Re: OSPF Sham links in real life

Tyson,
There's no doubt that customers and providers use area 0, Jack mentioned
that they see IA routes because LSAs get converted to type 3 by PE routers
(lack of sham-links for proper OSPF flooding - natural behavior). So he's
asking why providers do not use Sham-links...

I say they are lazy!

-- 
-- 
Sincerely,
Shawn Zandi
Network Architect and Consultant
Cisco Certified CCIE x2 (R&S + Security)
Juniper JNCIS x2 (ER & SEC) - Foundry/Brocade BCNE - Procurve Master ASE
(MASE)
Dubai Internet City
web: http://www.shafagh.com
blog: http://blog.shafagh.com
email: shafagh_at_shafagh.com
On Wed, Sep 8, 2010 at 5:29 PM, Tyson Scott <tscott_at_ipexpert.com> wrote:
> For the providers that run it to the edge the comments from students that I
> have had that actually do it they say area 0 is always extended to the
> provider.  They had never allowed a customer to connect with anything
> except
> Area 0.
>
> Regards,
>
> Tyson Scott - CCIE #13513 R&S, Security, and SP
> Managing Partner / Sr. Instructor - IPexpert, Inc.
> Mailto: tscott_at_ipexpert.com
>
>
> -----Original Message-----
> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
> Jack
> Router
> Sent: Tuesday, September 07, 2010 4:27 PM
> To: 'Cisco certification'
> Subject: OSPF Sham links in real life
>
> In my workbooks sham-links are presented as a way of tricking the router to
> send traffic via MPLS cloud and not via the backup link, when OSPF is
> redistributed via MBGP.
> My question is:
> On real networks, is it practical to configure sham links even if no backup
> links are installed? The reason for this would be to avoid confusion with O
> and IA routes, so routes originated in the same area are seen as internal
> routes O and not inter-area IA.
>
> thx
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