3 ms·
> an alternative-history-IPv4 with "only" 48b addresses (instead of 64b or IPv6's 128b) would probably also been enough MAC address can be assigned in arbitrar
by NavinF 5y ago
> an alternative-history-IPv4 with "only" 48b addresses (instead of 64b or IPv6's 128b) would probably also been enough
MAC address can be assigned in arbitrarily small blocks whereas IP addresses must be assigned as large prefixes, ideally one prefix per org. Otherwise the internet routing table would be too large. I don’t think 2^48 is reasonable right now without NAT and it certainly won’t be enough in the near future.
Also 48b MAC addresses are kinda small. InfiniBand uses 64b and newer protocols should do the same.
- throw0101a 5y ago> MAC address can be assigned in arbitrarily small blocks Not really. Of the 48b available, the first 24 are assigned to an organization: * https://en.wikipedia.org/wiki/Organizationally_unique_identifier https://en.wikipedia.org/wiki/Organizationally_unique_identi... * http://standards-oui.ieee.org/oui/oui.txt http://standards-oui.ieee.org/oui/oui.txt then they can assigned the other 24b as they wish. This is in some way similar to an IP prefix being assigned, which can then be used however the assignee wishes. 48b would have lasted longer than 32, perhaps delaying the need for NAT (RFC 1631 from 1994), but certainly at some point an address extension would have been needed. Of course in the 1970s it would have been hard/impossible to predict needing more than four billion addresses for a research/academic network.
- NavinF 5y agoYou don’t need an OUI. They sell smaller blocks: https://standards.ieee.org/products-services/regauth/oui36/ https://standards.ieee.org/products-services/regauth/oui36/