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E164.org - A sane alternative to PSTN call routing
As I wrote about earlier, I'm really enthused about direct VoIP call routing that doesn't rely on "the phone network" (PSTN). It's silly to think that two VoIP users would need to route their call through the "real" phone network in order to talk to each other. Why should I pay NuFone or VoicePulse in order to place a call to another asterisk user out on the internet? Doing SIP URI dialing is a direct and effective approach to this goal and I'm happy to support it whenever possible. It's better to call "nugget@macnugget.org" than it is to call one of my various "real" phone numbers.
With most telephony hardware, though, it's either impractical or downright impossible to do URI target calls. My cordless phone will never be an appropriate tool to call "nugget@macnugget.org" due to its number-only interface. Gobs of legacy hardware and software (including the Caller ID subsystem we all rely on) has no concept of non-number phone numbers. Thankfully, there's a solution which is elegant and effective.
E164.org is a non-profit ENUM registry of telephone numbers. Simply put -- they maintain a DNS-based listing of PSTN telephone numbers which can also be reached directly via VoIP. Instead of relying on the end user to know the URI of any particular phone number or person, the e164 registry allows it to be handled automatically within a system's dialplan. With e164, URI-target calls can become just another channel to be considered during least cost routing (LCR) tests when a call is placed.
As an example, I've registered my home phone number with e164.org. Remote systems can now look in the e164 registry and discover that as an alternative to dialing the number itself on the PSTN that it's also possible to reach the same target directly using IAX2 or SIP. It then becomes a trivial matter for the remote side to contact me directly. This saves us both money and also yields a call routing with far less indirection. A direct call is likely to be cleaner, with less latency, and easier to manage.
I've registered my three PSTN phone numbers with e164.org and I've incorporated their sample asterisk dialplan into my own. I can do just normal 10-digit dialing with even my old analog phone gear and still benefit from direct VoIP call routing when it's possible.
The beauty of this approach is two-fold. First, it is invisible to the end user who is actually placing the call. Just as they don't really care which long-distance carrier is switching their call, they likely also don't care about URI-target VoIP. To the end-user, they have simply dialed the normal phone number and been connected to the person they dialed. However, all the cost and performance gains that come from direct VoIP routing are enjoyed. Secondly, it's failsafe -- if the e164 enum lookup fails for some reason, the dialed number is the "real" number. The fallback to normal PSTN routing is perfectly usable.
e164.org adoption is growing. Asterisk, SER, Cisco, and a bunch of other companies have already added e164 support to their products. It's a good solution to a problem that's worth solving.
Next: Skype, bad karma but good connectivity
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