Re: Poison-reverse

In *RIP *both Split Horizon and Poison reverse are ON by default under the
RIP process, and i dont know if there exist a command to turn the Poison
reverse OFF

When talking about *RIPng*, Split Horizon is ON by default whereas Poison
reverse is OFF.
We could call this a flexible implementation.

The combination of the above helps in tackling routing loops efficiently
though Poison reverse will create overhead in routing updates.(think
bandwidth)

I would still Request for more comments on this..-:)

On Mon, Aug 17, 2009 at 11:07 PM, Anantha Subramanian Natarajan <
anantha.natarajan_at_gravitant.com> wrote:

> Hi Pramod,
>
> Thanks for the detailed explanation.Is that mean,poison reverse is inbuild
> on the routing protocol when it is configured and there wouldn't be
> provision to enable or disable it ?.My basic curiousness for this question
> arrived from seeing a "poison-reverse"command under ipv6rip.I am wondering,
> is there a command related to poison-reverse on IPV4 distance vector
> routing
> protocol.
>
> Thanks
>
> Regards
> Anantha Subramanian Natarajan
>
> On Mon, Aug 17, 2009 at 3:57 PM, Pramod G <learn02earn_at_gmail.com> wrote:
>
> > Split horizon refers to the rule that information about a route will not
> be
> > sent out the same
> > interface or subinterface from which it was received (problem in
> multipoint
> > configurations)
> >
> > no ip split-horizon for RIP networks
> > no ip split-horizon as# for EIGRP networks
> >
> > Poison reverse The rule for poison reverse is to advertise a route out
> the
> > interface on
> > which it was received with an unreachable metric. Different routing
> > protocols employ this
> > rule at different times to control routing loops.
> >
> > The router sends a poison reverse update to remove a route and place
> > it in holddown. This is done to avoid a routing loop
> >
> > On Mon, Aug 17, 2009 at 4:16 PM, Abraham, Tharak <
> tharakabraham_at_gmail.com
> > > wrote:
> >
> >> Anantha,
> >>
> >> Distance vector protocols are/should be implemented with split horizon
> and
> >> poison reverse !
> >> Both are different concepts, but gives the best when it works together.
> >>
> >> Please refer to Jeff Doyle Vol 1, read through pages 89 and 90 (pdf)
> with
> >> the examples.
> >>
> >>
> >> Best Regards,
> >> Tharak Abraham
> >>
> >>
> >>
> >> On Mon, Aug 17, 2009 at 9:27 PM, Anantha Subramanian Natarajan <
> >> anantha.natarajan_at_gravitant.com> wrote:
> >>
> >> > Hi All,
> >> >
> >> > I have a question on poison-reverse,to activate or de-activate poison
> >> > reverse for a distance vector routing protocols in cisco router,do we
> >> have
> >> > a
> >> > specific command for the same.Otherwise it is enabled,when we enable
> >> > split-horizon or it is enabled by default for all distance vector
> >> routing
> >> > protocol.I am sure missing something totally basic.Kindly help me to
> >> > understand the same.
> >> >
> >> > Thanks
> >> >
> >> > Regards
> >> > Anantha Subramanian Natarajan
> >> >
> >> >
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Received on Tue Aug 18 2009 - 13:22:37 ART