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Comment by lmm | Hacker News Reader

The problem isn't the number of addresses, it's the address space fragmentation. The IPv4 global routing table is already 3x the size it should be. At the point where you're just giving every device an arbitrary number, the addresses cease to function as addresses.

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LISP is meant to solve this problem, but it's yet to be deployed outside of the test network. It could also be used to address exhaustion to some extent by allowing the use of prefixes longer than /24 on the internet, although that is not the intention.

https://www.lisp4.net/

https://neverthenetwork.com/notes/lisp/

Full disclosure, the second link is my blog.

I guess this would give us a few years of breathing room by letting us fragment ipv4? Does anyone support this other than Cisco (ie Broadcom/Cavium/Intel/Barefoot)?

Really it's meant to solve the fragmentation that already exists. Cisco developed the standard, but it's completely open.

I believe Cisco is the only large vendor that's implemented it, but there are Linux and BSD implementations, which should make it easy for any Linux or BSD based NOS to implement it in the future.

Honestly this problem will probably be mostly solved in hardware with larger FIBs/TCAMs

Edit - I should clarify the problem I'm referring to here is fragmentation, not exhaustion.

Especially if you stop allocating TCAM memory for the much larger v6 addresses. I hate to think how much memory is sitting out there in routers, configured for 128 bit v6 addresses and never used...

You only need 64 bits for routing v6, and since the address space isn't fragmented the routing table ends up at a similar efficiency level to the v4 one - probably better once you take into account not needing CIDR.

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