Re: [spring] SRv6 compression

Tony Li <> Tue, 03 August 2021 15:40 UTC

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Date: Tue, 3 Aug 2021 08:40:10 -0700
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Subject: Re: [spring] SRv6 compression
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Hi Robert,

> I beg to differ on the "forever" part. Which forwarding technology well maybe other then IPv6 is lasting forever. Take ATM, take FR, take even MPLS. 

How about IPv4?

It’s very true that link layers can fall out of popularity. Yet the hardware lives on.  I have hardware that forwards CLNS, IPX, and Token Ring. I don’t have a use for it, but if I did, it still works.

> I am questioning the "forever" part specifically based on control plane proposal I published to accomplish many similar objectives with no SRH at all - ultimate SRH compression :) Can't beat that. 

Yes, new proposals can obsolete things.  That’s ok, that’s the normal evolution of technology.  

The point that I’m trying to make is that what we’re doing might well take off.  If it does, we will be stuck with it for a very long time indeed.

Steve Deering, the father of IPv6, said it was specifically designed to last only 20 years, becuse we would need to change the network layer that frequently as we learned things.  He said that 30 years ago.

Look at the north American two prong electrical plug. Still widely used, dangerous, and something that we’re stuck with.

Ditto for 120V 60Hz power.

Get it right, because if it does catch on, our great grandchildren will have to live with it.