T-Mobile is blocking calls from its network to mobile VoIP operator Truphone, in a dispute over costs that gets to the heart of the struggle between mobile operators and VoIP providers.
Customers on Truphone's beta service can connect fully, but T-Mobile has blocked calls to a number range (07978 8xxxxx) on which Truphone is planning to launch a full commercial service, diverting calls to a recorded message saying they have misdialled.
"This amounts to T-Mobile being able to veto a new entrant into the market," said James Tagg, chief executive of Truphone, accusing T-Mobile of abusing its power. "This would put telephony back 100 years, to a time when interconnections were not assured."
T-Mobile says it isn't refusing to connect, it is simply negotiating over the price it pays to Truphone when it connects a call to its network. As a mobile operator T- is required to 'make calls or otherwise transmit electronic communications to every normal telephone number', including those owned by VoIP operators.
Ofcom has published rates that operators are allowed to charge for interconnection to their numbers, and says these fees should be "fair and reasonable" and "transparent". However, Ofcom only states they apply to mobile networks, according to Dean Bubley of Disruptive Analysis, leaving a possibility for mobile operators to discriminate against those they regard as not being "real" mobile operators.
T-Mobile says Truphone is not a mobile network and shouldn't get paid as much as a mobile network would. "Other operators have invested huge amounts of money into their networks. Truphone has no network to maintain," said a T-Mobile statement. Truphone is asking for the same rates as mobile networks, and being offered a much lower rate, which it claims is below its costs.
"T-Mobile will argue that it is not 'blocking' Truphone but is merely negotiating on price," said Tagg. "T-Mobile receives 35p per minute from its customers but is offering only 0.21p per minute to Truphone even when Truphone's costs are 9p per minute to terminate the call. T-Mobile is blocking our numbers unless we accept this loss-making offer and, since T-Mobile is the only company that can route calls from its customers it has a complete veto on the Truphone service."
Confusingly, T-Mobile spokesman Simon Marks is quoted as saying: "It's not up to us to decide what kind of network Truphone is," although this is exactly what T-Mobile is doing. Truphone's numbers start with "07", and any customer dialing them would expect to pay the full mobile interconnection charge, as levied by other operators (including Vodafone which has backed down on an earlier effort to block Truphone).
In the run up to its commercial launch Truphone has recently showed extensions to its service, including support for SMS-over-IP, VoIP over 3G, and 'presence' capabilities so users can see which other Truphone users are currently available by VoIP.
Despite T-Mobile's hostility to VoIP, the company's parent Deutsche Telekomm has invested in VoIP, in the form of provider Jajah; it also connects with VoIP services it approves of, including BT's Fusion service.
For more information, our sister site Techworld has a comprehensive VoIP resource page.