RE: SRH insertion vs SRH insertion + encapsulation

[Ron Bonica <[e-mail]>]

Ole,

There is a big difference between translating a packet's source/destination address and adding something to a packet. The best way to explain this difference is with an analogy.

Assume the following:


  *   I, Ronald, am conversing with an Italian speaker through a translator
  *   I say to the Italian speaker, through the translator, "your shoe is untied"

It is OK for the translator to tell the Italian speaker, "Aldo says that your shoe is untied". He has translated my name into Italian, but not changed the message.

It is not OK for the translator to tell the Italian speaker, "Aldo says that your shoe is untied, and that you are ugly ".  If he were to do that, he would be originating a message and attributing it to me.

                                                                     Ron




Juniper Business Use Only
From: Ole Troan <[e-mail]>
Sent: Saturday, September 7, 2019 11:03 PM
To: Ron Bonica <[e-mail]>
Cc: Robert Raszuk <[e-mail]>; Mark Smith <[e-mail]>; draft-voyer-6man-extension-header-insertion <[e-mail]>; [e-mail]
Subject: Re: SRH insertion vs SRH insertion + encapsulation

Ron,

IMHO, EH insertion modifies the semantics of the IPv6 source address. Today, the IPv6 source address indicates the source of an IP packet and *ALL* of its contents. If transit routers are allowed to insert extension headers, downstream routers can no longer identify the source of a packet and all of its contents.

Granted, in some cases, transit routers are allowed to modify a packet (e.g., Hop Count, DHCP, mutable options). But there is a big difference between changing a field whose value is know to me mutable and inserting a new option.

6296?

And I am pointing that out because of what feels like moral righteousness and hypocrisy to me, not because I think header insertion is a good idea or even doable.

Ole