ch 7 distance vector routing protocols part 2 of 2 distance vector routing and igrp l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Ch. 7 – Distance Vector Routing Protocols Part 2 of 2: Distance Vector Routing and IGRP PowerPoint Presentation
Download Presentation
Ch. 7 – Distance Vector Routing Protocols Part 2 of 2: Distance Vector Routing and IGRP

Loading in 2 Seconds...

play fullscreen
1 / 67

Ch. 7 – Distance Vector Routing Protocols Part 2 of 2: Distance Vector Routing and IGRP - PowerPoint PPT Presentation


  • 176 Views
  • Uploaded on

Ch. 7 – Distance Vector Routing Protocols Part 2 of 2: Distance Vector Routing and IGRP. CCNA version 1.0 Rick Graziani Cabrillo College. Note to instructors.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Ch. 7 – Distance Vector Routing Protocols Part 2 of 2: Distance Vector Routing and IGRP' - darshan


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
ch 7 distance vector routing protocols part 2 of 2 distance vector routing and igrp

Ch. 7 – Distance Vector Routing ProtocolsPart 2 of 2: Distance Vector Routing and IGRP

CCNA version 1.0

Rick Graziani

Cabrillo College

note to instructors
Note to instructors
  • If you have downloaded this presentation from the Cisco Networking Academy Community FTP Center, this may not be my latest version of this PowerPoint.
  • For the latest PowerPoints for all my CCNA, CCNP, and Wireless classes, please go to my web site:

http://www.cabrillo.cc.ca.us/~rgraziani/

      • The username is cisco and the password is perlman for all of my materials.
  • If you have any questions on any of my materials or the curriculum, please feel free to email me at graziani@cabrillo.edu (I really don’t mind helping.) Also, if you run across any typos or errors in my presentations, please let me know.
  • I will add “(Updated – date)” next to each presentation on my web site that has been updated since these have been uploaded to the FTP center.

Thanks! Rick

Rick Graziani graziani@cabrillo.edu

igrp features
IGRP Features
  • IGRP is a distance vector routing protocol developed by Cisco.
  • IGRP sends routing updates at 90 second intervals, advertising networks for a particular autonomous system.
  • Key design characteristics of IGRP are a follows:
    • The versatility to automatically handle indefinite, complex topologies
    • The flexibility needed to segment with different bandwidth and delay characteristics
    • Scalability for functioning in very large networks

Rick Graziani graziani@cabrillo.edu

igrp features4
IGRP Features
  • By default, the IGRP routing protocol uses bandwidth and delay as metrics.
  • Additionally, IGRP can be configured to use a combination of variables to determine a composite metric.
  • Those variables include:
    • Bandwidth
    • Delay
    • Load
    • Reliability

Rick Graziani graziani@cabrillo.edu

igrp metrics
IGRP Metrics

Rick Graziani graziani@cabrillo.edu

igrp metrics6
IGRP Metrics
  • The metrics that IGRP uses are:
    • Bandwidth – The lowest bandwidth value in the path
    • Delay – The cumulative interface delay along the path
    • Reliability – The reliability on the link towards the destination as determined by the exchange of keepalives
    • Load – The load on a link towards the destination based on bits per second
    • NO… MTU – The Maximum Transmission Unit value of the path. MTU has never been used by IGRP or EIGRP as a routing metric.
  • IGRP has an administrative distance of 100, more “trustworthy” than RIP at 120.
  • This means a Cisco router will prefer an IGRP learned route over a RIP learned route to the same network.

Rick Graziani graziani@cabrillo.edu

administrative distances
Administrative Distances

Rick Graziani graziani@cabrillo.edu

igrp metrics8
IGRP Metrics

Rick Graziani graziani@cabrillo.edu

igrp routes
IGRP Routes
  • Interior“Interior routes are routes between subnets of a network attached to a router interface. If the network attached to a router is not subnetted, IGRP does not advertise interior routes.”
  • Clarification
  • IGRP also advertises three types of routes:
    • interior, system, and exterior.
  • Interior routes are routes between subnets in the network attached to a router interface.
  • If the network attached to a router is not subnetted, IGRP does not advertise interior routes.

Rick Graziani graziani@cabrillo.edu

igrp routes10
IGRP Routes
  • System“System routes are routes to networks within an autonomous system. The Cisco IOS software derives system routes from directly connected network interfaces and system route information provided by other IGRP-speaking routers or access servers. System routes do not include subnet information.”

Rick Graziani graziani@cabrillo.edu

igrp routes11
IGRP Routes
  • Exterior“Exterior routes are routes to networks outside the autonomous system that are considered when identifying a gateway of last resort. The Cisco IOS software chooses a gateway of last resort from the list of exterior routes that IGRP provides. The software uses the gateway (router) of last resort if a better route is not found and the destination is not a connected network. If the autonomous system has more than one connection to an external network, different routers can choose different exterior routers as the gateway of last resort.”

Rick Graziani graziani@cabrillo.edu

igrp timers
IGRP Timers
  • IGRP has a number of features that are designed to enhance its stability, such as:
    • Holddowns
    • Split horizons
    • Poison reverse updates

Rick Graziani graziani@cabrillo.edu

igrp timers13
IGRP Timers
  • The update timer specifies how frequently routing update messages should be sent.
  • The IGRP default for this variable is 90 seconds.
  • A random jitter variable of 20% is subtracted from each update time to prevent update timer synchronization.
  • IGRP updates will vary from 72 to 90 seconds.

Update timer

Rick Graziani graziani@cabrillo.edu

igrp timers14
IGRP Timers
  • The invalid timer specifies how long a router should wait in the absence of routing-update messages about a specific route before declaring that route invalid (unreachable), but still in the routing table.
  • The IGRP default for this variable is three times the update period or 270 seconds.
  • Then placed in the holddown state.
  • “If I haven’t heard from you in 270 seconds, I am considering this route as unreachable, I will start the holddown timer, but I will keep it in the routing table until the flush timer expires.”

Invalid timer

Rick Graziani graziani@cabrillo.edu

igrp timers15
IGRP Timers
  • The holddown timer specifies the amount of time for which information about poorer routes are ignored.
  • Zinin: “Holddown specifies the number of seconds that a route must spend in holddown state after expiration of the Invalid Timer.”
  • The IGRP default for this variable is three times the update timer period plus 10 seconds = 280 seconds.
  • The original route is still in the routing table but marked as unreachable, until the flush timer expires.

Holddown timer

Rick Graziani graziani@cabrillo.edu

igrp timers16
IGRP Timers
  • Finally, the flush timer indicates how much time should pass before a route is flushed from the routing table.
  • The IGRP default is seven times the routing update timer or 630 seconds.
  • Zinin: “Flush specifies the number of seconds that a route must remain in the routing table in the garbage collection state after it exits the holddown state.”
  • Each time an update is received the invalid and flushtimers are reset.
  • If the invalid timer expires before another update is heard, the route is marked as unreachable, but remains in the routing table.
  • If the flush timer then expires before another update is heard, the route will be deleted from the routing table.

Flush timer

Rick Graziani graziani@cabrillo.edu

igrp timers17
IGRP Timers
  • Update timer: how frequently routing update messages should be sent
  • Invalid timer: how long a router should wait in the absence of routing-update messages about a specific route before declaring that route invalid (unreachable), but still in the routing table
  • Holddown timer: specifies the amount of time for which information about poorer routes are ignored.
  • Flush timer: how much time should pass before a route is flushed from the routing table

My testing shows that the flush timer starts after the first 90 second update is missed.

Rick Graziani graziani@cabrillo.edu

igrp timers18
IGRP Timers
  • All timers begin at the same time.
    • Update timer = 90 seconds
    • Invalid timer = 270 seconds
    • Holddown timer = 280 seconds
    • Flush timer = 630 seconds
  • Today, IGRP is showing its age, it lacks support for variable length subnet masks (VLSM).
  • Enhanced IGRP (EIGRP) supports VLSM.

Rick Graziani graziani@cabrillo.edu

configuring igrp
Configuring IGRP
  • Same network commands as RIP.
  • IGRP “AS” number must be the same on all routers.

Rick Graziani graziani@cabrillo.edu

configuring igrp20
Configuring IGRP

timers basic (IGRP)

  • To adjust Interior Gateway Routing Protocol (IGRP) network timers, use the timers basic router configuration command. To restore the default timers, use the no form of this command.

Router(config-router)#router igrp 100

Router(config-router)#timers basic update invalid holddown flush [sleeptime]

Router(config-router)# no timers basic

Rick Graziani graziani@cabrillo.edu

migrating from rip to igrp
Migrating from RIP to IGRP

Router(config)#router rip

Router(config-router)#network 172.16.0.0

Router(config-router)#network 192.168.1.0

Router(config-router)#exit

Router(config)#router igrp 10

Router(config-router)#network 172.16.0.0

Router(config-router)#network 192.168.1.0

Router(config-router)#exit

Router(config)#no router rip

  • Enable IGRP
  • Suggestion: Remove RIP configuration from routers even though the administrative distance will prefer RIP

Rick Graziani graziani@cabrillo.edu

verifying igrp
Verifying IGRP

Rick Graziani graziani@cabrillo.edu

verifying igrp23
Verifying IGRP

Rick Graziani graziani@cabrillo.edu

verifying igrp24
Verifying IGRP

Rick Graziani graziani@cabrillo.edu

verifying igrp25
Verifying IGRP

Rick Graziani graziani@cabrillo.edu

verifying igrp26
Verifying IGRP

Rick Graziani graziani@cabrillo.edu

troubleshooting igrp
Troubleshooting IGRP

Rick Graziani graziani@cabrillo.edu

troubleshooting igrp28
Troubleshooting IGRP

Rick Graziani graziani@cabrillo.edu

troubleshooting igrp29
Troubleshooting IGRP

Rick Graziani graziani@cabrillo.edu

domains
Domains…

Rick’s extra information on autonomous systems…(FYI only!)

Two types of autonomous systems:

1. Process domain

2. Routing domain

Rick Graziani graziani@cabrillo.edu

domains31
Domains…

Process domain

  • A single IGP (Interior Gateway Protocol) process that is autonomous from other IGP processes.

IGRP autonomous systems are also known as a process domains.

Redistribution is used to route between these types of autonomous systems.

Rick Graziani graziani@cabrillo.edu

domains32
Domains…

Routing domain

  • A system of one or more IGPs (Interior Gateway Protocols) that is autonomous from other IGP systems.
  • An EGP (Exterior Gateway Protocol) like BGP is used to route between these types of autonomous systems.

Rick Graziani graziani@cabrillo.edu

summary
Summary

But there is still more!

Rick Graziani graziani@cabrillo.edu

metric calculation
Metric Calculation

The metrics used by IGRP in making routing decisions are (lower the metric the better):

  • bandwidth
  • delay
  • load
  • reliability

By default, IGRP uses only:

  • Bandwidth
  • Delay

Analogies:

Think of bandwidth as the width of the pipe

and

delay as the length of the pipe.

  • Bandwidth is a the carrying capacity
  • Delay is the end-to-end travel time.

Rick Graziani graziani@cabrillo.edu

metric calculation37
Metric Calculation

If these are the default:

  • bandwidth (default)
  • delay (default)

When are these used?

  • load
  • reliability

Only when configured by the network administrator to do so!

IGRP also tracks (but does not use in its metric calculation):

  • MTU (Maximum Transmission Unit)
  • Hop Count

Use show interface command to view the metrics used on a specific interface that is routing EIGRP.

  • These are the raw values.

Rick Graziani graziani@cabrillo.edu

metric calculation38

delay

bandwidth

load

reliability

Metric Calculation

Router> show interfaces s1/0

Serial1/0 is up, line protocol is up

Hardware is QUICC Serial

Description: Out to VERIO

Internet address is 207.21.113.186/30

MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,

rely 255/255, load 246/255

Encapsulation PPP, loopback not set

Keepalive set (10 sec)

<output omitted>

Rick Graziani graziani@cabrillo.edu

metric calculation review
Metric Calculation (Review)
  • k1 for bandwidth
  • k2 for load
  • k3 for delay
  • k4 and k5 for Reliability

Router(config-router)# metric weightstos k1 k2 k3 k4 k5

EIGRP

bandwidth is in kbps

Rick Graziani graziani@cabrillo.edu

slide40

IGRP

Viva la difference!

EIGRP

Calculated values (cumulative) displayed in routing table (show ip route).

EIGRP values are 256 times greater.

Rick Graziani graziani@cabrillo.edu

displaying interface values
Displaying Interface Values

shows reliability as a fraction of 255, for example (higher is better):

rely 190/255 (or 74% reliability)

rely 234/255 (or 92% reliability)

rely 255/255 (or 100% reliability)

Router> show interface s0/0

Serial0/0 is up, line protocol is up

Hardware is QUICC Serial

Description: Out to VERIO

Internet address is 207.21.113.186/30

MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,

rely 255/255, load 246/255

Encapsulation PPP, loopback not set

Keepalive set (10 sec)

<output omitted>

Bandwidth

Delay

Reliability

Load

shows load as a fraction of 255, for example (lower is better):

load 10/255 (or 3% loaded link)

load 40/255 (or 16% loaded link)

load 255/255 (or 100% loaded link)

Rick Graziani graziani@cabrillo.edu

displaying interface values42
Displaying Interface Values

Routing Table Metric

  • Default: Slowest of bandwidth plus the sum of the delays of all outgoing interfaces from “this router” to the destination network.

Router> show interface s0/0

Serial0/0 is up, line protocol is up

Hardware is QUICC Serial

Description: Out to VERIO

Internet address is 207.21.113.186/30

MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,

rely 255/255, load 246/255

Encapsulation PPP, loopback not set

Keepalive set (10 sec)

<output omitted>

Bandwidth

Delay

Reliability

Load

Rick Graziani graziani@cabrillo.edu

metric calculation43
Metric Calculation

Bandwidth

  • Expressed in kilobits (show interface)
  • This is a static number and used for metric calculations only.
  • Does not necessarily reflect the actual bandwidth of the link.
  • It is an information parameter only.
  • You cannot adjust the actual bandwidth on an interface with this command.
  • Use the show interface command to display the raw value

The default values:

  • Default bandwidth of a Cisco interface depends on the type of interface.
  • Default bandwidth of a Cisco serial interface is 1544 kilobits or 1,544,000 bps (T1), whether that interface is attached to a T1 line (1.544 Mbps) or a 56K line.
  • IGRP metric uses the slowest bandwidth of all of the outbound interfaces to the destination network.

Rick Graziani graziani@cabrillo.edu

metric calculation44
Metric Calculation

Changing the bandwidth informational parameter:

The bandwidth can be changed using:

Router(config-if)# bandwidthkilobits

To restore the default value:

Router(config-if)# no bandwidth

Rick Graziani graziani@cabrillo.edu

metric calculation45
Metric Calculation

Delay

  • Like bandwidth, delay it is a static number.
  • Expressed in microseconds, millionths of a second
  • (Uses the Greek letter mu with an S, S, NOT “ms” which is millisecond or thousandths of a second)
  • Use the show interface command to display the raw value
  • It is an information parameter only.

The default values:

  • The default delay value of a Cisco interface depends upon the type of interface.
  • Default delay of a Cisco serial interface is 20,000 microseconds, that of a T1 line.
  • IGRP metric uses the sum of all of the delays of all of the outbound interfaces to the destination network.

Rick Graziani graziani@cabrillo.edu

metric calculation46
Metric Calculation

Changing the delay informational parameter:

The delay can be changed using:

Router(config-if)# delay tens-of- S

(microseconds)

Example of changing the delay on a serial interface to 30,000 microseconds:

Router(config-if)# delay 3000

To restore the 20,000 microsecond default value:

Router(config-if)# no delay

Rick Graziani graziani@cabrillo.edu

metric calculation47
Metric Calculation

IGRP

  • bandwidth = (10,000,000/bandwidth)
  • delay = delay/10

Note: EIGRP

  • bandwidth = (10,000,000/bandwidth) * 256
  • delay = (delay/10) * 256

Note: The reference-bandwidth

For both IGRP and EIGRP: 107, (10,000,000/bandwidth kbps), whereas with OSPF it was 108 (100,000,000/bandwidth)

The difference:

  • IGRP metric is 24 bits long
  • EIGRP metric is 32 bits long
  • EIGRP metric is 256 times greater for the same route
  • EIGRP allows for finer comparison of potential routes

Rick Graziani graziani@cabrillo.edu

slide48

IGRP Metrics

Values displayed in show interface commands and sent in routing updates.

Calculated values (cumulative) displayed in routing table (show ip route). EIGRP values are 256 times greater.

Rick Graziani graziani@cabrillo.edu

metric calculation49

delay

bandwidth

load

reliability

Metric Calculation

Router> show interfaces s1/0

Serial1/0 is up, line protocol is up

Hardware is QUICC Serial

Description: Out to VERIO

Internet address is 207.21.113.186/30

MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,

rely 255/255, load 246/255

Encapsulation PPP, loopback not set

Keepalive set (10 sec)

<output omitted>

Rick Graziani graziani@cabrillo.edu

slide50

From Casablanca to 172.20.40.0/24

Rick Graziani graziani@cabrillo.edu

from casablanca to 172 20 40 0 24
From Casablanca to 172.20.40.0/24

Using BWIGRP and DLYIGRP to calculate the IGRP metric:

The slowest bandwidth has the highest BWIGRP value.

IGRP metric

= highestBWIGRP + total of the DLYIGRP

= 19,531 + (100 + 2,000 + 2,000 + 100)

= 19,531 + 4,200

= 23,731

Rick Graziani graziani@cabrillo.edu

slide53

From Casablanca to 172.20.40.0/24

Rick Graziani graziani@cabrillo.edu

slide54

Calculating Bandwidth

So how is Bandwidth, BWIGRP, calculated?

  • The bandwidth metric is calculated by taking 107 (10,000,000) and dividing itby the slowest bandwidth metric along the route to the destination.
  • This is known as taking the inverse of the bandwidth scaled by a factor of 107 (10,000,000)

The lowest bandwidth on the route is 512K or 512 (measured in kilobits), the outgoing interface of the Quebec router.

Divide 10,000,000 by 512 and you get the bandwidth!

Bandwidth = 10,000,000/512

= 19,531

Which is the lowest BWIGRP along the route

Rick Graziani graziani@cabrillo.edu

slide55

Calculating Delay

So how is Delay, DLYIGRP, calculated?

  • Delay is the total sum of delays on the outgoing interfaces, in 10-microsecond units
  • The sum of the delays on each of the outgoing interfaces between Casablanca and Yalta, from 172.20.1.0/24 through 172.20.40.0/24 is:
  • 1,000 (Casablanca) + 20,000 (Teheran) + 20,000 (Quebec) + 1,000 (Yalta) = 42,000

We need this in 10-microsecond units:

= (1,000/10)+(20,000/10) + (20,000/10) + (1,000/10)

= 100 + 2,000 + 2,000 + 100

or

= (1,000 + 20,000 + 20,000 +1,000) / 10

In either case the total sum is:

Delay = 4,200

Which is the total of the DLYIGRP, the total Delays along the route!

Rick Graziani graziani@cabrillo.edu

slide56

Slowest Bandwidth + Sum of Delays

IGRP metric = Bandwidth + Delay

IGRP metric = 19,531 + 4,200

= 23,731

IF we were using RIP, the RIP metric would be 3 hops.

Rick Graziani graziani@cabrillo.edu

slide57

show ip route 172.20.40.0

Casablanca# show ip route 172.20.40.0

Known via igrp 1, distance 100, metric 23,731

172.20.1.2, from 172.20.1.2 on Ethernet 0

Route metric is 23,731

Total delay is 42,000 microseconds,

minimum bandwidth is 512 Kbit

...

  • Not to be redundant, but if we were using RIP, the RIP metric would be 3 hops.

Rick Graziani graziani@cabrillo.edu

reliability and load
Reliability and Load

The metrics used by EIGRP in making routing decisions are (lower the metric the better):

  • bandwidth
  • delay
  • load
  • reliability

By default, EIGRP uses only:

  • Bandwidth
  • Delay

Rick Graziani graziani@cabrillo.edu

reliability and load60
Reliability and Load

Reliability

  • Reliability is measure dynamically
  • Uses error rate for measurement
  • Reflects the total outgoing error rates of the interfaces along the route
  • Calculated on a five minute weighted average, so not to allow sudden peaks and valleys to make a significant impact

Expressed as an 8 bit number

  • 255 is a 100% reliable link
  • 1 is a minimally reliable link

Higher the better!

Rick Graziani graziani@cabrillo.edu

reliability and load61

delay

bandwidth

load

reliability

Reliability and Load

shows reliability as a fraction of 255, for example:

rely 190/255 (or 74% reliability)

rely 234/255 (or 92% reliability)

rely 255/255 (or 100% reliability)

Router> show interfaces s1/0

Serial1/0 is up, line protocol is up

Hardware is QUICC Serial

Description: Out to VERIO

Internet address is 207.21.113.186/30

MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,

rely 255/255, load 246/255

Encapsulation PPP, loopback not set

Keepalive set (10 sec)

<output omitted>

Rick Graziani graziani@cabrillo.edu

reliability and load62
Reliability and Load

Load

  • Load is measure dynamically
  • Uses channel occupancy for measurement
  • Reflects the total outgoing load of the interfaces along the route
  • Calculated on a five minute weighted average, so not to allow sudden peaks and valleys to make a significant impact

Expressed as an 8 bit number

  • 255 is a 100% loaded link
  • 1 is a minimally loaded link

Lower the better!

Note: Even though load and reliability are dynamically changing values, EIGRP will not recalculate the route metric when these parameters change.

Rick Graziani graziani@cabrillo.edu

reliability and load63

delay

bandwidth

load

reliability

Reliability and Load

shows load as a fraction of 255, for example:

load 10/255 (or 3% loaded link)

load 40/255 (or 16% loaded link)

load 255/255 (or 100% loaded link)

Router> show interfaces s1/0

Serial1/0 is up, line protocol is up

Hardware is QUICC Serial

Description: Out to VERIO

Internet address is 207.21.113.186/30

MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,

rely 255/255, load 246/255

Encapsulation PPP, loopback not set

Keepalive set (10 sec)

<output omitted>

Rick Graziani graziani@cabrillo.edu

reliability and load64
Reliability and Load

IGRP metric =

[k1* BWIGRP(minimum) +

(k2* BWIGRP(minimum))/(256-LOAD) +

k3* DLYIGRP(sum) ] *

[k5/RELIABILITY + k4)]

  • k2 metric effects LOAD
  • k4 and k5 effects RELIABILITY
  • Multiply Reliability only if > 0

Default:

k1=k3=1 and k2=k4=k5=0

  • You may change the k values to change what you want to give more or less weight to.
    • k1 for bandwidth
    • k2 for load
    • k3 for delay
    • k4 and k5 for Reliability
  • Higher the k value, the more that part of the metric is used to calculate the overall IGRP metric

Rick Graziani graziani@cabrillo.edu

reliability and load65
Reliability and Load

Turning the knobs:

We can use the other metrics of Reliability and Load by adjusting their k values to something greater than “0”

The command to adjust the k values is:

Router(config-router)# metric weightstos k1 k2 k3 k4 k5

Notes:

  • tos is always set to 0; at one time it was Cisco’s intent to use it, but it was never implemented
  • EIGRP neighbors must agree on K values to establish an adjacency and to avoid routing loops.

Caution!

  • Know what the impact will be before changing the defaults.
  • It can give you unexpected results if you do not know what you are doing!
  • If you modify the weights, you should configure all routers so they are all using the same weight values.

Rick Graziani graziani@cabrillo.edu

igrp and eigrp a migration path
IGRP and EIGRP: A migration path

Rick Graziani graziani@cabrillo.edu

ch 7 distance vector routing protocols part 2 of 2 distance vector routing and igrp67

Ch. 7 – Distance Vector Routing ProtocolsPart 2 of 2: Distance Vector Routing and IGRP

CCNA version 1.0

Rick Graziani

Cabrillo College