nanog mailing list archives
Re: Verizon DSL moving to CGN
From: Tore Anderson <tore () fud no>
Date: Mon, 08 Apr 2013 14:20:51 +0200
* Tore Anderson
The tunnel endpoint will 99.99% of cases be a CPE with a NAPT44 component though, so there is some NAT involved in the overall solution, but it's pretty much the same as what we have in today's CPEs/HGWs. The only significant difference is that a MAP CPE must be prepared to not being able to use all the 65536 source ports.
BTW. It is AIUI quite possible with MAP to provision a "whole" IPv4 address or even a prefix to the subscriber, thus also taking away the need for [srcport-restricted] NAPT44 in the CPE. I find that the easiest way to visualise MAP is to take the 16 bits of TCP/UDP port space, and bolt it onto the end of the 32 bits of the IPv4 address space, for a total of 48 "routable" bits. So while the primary use case for MAP is to provision less than 32 bits to the individual customers (say a "/34" -> 4 subscribers per IPv4 address w/16k ports each), you can also give out a "whole" /32 or a /24 or whatever - perhaps only to the customers that are willing to pay for the privilege. I haven't tested, but I believe that if you were to hook up a standard Linux box to a ISP that provides /32 or shorter over MAP, you don't really need any special MAP support in the IP stack to make it go - you'd have to calculate the addresses to be used yourself, but once you've got them, you could just configure everything using standard "ip tunnel/address" commands. It's quite neat, I think. :-) Tore
Current thread:
- Re: Verizon DSL moving to CGN, (continued)
- Re: Verizon DSL moving to CGN Rajiv Asati (rajiva) (Apr 07)
- Re: Verizon DSL moving to CGN Sam Hayes Merritt, III (Apr 07)
- Re: Verizon DSL moving to CGN Rajiv Asati (rajiva) (Apr 08)
- Re: Verizon DSL moving to CGN Mikael Abrahamsson (Apr 08)
- Re: Verizon DSL moving to CGN Tore Anderson (Apr 08)
- Re: Verizon DSL moving to CGN Mikael Abrahamsson (Apr 08)
- Re: Verizon DSL moving to CGN Tore Anderson (Apr 08)
- Re: Verizon DSL moving to CGN Tore Anderson (Apr 08)
- Re: Verizon DSL moving to CGN Mikael Abrahamsson (Apr 08)
- Re: Verizon DSL moving to CGN Randy Bush (Apr 08)
- Re: Verizon DSL moving to CGN Tore Anderson (Apr 08)
- Re: Verizon DSL moving to CGN Jack Bates (Apr 08)
- Re: Verizon DSL moving to CGN joel jaeggli (Apr 08)
- Re: Verizon DSL moving to CGN Jack Bates (Apr 08)
- Re: Verizon DSL moving to CGN Owen DeLong (Apr 08)
- Re: Verizon DSL moving to CGN Shishio Tsuchiya (Apr 08)
- Re: Verizon DSL moving to CGN Rajiv Asati (rajiva) (Apr 08)
- Re: Verizon DSL moving to CGN Rajiv Asati (rajiva) (Apr 08)
- Re: Verizon DSL moving to CGN Rajiv Asati (rajiva) (Apr 08)
- Re: Verizon DSL moving to CGN Rajiv Asati (rajiva) (Apr 08)
- Re: Verizon DSL moving to CGN Christopher Morrow (Apr 08)