Skype on Mobile: North American Carriers’ Backhaul is the Ultimate Bottleneck

Attending eComm 2008 provided lots of opportunity to get an overview of what is holding back the general commercial availability of VoIP on mobile platforms. Let’s start with a slide from Jonathan Christensen’s Wednesday morning keynote presentation where he talked about the infrastructure available when Skype launched in late summer 2003:

Fast forward to Mark Jacobstein’s talk Thursday afternoon on iSkoot, the service that uses the inherent wireless voice network to call a local point of presence. iSkoot then connects the call to a Skype instance on a server and then out to a Skype contact. Mark pointed out that current mobile devices lack the resources – battery, CPU speed and memory – required to have a robust, reliable commercial voice service using VoIP technology. iSkoot has demonstrated how to overcome these barriers with their support for the 3 Skypephone service as well by providing clients for other smartphones, such as Blackberry and Nokia, that take advantage of their architecture to operate IM over the data network but voice over the inherent voice channel.

Brough Turner, CTO of NMS Communications, a supplier of communications platforms for service providers, has studied the details of the Internet backbone from an architectural, operational and business relationships perspective. In an earlier session Thursday at eComm 2008 he pointed out that most cell tower sites in the U.S. have only one or two T1/E1 connections resulting in a bandwidth of 1.5 or 3 Mbps connection to the Internet for wireless phone users:

Net-net: As spectral efficiency keeps improving with HSPA and so forth, backhaul is rapidly becoming the bottleneck.

Cell sites are fixed locations. The vast majority are in urban or suburban neighborhoods. Their bandwidth requirements will continue to grow, indefinitely. In any rational world, one would purchase dark fiber to most of these sites. In the irrational real world that is the US today, dark fiber is available on long haul routes but is extremely hard to come by in populated areas where most cell sites are located.

Even with the appropriate smartphone resources and 3G/4G wireless networks at the cell sites, North America has a lot of dark fiber to lay to achieve the 99% VoIP wireless infrastructure conditions analogous to those that allowed Skype to launch so readily over wireline broadband networks in 2003. And this is probably one of the strongest arguments for stating that carriers need to focus on the "pipes" and leave the content and services provisioning to third parties.

But, what about the WiFi option? I used Truphone successfully several times during my time at eComm 2008 and VON.x to complete calls from my Nokia N95. But it always required a good WiFi connection — not always (and definitely not reliably) the case for the overtaxed WiFi service provided at most conferences I have attended where large numbers of users are attempting to connect to the Internet through a <6Mbps pipe1. And I had to make sure I charged the battery every evening; even then it would not always last through the day. I still find my best WiFi connections at locations, such as my home office, where individuals have control over the "backhaul" connection and may only have two or three users at most going through the access point. Maybe we all need to take a guerilla rebel approach and install WiFi cells "everywhere".

Or maybe we should all move to Stockholm. As Rudolf van der Berg says in a comment to Brough’s post statess (and later posted); "In the end life is simple: Without Broadband there is no Mobile Broadband."

Meanwhile I’ll continue to use iSkoot or Mobivox in situations where roaming charges accessing the voice network don’t overwhelm me. And I’ll try out the MaxRoam SIM I received while at VON.x where it does.

Photos courtesy James Duncan Davidson.

1 Only at Scoble’s BlogHaus at CES, with a > 20MBps connection, has there been reliably sufficient WiFi bandwidth to handle up to 50 bloggers, often sending video, concurrently.

Tags: eComm 2008, Skype, Mobile VoIP, Jonathan Christensen, iSkoot, Mark Jacobstein, NMS Communications, Brough Turner, Truphone, MaxRoam, Mobivox, Rudolf van der Berg

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About Jim Courtney

Bringing over thirty years' experience in the sales, marketing and management of cutting edge technology businesses.


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