MAP-E

Fri Aug 9 17:10:43 UTC 2019

On 8/8/19 9:00 PM, Masataka Ohta wrote:
> Lee Howard wrote:
>
>> MAP-T, MAP-E. IPv6-only between CE and Border Relay (BR). CPE is 
>> provisioned with an IPv4 address and a range of ports. It does basic 
>> NAT44, but only uses the reserved ports. Then it translates to IPv6 
>> (MAP-T) or encapsulates in IPv6 (MAP-E) and forwards to the 
>> configured Border Relay (BR), which changes it to IPv4. Pro: 
>> Stateless, very efficient. Con: Very little CPE support in home routers.
>
> So, all we need is NAT44 CPE, which only uses a reserved block of ports,
> which is (semi) statically configured by ISP operated gateway.
>
How would you route from the provider edge?

If CPE A has 192.0.2.15 port 1000-2999

and CPE B has 192.0.2.15 port 3000-4999,

how does your BRAS or CMTS or edge router know whether to forward a 
packet to A or B?

You could do policy routing or similarly do deep packet inspection, but 
you'd need a mechanism to provision that information into the provider 
edge router; you wouldn't manually configure match/set policy for each 
customer.

> Pro: Stateless, very efficient, no IPv6 necessary Con: No current
> CPE support.
>
> As for protocol, assuming port mapping on UPnP gateway is statically
> configured by ISPs not changable from CPE side, GetListOfPortMappings()
> of UPnP should be useful for CPEs to know range of ports to be used
> by them.

Do CPEs do this now, or is this another feature to ask vendors for?

Lee

>
>                             Masataka Ohta
>
>