Re: [Int-area] WG Adoption Call: IP Fragmentation Considered Fragile

[Joe Touch <[e-mail]>]

On 2018-08-02 08:38, Ole Troan wrote:

> Joe, 
> 
>> I am not ignoring them; I'm claiming that they all have the same inherent deployment and implementation limitations.
>> 
>> Just because operators/vendors "want" to do otherwise does not make it possible.
> 
> There was IETF consensus behind those documents (A+P).

You mean the *experimental* RFCs that describe an approach that doesn't
update RFC791? (i.e., RFC6364?) Or something else? 

> In the _new_ IPv4 Internet architecture the IPv4 header looks like this: 
> 
> 0                   1                   2                   3 
> 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2  3 4 5 6 7 8 9 0 1 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> |.    0x45      |Type of Service|          Total Length         | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> |         Identification        |Flags|      Fragment Offset    | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> |  Time to Live |      6|17     |         Header Checksum       | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> |                       Source Address                          | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> |                    Destination Address                        | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> |         Source Port           |     Destination Port          | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> 
> If the the ascii art comes through.

A+P didn't update 791. There is no *new* IP header. 

The diagram above is a combination of IP - without options, notably -
and only two specific transports. It isn't an IPsec'd packet, a tunneled
packet, or any other transport. The Internet is not merely TCP and UDP
over IP with no options. 

> In contrast to NAT the address and port fields are not rewritten. Only used for forwarding.

And there may be limits to where that kind of approach can be deployed.
The jury is still out - this is experimental. 

Joe