Muni Fiber and Politics

William Herrin bill at
Mon Aug 4 17:27:48 UTC 2014

On Mon, Aug 4, 2014 at 12:35 PM, Owen DeLong <owen at> wrote:
>>> I can never see a case where letting them play at Layer 3 or above helps.
>> Layers 2 and 3 are fuzzy these days. I think that's a bad place to draw a line.
>> Rather draw the line between providing a local interconnect versus
>> providing services and out-system communications.
> I think the best line to draw is between passive facilities and active components.

Hi Owen,

You've convinced me. However, I think it's still worth talking about
where you draw the second line -- if the infrastructure provider
implements a network with active components and some kind of digital
data passing protocol, what should the scope of that capability be
limited to?

>> With a multi-service provider network there are, IMO, major advantages
>> to implementing it with private-IP IPv4 instead of a layer 2 solution.
>> No complicated vlans, PPoE or gpon channels. Just normal IP routing
>> and normal access control filters available in even the cheap
>> equipment. Then run your various virtual wire technologies (e.g. VPNs)
>> over the IP network. Everybody is a peer on the network, so the
>> infrastructure provider doesn't need to know anything about
>> customer-service provider relationships and doesn't need to implement
>> any special configurations in their network to serve them.
> In an already-sunk equipment cost environment, this might be a
> necessary tradeoff. In a greenfield deployment, there's no reason
> whatsoever not to use IPv6 GUA in place of RFC-1918 with the
> added advantage that you are not limited to ~17 million managed
> entries per management domain.

Cost and availability of tools, equipment and personnel still strongly
favors IPv4. Presumably that will eventually change, but it won't
change for the equipment you can purchase today. The only point of
providing lit service is to suppress the initial consumer-level cost,
so let's not suggest choices that increase it.

If the local infrastructure provider has a million customers in a
single domain, it is too large to have implemented itself
cost-effectively (they'll be using the super-expensive high-capacity
low-production-run core equipment) and is straying into that
undesirable territory where the infrastructure provider becomes a
general service provider.

Bill Herrin

William Herrin ................ herrin at  bill at
Owner, Dirtside Systems ......... Web: <>
Can I solve your unusual networking challenges?

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