[89007] in North American Network Operators' Group
Re: Transit LAN vs. Individual LANs
daemon@ATHENA.MIT.EDU (Stephen Sprunk)
Tue Feb 28 20:24:22 2006
From: "Stephen Sprunk" <stephen@sprunk.org>
To: "Ejay Hire" <ejay.hire@isdn.net>
Cc: "North American Noise and Off-topic Gripes" <nanog@merit.edu>
Date: Mon, 27 Feb 2006 13:29:25 -0600
Errors-To: owner-nanog@merit.edu
Thus spake "Ejay Hire" <ejay.hire@isdn.net>
>From my perspective...
> ...a physical mesh requires too many ports to be economical.
But, if one has the money, it's probably the better technical choice. Since
his folks are already familiar with having things set up PTP using some
other physical layer, that also reduces the odds of human error.
> ...a logical mesh has a couple of things against it. It
> requires a lot of configuration, and each router will be
> connected with a trunk interface, (on the antique switches
> I've worked with) every trunk will carry all the traffic in
> the switch, your maximum bandwidth across the whole switch
> is 1gbps, instead of the next option which gives you more
> bandwidth across the switch.
Not true, unless you're using some antique switching gear. Assuming all
traffic is up/downstream and not sideways, you can get 4Gb/s in each
direction (two CRs connected to two switches each). Whether you break that
into PTP VLANs or shared VLANs shouldn't affect anything.
[ Note that this is moot since the OP responded he's running a physical
mesh ]
S
Stephen Sprunk "Stupid people surround themselves with smart
CCIE #3723 people. Smart people surround themselves with
K5SSS smart people who disagree with them." --Aaron Sorkin