From: Tarun Pahuja (pahujat@gmail.com)
Date: Thu Oct 25 2007 - 07:26:17 ART
The word "Bandwidth" in my previous Post refers to the actual
bandwidth of the interface and not the configured bandwidth of the
interface. Configured bandwidth will be used by eigrp to calculate
metric and percentage bandwidth it would use for routing updates,
where as the total bandwidth would include all traffic(routing +
data,control) traffic.
Tarun
On 10/25/07, Sachin Bhatia <sachin.bhatia21@gmail.com> wrote:
> For the first query:
>
> What is meant here is that the though the actual bandwidth for the link is
> 56k, EIGRP is made to belive that bandwidth is 25k and coz by default EIGRP
> would use 50% of what is stated in the 'bandwidth' command, here it wud
> default to 12.5K which may not be optimal. So 'bandwidth-percent' tells
> EIGRP to use 90% of the stated bandwidth all the time, congestion or not coz
> ff EIGRP used 50% in normal scenario then 50% of 56K*10VCs=280K which would
> again oversubscribe the hub which has a capacity of 256K only.
>
> User traffic is not affected by the configured bandwidth and would be able
> to utilize the actual bandwidth of the interface.
>
> HTH,
> Sachin
>
>
>
> On 10/25/07, Tarun Pahuja <pahujat@gmail.com> wrote:
> >
> > Ananth,
> > The answer to your second query is as follows:
> >
> > The formula you are referring to was derived from the assumption that
> > their are 10 Virtual circuits with a capacity of 256K hence
> > (256/10),and the .9 is coming from the configuration where 90% of the
> > total bandwidth is configured to be used per interface for EIGRP
> > updates.
> >
> > As Per the First Query:
> > The bandwidth would be shared amongst data and routing updates. In an
> > event of congestion eigrp will be allowed to use 22.5Kbps of
> > bandwidth. By default it uses up to 50% of interface bandwidth.
> >
> > HTH,
> > Tarun
> >
> >
> > On 10/25/07, Ananth Vk <ananth.vk@tcs.com> wrote:
> > > Hi All,
> > >
> > > I need a small clarification on eigrp ip bandwidth-percent command
> > > Following is the link and im pasting the extract from this link below..
> > >
> > >
> http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094063.shtm
> > > l
> > >
> > > ------------------------------------
> > > interface Serial 0.1 point-to-point
> > > bandwidth 25
> > > ip bandwidth-percent eigrp 123 90
> > >
> > > Note that EIGRP will not use more than 22.5Kbps (90% of 25K) on this
> > > interface, even though its
> > >
> > > capacity is 56Kbps. This configuration will not affect user data
> capacity,
> > > which will still be able to use
> > >
> > > the entire 56Kbps.
> > >
> > > Query
> > > 1.If EIGRP uses 22.5Kbps out of 56Kbps howcome the entire 56Kbps can be
> > > used for data traffic
> > > 2.Is BW for data not dependent on BW used for EIGRP updates ?
> > >
> > > If im right this whole concept is only to have a control on % of BW for
> > > updates.
> > > Shouldnt we have less BW for routing updates and more for data ?
> > > But i wonder why by default EIGRP will use 50% of default BW
> > >
> > >
> -----------------------------------------------------------------------------------
> > > Alternatively, if you want to set the interface bandwidth to reflect the
> > > PVC capacity, you can adjust the
> > >
> > > bandwidth percentage for EIGRP. In this example, the desired bandwidth
> for
> > > EIGRP is (256K/10)*.9 =
> > >
> > > 23.04K; the bandwidth percentage would be 23.04K/56K = .41 (41%). So the
> > > same effect would be
> > >
> > > had by configuring:
> > >
> > > interface Serial 0.1 point-to-point
> > > bandwidth 56
> > > ip bandwidth-percent eigrp 123 41
> > >
> > > 1. In this example im not sure why PVC capacity was desired to be
> > > 23K....and what's that 0.9 for, im a bit confused..
> > >
> ---------------------------------------------------------------------------------------
> > >
> > > Thanks
> > > Ananth
> > > =====-----=====-----=====
> > > Notice: The information contained in this e-mail
> > > message and/or attachments to it may contain
> > > confidential or privileged information. If you are
> > > not the intended recipient, any dissemination, use,
> > > review, distribution, printing or copying of the
> > > information contained in this e-mail message
> > > and/or attachments to it are strictly prohibited. If
> > > you have received this communication in error,
> > > please notify us by reply e-mail or telephone and
> > > immediately and permanently delete the message
> > > and any attachments. Thank you
> > >
> > >
> _______________________________________________________________________
> > > Subscription information may be found at:
> > > http://www.groupstudy.com/list/CCIELab.html
> >
> >
> _______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
This archive was generated by hypermail 2.1.4 : Fri Nov 16 2007 - 13:11:18 ART