> Yes, one particular plotline which can explain why docsis systems do > this is that standard residential customers are provisioned using > giant broadcast domains directly on the cable, with DHCP config. > Obviously it's more complicated because it's docsis, but lemme > handwave and say that this is the gist of it. Because you're dealing > with giant broadcast domains, you assign IP address blocks to > individual CMTSs and your customers are assigned out of those ranges. > > Assigning ipv6 in this context is really simple: it's part of the > baseline DOCSIS3.0 standard and is supported incredibly well by all > parts of the network. > > Static addresses don't fit into this paradigm because you if you > configure your static customers from a single broadcast domain, then > they are glued to a particular CMTS and can't be moved from that CMTS > unless you renumber them. > > This doesn't work in practice because if you want to grow your > network, you probably want to be able to move around chunks of your > cable network from one CMTS to another in order to balance out your > traffic. Or you might want to split a bunch of cable nodes from one > CMTS to multiple, according as your traffic outgrew the capabilities > of a single CMTS (a node in this context is a small chunk of a cable > network). > > One way of getting around this mess is to backhaul all your static > customer interfaces using mpls l2vpn PWHE up to a L3 box which just > handles static IP addresses. You configure the customer's static > default gateway IP address on an interface on this head-end router, > and the customer's cable modem will have a virtual connection directly > to that interface. The thing is, this virtual interface termination > system might or might not be tied into the entire ipv6 provisioning > system. If it isn't, you're SoL. So even if dirt-cheap residential > customers can get ipv6 very easily, it's different by virtue of the > fact that you're using static IP addresses, because they're a headache > for cable operators.
aha! makes sense. i'll settle for dynamic. if i need static internally, i can always do nat66 :)/2 i do not want to play how hard can we make ipv6 deployment; just want to enable it on a five-segment office lan. but i am beginning to see that there may be a reason i am having problems getting past an account rep. randy
