Re: [External] Request for information - Challenges in routing related to semantic addressing

[Tony Li <[e-mail]>]

Hi Toerless,


> You meantion locator and identifiers as unresolved. Do you think this should be subject to
> more work in IETF and/or IRTF (routing) ? If so, how ?


Not at this point, no.

We are not yet wise enough.

We looked carefully at this. One option was fixing the architecture. The other was a band-aid. We recommended fixing the architecture. The community decided that the band-aid deserved all the effort. 

The band-aid has yet to deliver anything meaningful and the architecture is not fixed.  Pretty clearly, the pain level has not reached the threshold where we will act wisely and in our own best interests. If only there was some group that was responsible for the architectural oversight of the network. But alas, there isn’t.


> You mention architecture fundamentals and routing / addressing ties. Do you think there
> such fundamentals that would transcend what i would call different "address semantics",
> e.g.: unicast, multicast, ICN ? I am asking because if there where such fundamenals of
> interest, maybe working on them would ease the ability to operate multiple semantics,
> add and/or extend them.


Yes, an architecture has to define all of the uses of the addressing field and explain how routing will make use of the address in each and every case.


> You mention protocol field / address overload. I completely agree, but why then have we
> not attempted to work to easier extend instead of overload packet header / addresses ?


Because extensibility at the network layer is seen as Evil.  We decided long ago that it was impossible to have extensible addresses, despite the fact that we had working hardware. Instead, we kludge to add more fields onto the network header, requiring MORE bits to be sucked into hardware, and much more complexity than if we had just made the address field flexible. And we do so in a way that is wholly incompatible with existing hardware AND wastes gigantic amounts of bandwidth.  Good job guys!


> E.g.: I look at TSVWG L4S carving out even more semantic out of 2 ECN bits and grumble
> about printing a t-shirt "40 years of IP and all we have for QoS is still 8 bit".
> (alas, corona times are no fun for t-shirt junkies).


And it’s still more than is truly needed. ;-)


> Personally, i wish we would never ned to overload semantics of addresses, because we are a) not
> wasting address space (as you point out) and can b) amend adress space, when needed for new semantics.
> Now: Why do we not amend our protocols to allow for that ?


Because touching the architecture is the third rail.  It is our sacred cow. Pitchforks and torches come out as soon as you talk about fixing IPv6.

Our grandchildren will hate us because we cannot get past our own myopia.  We ossified the inferior and declared it inviolate.

Regards,
Tony