On 1/01/2009, at 9:18 AM, Andrew Ruthven wrote:
On Wed, 2008-12-31 at 11:44 +1300, Jasper Bryant-Greene wrote:
How about I just tell you my "phone number" is freddie(a)beer.com, your software looks up "_sip._udp.beer.com. IN SRV", and places a call to freddie at the server returned by that record. It's an optimised, point-to-point connection, and it doesn't involve carrying over antiquities like PSTN phone numbers.
Because that is a solution to a different problem. That says for a domain, you can use SIP to contact some SIP endpoint (what happens for a business? reception only?), whereas in ENUM you can have a number of different technologies associated with a "phone number". For example, SIP, H.323, email, IM, http, carrier pigeon roost, PSTN, etc.
The software you're using to contact me can then work out the best common protocol to use for talking with me. This can include least call routing in the decision process as well, as already mentioned.
The other useful (and also confusing) thing with ENUM is you can have regular expressions. So I could have one record for the entire number range at work which says how to translate that into the required SIP URL to contact each phone.
The technology sounds cool, but do we really want to carry over the phone numbers? Are they really that ingrained in the consciousness of everyone that we can't come up with something better? I'm guessing ENUM records could be inserted for anything, not necessarily reverse-mapped phone numbers under .e164.arpa, so the technology is useful even if we ditch the cryptic strings of digits. Or is it somehow tied to the concept of a phone number? -- Jasper Bryant-Greene Network Engineer, Unleash ddi: +64 3 978 1222 mob: +64 21 129 9458