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iNum Gaining Ground With Traditional Carriers

Voxbone’s iNum service this week announced that Verizon, British Telecom and Belgacom are now supporting their +883, the country code for “planet earth.”

From the companies press release:

“Gaining recognition of iNum from traditional, non-VoIP carriers is critical to iNum’s long-term success and, more broadly, is a major industry milestone, signaling a pivotal change in the thinking of the world’s national carriers,” said Rod Ullens, CEO of Voxbone. “With short- or long-term IP conversion plans of their own, most incumbent operators are no longer fighting but rather embracing Internet-based communication services.”

You can read the entire press release here.

I would hope that if Verizon gets in the game that other North American carriers will eventually do likewise.

We should be 100% clear about what this is exactly. iNum is a carrier peering mechanism. It’s a means for the carriers to connect via IP where in the past they have connected by TDM means. In essence iNum takes the PSTN out of play when calls get passed between member carriers. It also stays with a numeric address scheme allowing that traditional desk phones can make iNum calls with the complexities of dialing by SIP URI.

One of the big opportunities that iNum presents is the chance to spread the adoption of HDVoice. If the carrier/service provider at each each is IP-based then a pure IP call path is ensured. iNum already supports G.722 and has expressed some enthusiasm for Skype’s SILK.

So how does this directly benefit a non-Verizon, British Telecom or Belgacom customer? Well, there is a growing list of iNum supporters, which happens to include Gizmo5. According to the iNum FAQ:

If you are a Gizmo5 user, you now have an iNum.

To know what’s your iNum number look for your Gizmo5 SIP number, which looks like 1-747-XXX-XXXX and replace the [1-747] with [883 510 07].

Example: If your Gizmo5 SIP number is 1-747 123 4567 then your iNum is +883 510 071 234 567.

Since I’ve had a SIP Phone/Gizmo5 number for an eternity I decided to try a little experimentation involving iNum calls. For a long time I’ve had my Gizmo5 number permanently call forwarded to an OnSIP SIP URI.

Initially I tweeted that I had an iNum and would anyone following my twitter stream be able to try calling me via that route. Three people responded, but only the last could place the call successfully.

The first to try was Aswath Rao who is actually on Verizon service. He received a fast busy signal for his effort. When the second person tried and failed I though I’d best take matters into my own hands.

I looked up the list of local numbers numbers that expose iNum in areas where there is no carrier participation. There’s a Houston local number on that list.

I called that 713 number from my cell phone and was greeted by a prompt to enter the iNum I wished to reach, which I did. The call was completed and rang my IP650, but I could not answer it. Call signaling was making it correctly, but the media was not.

I decided to try and simplify the call path so I logged into the Gizmo5 control panel and removed the call forwarding to the OnSIP URI. I then set my Eyebeam soft phone to register with Gizmo5 and tried the text call from my cell phone once again.

This time the call went through correctly and I was…as is so often the case…talking to myself.

T-Mobile cell phone > Local iNum access > iNum > Gizmo5 > Eyebeam

Just about the time that I hung up that call @maximCH called me from his Asterisk server in Switzerland. He told me that his Asterisk dial plan  was dialing iNum via Gizmo5, so it was perfectly logical that the call completed. It was essentially in-network for Gizmo5, only referencing iNum numbers.

He then called back from his Swisscom cell phone. He has found that Swisscom also routes iNum, although they can’t quote him a rate and have suggested that the calls are actually free!

So it seems that by virtue of the fact I have a Gizmo5 number I also have an iNum number. What does that get me? Very little really. For the moment iNum is actually less useful then calling by SIP URI. That is, I know more people who are accessible via SIP URI.

However, as iNum uptake grows it may enable greater use of wideband calling. When you call my iNum you are essentially assured of an all IP call path, and so a wideband call. That assumes that your end is IP-based. If you’re calling from a VZ POTS line you won’t be getting HD audio, even if VZ routes the call.

iNum may also flatten the world from a cost perspective. For example, Skype charges 2.1 cents/minute for termination to iNum numbers. Considering that the number could ring anywhere on the globe that’s got to be on average below the cost of traditional calls. I doubt that many people will be as fortunate as @maximCH and enjoy free iNum calling from mobile carriers. Such confusion probably won’t survive if iNum usage grows in a meaningful way.

This Post Has 13 Comments
  1. If I understand the process for making an iNum call from T-Mobile, you had to dial a 10-digit local access number followed by a 15-digit iNum number. 25 DIGITS to place a phone call. That’s absolutely NUTS! What’s wrong with ENUM. Register your regular 10-digit phone number once and point it to a SIP URI. All subsequent calls to your existing 10-digit number are free using services supporting ENUM: Seems to me that would make a lot more sense for the major carriers.

    1. I’m not disagreeing with you, such laborious calling sequences are unlikely to be used by most people. As I said, this was a little experiment inspired by the iNum press release and based upon having an existing Gizmo5 account.

      Of course, if you were implementing the dialing in an Asterisk or Freeswitch dial plan the call to the access number would be a fixed part of the dial plan, not something that you would manually dial each time you placed a call. The would shorten the number dialed somewhat.

  2. Nicely written piece. This is a major advance when any major player integrates It’s a shame that Gigaset isn’t on the list though. With their pre-configured SIP accounts on phones, they could have a marketing field day with this. I’ve ordered A580s for family members for the simple reason that they can just plug it in and it will work. It will be interesting to see what AT&T do with this. Also, this makes sense as major providers deliver SIP (in controlled introduction) to their large customers who consolidate trunking using SIP. This is all about integration to SIP endpoints for the masses (non-voip customers).

    1. I’m not clear that I understand what you’re getting at. Gigaset run their own SIP Registrar at Gigaset.Net. That’s all. AFAIK, Gigaset.Net accounts are not resolvable via external means like iNum or ENUM.

      Gigaset.Net is extremely handy when you’re gifting a phone to relatives because it works straight out of the box, but it’s only useful when calling other Gigasets. If you were to take the trouble to provision the phone with a free account from someone like OnSIP, SIPGate or IdeaSIP then they’d have the option to make/receive calls from regular phones as well, albeit at a price.

      1. Therein lies the opportunity for Siemens, making resolvable via external means.

  3. The biggest problem we’ve had with iNum is that Voxbone has been less than excited about allotting the iNum numbers to SIP providers. We tried to get some. Went through their interop procedures. Everything tested fine. They asked how many users we have to pass them out to, and when it wasn’t in the six digits, they lost interest entirely and stopped even answering email queries.

    ENUM, at least, we were able to work with. But any time you get one VERY self-serving entity controlling your access entirely, the system breaks down altogether.

    iNum will never fly more than eNum until you can get iNum numbers as easily as you can get domain names. Until then, it’s all going to be one entity acting as an all-powerful gateway and determining based on their OWN needs whether or not you get to join the club.

    Alas… this is the problem with ALL aspects of VoIP beyond the basic SIP to SIP arena. Giant telcos don’t care about you unless you’re going to visibly impact their yearly bonuses. Mid-level carriers don’t care about you unless you’re going to help them win the favour of the giant telcos. And at the other end, customers don’t really care unless it’s all free. At the end of the day, you’re left in this sort of constant struggle to even provide service to your customers, who turn over faster than you can say, “there’s a new VoIP site out there.”

    Anyone building in this space needs to live the idealism and love it to death, or the end result is going to be the same as what we started with: 1 or 2 giant providers setting the rules and setting the rates, and deciding that you really only NEED features X, Y, and Z and you’ll be paying W+taxes+fees+kickbacks+bonuses for them.

  4. @Nerd Uno
    The use of access numbers is a temporary solution until the iNum numbers are directly dialable from all major telcos and other service providers.
    Getting this direct dialing implemented with all telcos is a long process because all switches around the world need to be updated.
    But we are confident that eventually we will get there. You can expect some exciting announcements in the near future.

    About the length of the numbers (15 digits):
    People are increasingly using address books and do not even remember the phone number of their contacts…
    When this is the case, do you care whether a phone number has 3, 10, or 15 digits ?

  5. @Neil Fusillo
    I’m not sure why you say that we are only interested in assigning iNum numbers to large service providers ?
    We have assigned iNum numbers to service providers of all sizes, and still do, and we actually try to make it as easy as possible to obtain and configure iNum numbers.
    And as you probably know, iNum numbers are assigned for free to service providers.

    I checked your correspondance with our iNum department, and noticed two items:
    1. You already have 100 iNum numbers assigned in your account since several months
    2. We sent you a last email on december 22, 2009 in which we asked some questions, but never received a response

    Maybe there has been a misunderstanding ?
    In any case we have re-sent this last email previously sent to you, and happy to take it from there…

    1. Apparently, there were some vanishing emails involved in this. But things have worked out. We’ve recently received a block of iNum numbers and we’ve begun to distribute them to the users (with some interface elements missing at the moment, but those should be worked out by the weekend).

      It seems that it was a misunderstanding, and I thank you for checking into it.

  6. i love this idea
    with the Enum i can use my mobile and the acces number of betamax and call gizmo numbers for free !!

  7. Hey Michael,

    Did t-mobile or any of the other carriers ever charge you for the calls to inum’s you made? Did they charge you like an international call or did it just come off your minutes?


    1. The only time I ever tried dialing via inum was through an IdeaSIP account, and it cost me nothing. IdeaSIP provides my inum number, but it’s never been used beyond one or two experimental calls.

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