXR
r
outer


The Cisco 7200 VXR routers are the mul tiservice members of the Cisco 7200
series routers. The Cisco

7200 VXR routers are designed to support gigabit
capabilities and to improve data, voice, and video integration in both service
provider and enterprise environments. The Cisco 7200 VXR routers incorporate an
integrated Multiservice Interchange (MIX) capab
ility to support future voice
applications. MIX interconnections on the midplane provide the ability to switch
DS
-
0 time slots between multichannel T1 or E1 inter faces, much like a digital
cross
-
connect or an add
-
drop mul tiplexer. This feature enables the
Cisco 7200
VXR routers to switch DS
-
0 voice channels on a T1 or E1 inter face from one voice
processing port adapter to another voice processing por
t adapter. It also enables
DS
-
0

to be switched through the Cisco 7200 VXR routers without any processing,
a r
equirement in certain voice configurations. The Cisco 7200 VXR routers support
a high
-
speed network services engine (NSE) as well as the high
-
speed network
processing engine, NPE
-
400, and all other available network processing engines.
The NSE
-
1 is a combi
nation of a high
-
per formance RISC processor and high
-
performance PXF processor. The PXF processor works with the routing processor
to provide accelerated packet switching, as well as accelerated IP Layer 3 feature
processing. The Cisco 7200 VXR routers als
o support high
-
speed network
processing engines (NPEs) to provide increased routing and process switching
performance. The Cisco 7206VXR supports mul tiprotocol, mul timedia routing and
bridging with a wide variety of protocols and port adapter combinations
available
for 7200 series routers. In addition, the Cisco 7206VXR midplane provides
increased support for multiple high
-
bandwidth port adapters.

The Cisco 7200 combines exceptional price/performance with the widest range
of connectivity options and unmatch
ed feature support. This compact router
provides industry
-
leading serviceability and manageability features coupled with

5

high
-
per formance modular processors including the Cisco 7200 NPE
-
G1
Processor. By leveraging the modularity of the Cisco 7200, customer
s can deploy
scalable solutions to address a wide range of density, per formance and service
requirements while ensuring investment protection for future network needs.



(2)

Internet Routing Architecture



Fig.4 Structure of the internet ro
uting


Ind
ividual networks may be
connected

together by a router, which acts as a
switch between the networks. The router operations are programmed to rout
e

the
traffic to the proper network by
checking

the

destination address
of

packet
s

and
matching the a
ddress with entries in a routing table. Those entries
indicate

the
best route to the next

hop

network or destination host.
Fig. 4 shows the s
tructure
of the internet routing
.

Even though l ocal authorities may administer these individual networks, it is
com
mon for a group of networks to be administered as a whole system. This
group of networks is called an
autonomous system

(AS). Examples of
AS
s are
networks located

on sites such as college campuses, hospital complexes, and
military installations. The networ
ks located at these sites are connected together
by a router, and since these routers operate within an
AS
, they often choose their
own mechanisms for routing data. Fig
.5

shows the layout of the
AS
.



6


Fig.5 Autonomous
s
ystems and
r
outing

d
omai n


The local administrative
authorities in the ASs agree on how they provide
information to each other regarding the

reachability


of the hosts inside the ASs.
The advertising responsibility can be given to one router, or a number of routers
may par
ticipate in the operation.

The A
S
s are identified by
AS
numbers. How this is accomplished is up to the
administrators, but the idea is to use different numbers to distinguish different A
S
s.
Such a numbering scheme might probe helpful if a network manager d
oes not
wish to route traffic through an AS. The AS might be accessible to the manager

s
network, but it may be administered by a competitor, it may not have adequate or
proper security services, etc.
Using

routing protocols and numbers identifying A
S
s,
th
e routers can determine how they reach each other and how they exchange
routing
information
.

A
S
s are identified with AS numbers assigned from 1 to 65,535, with 1 to 65,41
1

for registered Internet numbers, and 65,412 to 65,535 is for private numbers.

Fig
.5

il lustrates

internal and external gateway protocols. When ARPAnet was first
implemented, it consisted of a single backbone network. With the implementation
of Internet, ARPAnet then provided attached routers to local networks. A protocol,
called the Gatewa
y
-
to
-
Gateway Protocol(GGP), was used for these routers to
inform each other about their attached local networks. Traffic passing between
two l ocal networks passed through two routers, and each router had complete
routing information about the other core ro
uter
.

Since these routers had complete
routing information, they did not need a default route
.
However, things

were

changed as the Internet grew. Therefore, the concept of a router holding complete
routing
information

on an internet became too unwieldy.

To

approach this problem, routers were given responsibilities for only a part of
an internet. In this manner, a router did not have to know about all other routers of
an internet but relied on neighbor routers and/or routers in other A
S
s to reveal

7

their rout
ing information. Indeed, if they had
insufficient

knowledge to make a
routing decision, they simply chose a defaul t route. This change gave rise to two
other terms:
exterior routers and interior routers
. As exterior router is so named
because it supports t
he exchange of routing
information

between different A
Ss.

Representative EGP(Exterior Gate
way

Protocol)s
include

RIP

and

OSPF. Interior
routers are so named because they belong to the same AS and exchange
information

within the AS.

Representative IGP(Inter
ior Gate
way

Protocol) i
nclude

BGP.



(3)

LANE (LAN Emulation)


Fig.6 Protocol
S
tructure of LANE


Fig.6
illustrates the protocol structure of LANE 1.0. The LANE 1.0
specification

defines a software interface for network layer protocols identical to that of

exi
sting
LANs that encapsulate

user data in either an Ethernet or Token Ring M
a
c frame.
LANE dose not emulate the actual media access control protocol of a particular
LAN concerned. Instead, LANE defines thr
ee servers that
access

over a number of
ATM connecti
ons designated for specific control and data transfer purpose.

LANE 1.0 dose not directly define support for FDDI; however, devices readily
map FDDI packets into either Ethernet or Token Ring using existing translation
bridging techniques. Since the two n
ew 100
-
Mbps LAN standards use existing
MAC packet formats, they map directly into LANE Ethernet or Token Ring formats
and procedures. As described above, LANE literally bridges ATM and LANs by
interworking at the Media Access Control (MAC)

layer, which pro
v
ides device
-

8

driver interface such as Open Data
-
Link Interface (ODI) and Network Driver
Interface Specification (NDIS) to higher
-
level applications.

The ATM Forum

s LANE 1.0 specification defines operation over the ATM best
effort, or UBR service class sim
ilar to existing LANs. The LANE 2.0 specification
adds QoS guarantees, giving ATM based LAN Emulation a
distinguishing

characteristic over most other LAN protocols.



(4)

Overview of experiment


Fig
.7

Network con
figurati on

for experi ment


3 network

equipments

and
2 PCs are used for experiment. You

can

use IP
address from
143.248.189.0 ~ 143.248.189.255
. In other words, you

can only use
143.248.189 net
wor k
. In this experiment,
you must

divide
4 subnets and use 3
subnets
among

them
. Fig.7 shows the network con
fi
guration

for

this

experiment.


9

3

Pre
-
Lab

(1)

Investigate the

KAIST network

configuration

and describe
it.

(2)

Explain ILMI (Interim Local Management Interface Specification) used in ATM net work
management
,
and the role of ILMI in LANE

(3)

Survey the limit
ations

of LANE

and describe
it
.

(4)

32 bits are used as address space in IPv4. Survey

the

IP address system defined in
IPv4 in detail. (e
g.

C
lass A,

B)

(5)

As mentioned
above
, Internet

net work

consist
s

of a large number of AS

s.

Hierarchical
routing is required
to implement eff
icient routing in the
internet
network
. Explain the
routing hierarchy,

many
kinds of routing protocol
s
,

and function
s

of each routing
protocol


(6)

Cisco
develop
ed

some routing protocol.
W
idely
-
known Cisco routing prot ocol
s are

IGRP(Inter
-
Gateway Routing Proto
col ) and EIGRP(Enhanc
e
d IGRP). Survey IGRP and
EIGRP.
C
ompare
these

protocol
s

and describe the difference
s
.

(7)

In this
experiment
,
you

set

up an

LANE with connecting commercial router
s

and

an

ATM
switch to PC used as a cons
ole.
The f
ollowing

commands are used

to configure Cisco
7206 VXR Router
s

and Cisco Catalyst 5500. You should be well aware

of the foll owi ng
commands

(instructions)

before lab.



e
nable



c
onfig terminal



i
nterface



I
P

address x.x.x.x m.m.m.m



s
how running
-
config



w
rite memory



e
xit

(8)

If you determine t
he network

policy, the experiment can be easily
completed



10

4

Main Lab




Procedure of
E
xperiment

(1)

Using
the
above

mentioned
commands

(
instruction
s
)
, confirm the

initial

network

configuration of all equipment
s
. This is
required to re
turn

all equipments

to the

initial
network configuration

after the experiment.

(2)

Determine
how to
separate

4 subnets

from
the
allocated IP address

space
.

(3)

Configure

a

topology like Fig.
7

using

the
policy

determined

in
(2)
.

(4)

Co
mplete

a
network
confi guration
between the router
s

and PC
s

a
ccording to the policy
in

(2)
.

(5)

Connect
a
console to

a

router and
complete the IP address of
the

router

s interface
.


(6)

Connect
a
consol e to ATM switch and complete the IP address of each router

s
interface and routing table
considering
the policy
determined
in
(2)
.

(7)

After completing the network configuration

following the steps (1) through (5)
, you

should

test the communicati on between PCs connected to rout er
.

Using

a

ping program
in
W
indows OS, send
a
pi ng message from PC1

to PC2 and
PC2 to PC1, and

w
rite
tes
t
results.

(8)

After

the
test

of network connection using

a

ping program,

confirm the rout e between
two hosts

using

a

tracert program,



11

Fig
.8

Detailed
N
etwork
C
on
figurati on for This E
xperi ment




Main Report

(1)

Refer to Fig.
8

and explain the IP address
ing

policy used in this experiment

(2)

A
ttach the initial network
configuration

parameters

during the experiment step (1)
.

(3)

Using

the

router instructions

obtained in Pre
-
Lab
, confirm the configuration of r
outer1
and save the captured configuration. You should attach the configuration in the report
and compare the
result

with

that of (2).

C
heck

the difference and explain the reason.

(4)

Attach the routing table of the ATM switch and
describe

it.

(5)

Attach the resul
ts of ping and tracert test
s
, and
describe

them.

(6)

Explain

the

principle
s

of

the

ping and tracert program
s

used to test the network
connect
i
vity

between hosts.

(7)

Explain

the

protocols used in

the

ping

and tracert
program.



5

Conclusion

(1)

Describe

difficulties and

problem
s

during experiment
.

(2)

In this lab,
you

learn the simplest model of LANE using ATM switch. Find
a

similar
technology to LANE and describe the princip
le
briefly
.



6

Reference

[1]

Network Layer Switched Services

, Daniel Minoli, Andrew Schmidt, Wiley

[
2]

Cisco 7206 Installation and Configuration Guide


[3]

ATM

, McDysan, Spohn, Mc Graw Hill

[4]
http://www.cisco.com/univercd/cc/td/doc/product/core/7206/index.htm

[5]
http://www.atmforum.com

[6]

IP Routing Protocols

, Uyless Black, Prentice Hall

[7]

CISCO IOS 12.0 Solutions for Network Protocols Vol.I

, CISCO Systems



** You should prepare

for a s ingle

floppy disk when you atte
nd lab.