Re: EIGRP Metrics

Very well put Scott. Agreed.

On Tue, Aug 25, 2009 at 4:09 PM, Scott Morris <smorris_at_ine.com> wrote:

> Looking at:
>
> (some random number) divided by (the link's reliability value + some
> different random number)
>
> Just how is it that it has anything to do with MTU?
>
> If you are entering the metric on a command line, yes, the FIFTH value is
> the mtu. Those are seeds for the route. Yes, MTU is carried to determine
> the lowest MTU along a path for tie breakers, but in the math presented
> there, the "K5" value has nothing to do with MTU.
>
> I'd actually argue that the docs have things wrong (listing K4 as
> reliability and K5 as a modifier) since mathematically 0/(any number) = 0,
> so K5 would really be the on/off switch while K4 would just be an additive
> value due to the + sign and not a * sign in the algorithm.
>
> But that's just me looking for math to make sense. ;)
>
> I'm open to other thoughts though as it's not a widely explored topic, but
> math is generally straightforward. At least with the values presented in
> the equation!
>
>
>
>
> *Scott Morris*, CCIE*x4* (R&S/ISP-Dial/Security/Service Provider) #4713,
>
> JNCIE-M #153, JNCIS-ER, CISSP, et al.
>
> JNCI-M, JNCI-ER
>
> evil_at_ine.com
>
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>
>
> Joe Astorino wrote:
>
> K5 is MTU. In the formula to calculate the metric it is written as metric =
> [K1*bandwidth + (K2*bandwidth)/(256 - load) + K3*delay] * [K5/(reliability +
> K4)] ... but K5 still represents the MTU
>
> On Tue, Aug 25, 2009 at 3:06 PM, Cisco Fanatic <ebay_products_at_hotmail.com> <ebay_products_at_hotmail.com>wrote:
>
>
>
> All,
>
> It is simple, but somehow I get confused with different wording in
> different
> docs.
>
> Is K5 MTU or (K4 and K5 both reliability)?
>
>
>
>
>
> ToS - 0
>
> Bandwidth - K1
>
> Load - K2
>
> Delay - K3
>
> Reliability - K4
>
>
> MTU - K5
>
> -Yuri
>
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-- 
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Joe Astorino - CCIE #24347 R&S
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