Re: [Softwires] Moving forward with 4rd-T, 4rd-E & 4rd-U

[Ole Trøan <[e-mail]>]

> More over, 4rd-U claims to solves a number of issues that the MAP suite of documents does not address. It would be beneficial to have
> a discussion on the mailing list  to see if a) those issues are important or not and b), if they are, are they properties of 4rd-U or could they be solved as well
> in MAP, they just have not been addressed there yet.

here is a comparison table of the feature differences between MAP and 4rd-U.
(try a fixed width font if it doesn't survive your particular MUA mail mangling algorithm.)

Appendix A.  Comparions of stateless A+P solutions

   +-------------------------------+----------------+------------------+
   | Feature                       |       MAP      |       4rd-U      |
   +-------------------------------+----------------+------------------+
   | Encapsulation                 |        Y       |         Y        |
   | Translation                   |        Y       |         Y        |
   | Hub and Spoke mode            |        Y       |         Y        |
   | Nested CPE                    |        N       |         Y        |
   | End-user prefixes > 64        |        Y       |         N        |
   | E-mode: Support for IPv4      |        Y       |         N        |
   | options                       |                |                  |
   | T-mode: MF bit and TOS bits   |        N       |         Y        |
   | transparency                  |                |                  |
   | T-mode: Checksum              |   L4 rewrite   |        CNP       |
   | H & S set bit 79 needed       |        N       |         Y        |
   | Interface-id                  |     RFC6052    |      V octet     |
   | MAP traffic identified by     | Address/prefix |  Interception of |
   |                               |                |      V octet     |
   | Port mapping algorithm        |   GMA. Prog.   |    GMA. Fixed    |
   | Fragment forwarding on BR     |        N       |         Y        |
   | without reassembly            |                |                  |
   | Shared fragmentation id space |        N       |         Y        |
   | BR rewrite fragmentation      |        N       |         Y        |
   | MSS update                    |        Y       |         N        |
   | Complete IPv6 address /       |        Y       |         N        |
   | prefix                        |                |                  |
   | Provisioned with DHCP         |        Y       |         Y        |
   +-------------------------------+----------------+------------------+

                          Table 1: A+P comparison

let us make it clear that these two solutions are solving exactly the same problem, and they solve it in the same fundamental way (A+P). the differences we're talking about here are what whistles, bells (and dongs) we want to add on to the base specification. consider it a buffet, any feature from one of them can be applied to the other.

cheers,
Ole