Circuit numbering scheme - best practice?
Justin M. Streiner
streiner at cluebyfour.org
Sat Jan 17 00:10:28 UTC 2009
On Fri, 16 Jan 2009, Jay Hennigan wrote:
> Any suggestions from those who have been down this road as to a schema that
> makes sense and is scalable? Are there documented best practices?
Many of the RBOCs (if they can be called that anymore) use the Common
Language Circuit Identifier (CLCI) nomenclature for identifying circuits.
Many large carriers, especially those that have spent more time buying up
competitors then integrating previous acquisitions' provisioning systems,
have a mish-mash of different circuit numbering schemes, depending on
whose underlying plant and provisioning systems were used to build the
circuit in the first place.
Like you, I have seen everything from telcos that just use a number and
not much else, to telcos that try to tell someone's life story in the form
of a circuit ID, to forms that are somewhere in between. I won't say one
is better than another, but I do favor shorter ones, if for no other
reason than they're easier to key into provisioning systems, interface
desciptions and put on wire labels :)
I also got into the habit a long time ago of recording every circuit ID
for a particular circuit. Many of the circuit I dealt with were long-haul
circuits, or were provisioned by a LEC and had to be handed off to an
incumbent carrier for final delivery to the customer, and one particular
LEC burned me several times by stating, "Oh, I see we hand that off to
$TELCO... I don't have a circuit ID for that piece....".
Since you have the luxury of starting from scratch, you have the option of
creating a system that best fits your needs. If you have or can build a
provisioning system that captures all of the information you need, then
you can get away with a simpler ID, such as a plain number. The
information you want to capture would depend on the type of circuit, but
would generally include things like carrier/customer handoff points,
router interface/switch ports, VLANs, MPLS labels, patch assignments,
etc...
It's also a good idea to come up with a standard format for identifying
your facilities/rooms/racks if you haven't already. Many providers use
Common Language Location Identifier (CLLI) codes for this, which is
another telco hold-over, but you can ID them however you want, as long as
it makes sense to you and scales as you grow your network.
jms
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