Re: OSPF vs IS-IS

[Tomas Lynch <tomas.lynch () gmail com>]

On Thu, Aug 11, 2011 at 11:04 AM, Justin M. Streiner <
streiner () cluebyfour org> wrote:

> On Thu, 11 Aug 2011, jim deleskie wrote:
>
>  Having run both on some good sized networks, I can tell you to run
> > what your ops folks know best.  We can debate all day the technical
> > merits of one v another, but end of day, it always comes down to your
> > most jr ops eng having to make a change at 2 am, you need to design
> > for this case, if your using OSPF today and they know OSPF I'd say
> > stick with it to reduce the chance of things blowing up at 2am when
> > someone tries to 'fix' something else.
>
> Agreed.  I did an OSPFv3 vs. IS-IS bake-off in my lab several months ago as
> part of an IPv6 rollout, and one of the key deciding factors in going with
> OSPFv3 over IS-IS was that our ops folks are much more familiar with OSPFv2.
>  While there are difference between OSPFv2 and OSPFv3 in how they work, the
> learning curve is a lot less steep than going from OSPFv2 to IS-IS.
>
> jms
>
> Do not underestimate the power of ops engineers. Really is not that
difficult to learn ISIS and they can add it to their resume.


>  On Thu, Aug 11, 2011 at 10:29 AM, William Cooper <wcooper02 () gmail com>
> > wrote:
> >
> > > I'm totally in concurrence with Stephan's point.
> > >
> > > Couple of things to consider: a) deciding to migrate to either ISIS or
> > > OSPFv3 from another protocol is still migrating to a new protocol
> > > and b) even in the case of migrating to OSPFv3, there are fairly
> > > significant changes in behavior from OSPFv2 to be aware of (most
> > > notably
> > > authentication, but that's fodder for another conversation).
> > >
> > > -Tony
> > >
> > > On Thu, Aug 11, 2011 at 9:06 AM, Stefan Fouant
> > > <sfouant () shortestpathfirst net**> wrote:
> > >
> > > > Well up until not too long ago, to support IPv6 you would run OSPFv3 and
> > > > for IPv4 you would run OSPFv2, making IS-IS more attractive, but that is no
> > > > longer the case with support for IPv4 NLRI in OSPFv3.
> > > >
> > > > The only reason in my opinion to run IS-IS rather than OSPF today is due
> > > > to the fact that IS-IS is decoupled from IP making it less vulnerable to
> > > > attacks.
> > > >
> > > > Stefan Fouant
> > > > JNCIE-M, JNCIE-ER, JNCIE-SEC, JNCI
> > > > Technical Trainer, Juniper Networks
> > > > http://www.shortestpathfirst.**net <http://www.shortestpathfirst.net>
> > > > http://www.twitter.com/sfouant
> > > >
> > > > Sent from my iPad
> > > >
> > > > On Aug 11, 2011, at 8:57 AM, CJ <cjinfantino () gmail com> wrote:
> > > >
> > > >  Hey all,
> > > > > Is there any reason to run IS-IS over OSPF in the SP core? Currently,
> > > > > we
> > > > > are running IS-IS but we are redesigning our core and now would be a
> > > > > good
> > > > > time to switch. I would like to switch to OSPF, mostly because of
> > > > > familiarity with OSPF over IS-IS.
> > > > > What does everyone think?
> > > > >
> > > > > --
> > > > > CJ
> > > > >
> > > > > http://convergingontheedge.com <http://www.**convergingontheedge.com<http://www.convergingontheedge.com>
> > > > > >