Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!csn!boulder!daemon
From: Allen Robel <robel2@mythos.ucs.indiana.edu>
Newsgroups: comp.dcom.sys.cisco
Subject: Re: delay of an interface
Message-ID: <33623@boulder.Colorado.EDU>
Date: 25 Mar 91 20:10:29 GMT
Sender: daemon@boulder.Colorado.EDU
Lines: 43

>       metric = [K1*bandwidth + (K2*bandwidth)/(256 - load) + K3*delay] *
>                                                [(reliability + K4)/K5]
>
>       If K5 == 0, then there is no reliability term.
>       The default version of IGRP has K1 == K3 == 1, K2 == K3 == K5 == 0"


With K5=0 you're dividing by zero which is a no-no, right?  Is K5 

really equal 0 or is the equation wrong?  I'd like to include the 

metric in the IGRP decoder I'm working on for Network General's Sniffer.

I checked in Hedrick's paper @ ftp.cisco.com ~ftp/igrp.ps and the above
is an accurate representation as it appears in that paper.

>The Bandwidth must be inverted and scaled by 10E10.  Also quoting from
>the same source:
>
>"Bandwidth is inverse bandwidth in bits per sec scaled by a factor of
>10e10.  The range is from a 1200 bps line to 10 Gbps....  


I tried this on my trusty HP:

(1/6476)*10E10 (for T1 bandwidth = 1.544Mbs)

and get:

15,441,630.6362

My guess is that this should be 10E9?

Any info from anyone clarifying these points would be most helpful!

thanks,

Allen Robel                            robel2@mythos.ucs.indiana.edu 

University Computing Services          ROBELR@IUJADE.BITNET 

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