> On 17 Dec 2021, at 9:35 am, Dino Farinacci <farina...@gmail.com> wrote: > >> If we don't want to share a common transmission resource, then why do we >> need globally unique addresses to use in IP packet headers? Locally unique >> addresses would do just as well. > > Just to answer this question specifically. We may not need globally unique > addresses. But I need a unique address for anyone I want to talk to and I > don't care what transmission networks my packets traverse. > > Therefore, we need unique addresses. However, lets say an address is 24 bits > long and we use a random number to generate the address. It is unlikely that > there will be an address collision for all the things I want to talk to. So > to me I get my unique address. Is it globally unique, well no, but maybe it > doesn't have to be. > > But there will be hosts that want to talk to everyone in the world or at > least beyond an address collision domain, so we default for the desire to > want/need globally unique addresses. So simply using a random number > generator for an IPv6 address may get us there and work sufficiently. > > Comments?
I have no idea when I last sent a packet from my client host to any other client host. Somewehere is the massive stream of packets that come from the data centres nearby is a lonesome packet that made its way through. maybe. or maybe not. Such packets are statistically insignificant in volume, and, more importantly, economically insignificant. This latter observation is the critical one. QoS lost its way in the public Internet because it was obvious that it was costing far more than the marginal revenue it was raising. (It survived in enterprise environment largely because in enterprise environments then network is not treated as an isolated cost centre.) If all my packets come from highly replicated data centres then all that matters is my endpoint identity (i.e. address) relative to that data centre. A unique global identity is a pointless (and expensive) luxury. So, to repurpose some graffiti from the 1970’s, we need globally unique addresses like fish need bicycles! :-) regards, Geoff _______________________________________________ Int-area mailing list Int-area@ietf.org https://www.ietf.org/mailman/listinfo/int-area
