Cogent IPv6

William Herrin bill at
Thu Jun 9 15:02:26 UTC 2011

On Thu, Jun 9, 2011 at 10:02 AM, Jack Bates <jbates at> wrote:
> Some networks prefer a uniform numbering scheme. /112 allows for reasonable
> addressing needs on a circuit. In addition, while Ethernet is often used in
> a point-to-point access circuit, such layouts may change and renumbering
> would be annoying.
> Finally, having chunks 4-7 define the circuit and chunk 8 provide the
> circuit addressing makes it more human readable and is prone to less
> mistakes by those who suck at math.

Hi Jack,

I follow the reasoning, but unless you attach undue importance to the
colons you get basically the same result with a /124.

I guess choosing /112 for a point to point link is one of the weird
side-effects of placing :'s in the address at fixed locations instead
of arbitrary locations that serve the writer's mnemonic convenience.

Bill Herrin

William D. Herrin ................ herrin at  bill at
3005 Crane Dr. ...................... Web: <>
Falls Church, VA 22042-3004

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