And, heck, yes, that’s when the idea started: what if … one takes the digitized voice and puts it onto an Internet link instead ISDN? Little did I know back then about the technology involved, but … this as well as technology changed ;)
I think my first VoIP experience was with Netmeeting some years later; for me, non-Windows throughout the Eighties and Nineties, it wasn’t a fun experience. Anyway, time and me moved on, and around the year 2000, I remember a huge fuzz about “Internet Telephony” in general (for it being “the future!”) and something called ENUM (as “Telco-Killer!!!11!elf”) specifically.
Well, from my perspective, ENUM never began to fly, at least here in Germany. The idea was nice, but technology wasn’t there yet to get rid of the Telcos and their dedicated voice links by just looking up you remote partie’s SIP address via ENUM and connect via IP directly.
And then there were the politics. Sure, I don’t want my neighbour to “maintain” my number’s ENUM settings, but on the other hand, I don’t intent to pay someone, anyone, for me being able to maintain it at all.
The most obstacle these days imho is: flatrates are the default now. There is just no real incentive – besides “because I can” ;) – to ENUM anymore. Compared to the el cheapo voice carriers of the early years, 2000 to 2006 maybe, which usually used VoIP to be able to offer cheap rates at all, VoIP is nowadays a reality, used in several ISP and Telco backbones as default transport for voice traffic anyhow — and the user usually neither knows nor, because of good quality, cares.
That said, I stumbled upon freenum.org and ISN on my recent configuration sessions with my Asterisk server. The basic idea behind ISN, or “ITAD Subscriber Numbers”, is to use the ITAD number, or Internet Telephony Administrative Domain, which IANA assigs to one on request, to use as a “domain” for adressing/routing calls. Or, to quote The ISN Cookbook:
ISNs (ITAD Subscriber Numbers) provide a method for inter-domain numeric SIP addressing. An ISN is formed by joining a domain-local subscriber number to an ITAD (Internet Telephony Administrative Domain) number, using an asterisk as the delimiter. For example, subscriber 1234 in ITAD 256 would have ISN: 1234*256
ITADs are actually a leftover from “Telephony Routing over IP (TRIP)”, some other means of using the Internet for voice call routing, which never hit the center stage.
But the idea of ISN sounded like fun, and it’s actually something with real use cases even from normal phones: you can dial an ISN from a phone, as all you need are the ten digits and the asterisk.
I did some investigation and found that the prefix “0122” (whole of 012, actually), is unused in the German numbering plan, thus I choose that as a prefix for dialing ISNs. Now, anyone in the household can use e. g. 01223246*1071 to connect from any DECT handset or ISDN phone – via the Fritz!Box that routes 0122 to the Asterisk in the DC – to dial an echo test run by rotornet.net in Florida (all ITAD data is public):
-- Executing [01223246*1071@7270-EG:1] Goto("SIP/swiss1-000002b2", "dial-freenum2,3246*1071,1") in new stack
-- Goto (dial-freenum2,3246*1071,1)
-- Executing [3246*1071@dial-freenum2:1] Verbose("SIP/swiss1-000002b2", "2,Performing ISN lookup for 3246*1071") in new stack
-- Executing [3246*1071@dial-freenum2:5] Set("SIP/swiss1-000002b2", "isntarget=3246@sip.rotornet.net") in new stack
Yeah, I know — besides geeky me, no-one in my household will use it, but I still like the idea and it’s dirt easy to implement ;)
I have set up 98735*1796 (yepp, that’s “wusel at 1796” ;)) to get forwarded to my mobile, so if you’re running an Asterisk system as well, feel free to ring my ISN for a quick chat ;)