Transit LAN vs. Individual LANs

Stephen Sprunk stephen at
Mon Feb 27 19:29:25 UTC 2006

Thus spake "Ejay Hire" <ejay.hire at>
>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 ]


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 

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