shyam bandyopadhyay wrote: Welcome back.
The intention to establish hierarchy is to reduce the number of entries in the global routing table.
True, and rfc2374, though obsoleted, shows a very good way to do so. Though the rfc limit the number of global routing table entries 8k, which many people says too restrictive, we must make the number below reasonably small constant, anyway.
Relating a (networking) region to a geographic region is just to satisfy administrative policies.
Yes, in theory, it is possible, like telephone network, to regulate so. But, it requires tight and reliable connection within all regions and is not very elegant (network partition can be disastrous). It is not acceptable to many ISPs already having addresses, because they must get new address ranges in all the regions, which means massive renumbering. But, it is not a problem if we start over with new network protocols.
If no such requirements arise, establishment of hierarchy becomes easier at the same time address space can be used in a better fashion.
The problem is that, with rfc2374 style addressing, those who can not get a TLA must ask others with TLA part of their address, which means massive renumbering. Automatic renumbering including routers within ISPs, which IETF failed to develop, is absolutely necessary to limit the number of TLAs. My colleagues actually developed automatic renumbering system including automatic rewriting of DNS entries. It works both for IPv4 and IPv6.
By the way, I am thankful to you just because you took the pain to go through my document.
Not any pain. I enjoyed it. Thank you. Masataka Ohta
