[162298] in North American Network Operators' Group
Re: Verizon DSL moving to CGN
daemon@ATHENA.MIT.EDU (Rajiv Asati (rajiva))
Mon Apr 8 15:36:15 2013
From: "Rajiv Asati (rajiva)" <rajiva@cisco.com>
To: Tore Anderson <tore@fud.no>, Mikael Abrahamsson <swmike@swm.pp.se>,
"nanog list" <nanog@nanog.org>
Date: Mon, 8 Apr 2013 19:36:03 +0000
In-Reply-To: <5162B623.5030301@fud.no>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Tore,
> 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
Yes, indeed.=20
In fact, almost all of the MAP CE implementations (that I am aware of) are
open source/linux based -
http://enog.jp/~masakazu/vyatta/map/
http://mapt.ivi2.org:8039/readme.txt
Cheers,
Rajiv
-----Original Message-----
From: Tore Anderson <tore@fud.no>
Date: Monday, April 8, 2013 8:20 AM
To: Mikael Abrahamsson <swmike@swm.pp.se>, nanog list <nanog@nanog.org>
Cc: Rajiv Asati <rajiva@cisco.com>
Subject: Re: Verizon DSL moving to CGN
>* 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
