On Wed, 15 Sept 2021 at 06:38, Masataka Ohta < mohta@necom830.hpcl.titech.ac.jp> wrote:
Shane Ronan wrote:
But in fact with local number portability, you cannot rely on the county code to tell you where to route a telephone call anymore.
Not. With geographical aggregation, you may route a call *anywhere* in the destination country.
You mean anywhere in the world. Calls to my number reach my cell phone no matter where I go.
Number portability database is looked up after the call reaches the destination country, which will be used for further intra-national routing, which do not affect country-wise aggregation of international routing table.
Actually the GSM system will query the HLR to find out where to really route the call. Much like LISP actually. Regards, Baldur