Is bandwidth and clock rate needed on a PPP connection

Question.

/*****************?
en
config t
username test password letmein
int s0
encap ppp
ppp authn chap
ip address x.x.x.x 255.255.255.0
no shut
/*************/

is the bandwidth and clock rate command needed? cisco and Todd do not mention anythnig about it in their books, so it is just a question if needed when configuring. If i think this out, i would say no, because IGRP and EGIRP use bandwith to determine path, and the nature of ppp will not forward this protocol out the interface, am i right to assume this, or am i totally off?

thank you.

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Comments

Netstudent

bandwidth is arbitrary and only for routing protocol calculations. The clock rate would be needed for any DCE interface. Doesn't matter what encapsulation you have.

datchcha

Netstudent wrote:

bandwidth is arbitrary and only for routing protocol calculations. The clock rate would be needed for any DCE interface. Doesn't matter what encapsulation you have.

so is it a wise idea just to supply the commands and details on the interface any way?

datchcha

datchcha wrote:

Netstudent wrote:

bandwidth is arbitrary and only for routing protocol calculations. The clock rate would be needed for any DCE interface. Doesn't matter what encapsulation you have.

so is it a wise idea just to supply the commands and details on the interface any way?

Because i noticed through out Todd's book he supplies the clock rate, and notes that it is not needed, he just likes to supply it.

Stotic

I always apply a clock rate on my DCE, but rarely do I use the bandwidth command because it is only used to manipulate a routing protocol.

Netstudent

Ya when using routing protocols that use cost or bandwidth, it is best to nail down the bandwidth to the correct values so that traffic takes the correct path. If the bandwidth is left to a default value, the traffic could take a less optimal path. For home lab purposes I don;t think it is that imporant. In large production networks it is probably very important. With OSPF in homelabs I like to change the bandwidth just to see the SPF algorithm change to a shorter path.
Just to watch ospf topology database behavior, and new routes.

datchcha

Great help - answered my crazy brain storm...thank you.

keenon

you could use the bandwidth statement if you wanted the interface to transmit at a speed slower than it has..

for example on the T1 =1544 but you only have a cir 512