But in fact with local number portability, you cannot rely on the county code to tell you where to route a telephone call anymore. Which is many calls result in a data dip to provide you the routing information from a central repository.
Shane On Tue, Sep 14, 2021 at 10:07 AM Masataka Ohta < mo...@necom830.hpcl.titech.ac.jp> wrote: > Eliot Lear wrote: > > > Operators and > > router manufacturers at the time pushed TUBA, which was considerably > > less compatible with the concepts used in v4 because of variable length > > addressing. > > That address length is variable is not a problem at all. Byte-wise > barrel shifters by hardware for CLNP are trivially easy and light > weight to implement. > > The real problem is on the number of prefix bits which must be > looked up by backbone routers, which means IPv6 abandoning TLA > is hopeless. > > NSAP addresses, which essentially are telephone numbers, assume > geographically aggregated addresses at country level (so called, > country code), which is why they don't need large global routing > tables. > > 8+8 has nothing to do with the problem and LISP came a lot later > as a broken solution for the problem. > > Masataka Ohta >