> Single mode fiber's usefulness doesn't expire within any funding > horizon applicable to a municipality. Gige service and any other lit > service you can come up with today does.
Well, not in the foreseeable future, anyway. I'm sure there was a time when that claim could have been made about copper. I would not make that claim about copper today (or even 10 years ago). >> I can also see how some longer-distance links, imagine a link from >> home to office across 30-40 miles, might be cheaper to deliver as 100M >> VLAN than raw dark fiber and having to buy long reach optics. > > Long-reach optics are relatively cheap, or at least they can be if you > optimize for expense. The better example is when you want ISP #1, > phone company #2, TV service #3, data warehouse service #4, etc. With > a lit service, you only have to buy the last-mile component once. In such a case, is there a reason you couldn't use the optics from ISP#1 as lit service to reach PhoneCo #2, TV-Co #3, and Warehouse #4 if that was desirable? Surely at least one of the 4 could provide optics and a convenient layer 2 handoff for the other services at least as easily and cost-effectively as L2 service from the L1 fiber provider. >> 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. If it consumes electricity, regardless of power source, it shouldn't be part of the facilities network provider's purview with the possible exception of technology-agnostic amplifiers, which should be avoided whenever possible. > 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. Even ULA would be a better (albeit nearly as bad) choice than RFC-1918. Hmmm... Can one run 802.1q over GRE? (Too lazy to look that one up at the moment). Owen
