Transit LAN vs. Individual LANs

Scott Weeks surfer at
Mon Feb 27 18:47:32 UTC 2006

> --On February 25, 2006 11:04:12 AM -0500 "Patrick W.
> Gilmore" <patrick at> wrote:
> > On Feb 24, 2006, at 9:03 PM, Scott Weeks wrote:
> > 
> >> I have 2 core routers (CR) and 3 access routers (AR)
> >> currently connected point-to-point where each AR
> connects to >> each CR for a total of 6 ckts.  Now someone
> has decided to >> connect them with Gig-E.  I was
> wondering about the benefits >> or disadvantages of
> keeping the ckts each in their own >> individual LANs or
> tying them all into one VLAN for a >> "Transit LAN" as
> those folks that decided on going to Gig-E >> aren't doing
> any logical network architecting (is that a >> real
> word?).
> In my experience either solution has tradeoffs and the
> correct one depends greatly on your traffic patterns. 
> Having said that, what I find causes most of the problems
> in either solution is when the Layer 3 topology starts to
> diverge from the Layer 2 topology.

Hi Guys,

Apologies for the late response, I had to do an unexpected
outer island trip and got back late last night.

I am just using OSPF area zero between the CRs and ARs.  So,
it's full mesh over a LAN if I do the "transit LAN".  Is
that what you're referring to?  Could you elaborate?


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