So the mobile carriers will have to respond to the challenge, perhaps by wireless-enabling their phones and signing up with Wi-Fi service aggregators such as iPass or Swisscom so that they can "flip the situation on head and... pass landline calls to BT and they get a proportion of our income not the other way around".
Although Vodafone refused to comment, Longbottom says: "There are many different options open to the mobile operators, but they are likely to become less mobile and the fixed operators less fixed. This means that they'll be back where they should be - competing on pretty much the same set of services."
Therefore, while both the mobile carriers and BT will initially need to work together to create the market, "it will eventually boil down to who is fleeter-of-foot".
But, points out Mark Blowers, a senior research analyst at Butler Group, to ensure that the playing field remains level, the regulator, Ofcom, may have to intervene.
"From a regulations standpoint, the danger is that BT will use its strong position with fixed line networks and the last mile so that mobile operators and smaller start-ups find it difficult to compete in providing similar services. So it's important that Ofcom looks into this area because it potentially opens up a can of worms," he says.
One possible solution for the mobile operators could be to partner with other players such as systems integrators and ISPs "that understand internal communications so they can come up with a more integrated solution", says Alex Black, strategy director at network consultancy, Affiniti.
While this will present mobile carriers with organisational and technical challenges, the move to convergence will have similar repercussions on their customers as, in future, they will likewise have to think about their communications infrastructure in a more integrated fashion, adds Black.
"Today, the people in organisations that procure wired and wireless solutions are different to those procuring fixed line telephony, but in future that's going to have to change so how to integrate all these different communications technologies together is going to be a challenge for everyone," he says.
But is there is actually any demand for converged fixed and mobile networks or is this simply another technology-driven initiative that the industry is trying to foist on unsuspecting customers?
Black, for one, believes that there is "a lot of pent-up demand today and companies in which there is high mobility are just waiting for the technology to catch up".
"One of the big issues today is how you allow communications, while keeping costs under control, especially in relation to mobile spend. Another issue is how to make better use of expensive offices and optimise resources. One way to do this is hot-desking, and allowing staff to use their phone of choice whether they're in the office on moving around will help here," he says.
Many companies would like to have a single service provider, especially when it comes to billing. A lot of organisations simply have no handle on how much their communications costs are because they receive one bill for fixed line calls, another for on-campus voice, several for home line usage and "a morass" for mobile calls. This lack of clarity, in turn, prevents them from being able to control costs by negotiating effectively with their providers.
