Mobile operators are hoping to benefit from the move to all-IP networks as much as their fixed-line counterparts, with the promise of cost savings and compelling new services.
But there is a snag: The shift to bandwidth boosting technologies such as high-speed downlink packet access (HSDPA) will place huge demands on mobile operators' backhaul networks.
They will need to increase capacity on their backhaul networks significantly if they are to cater for increased bandwidth demand.
'HSDPA will do to our interface what DSL did [for fixed operators],' says Andy Jones, head of transmission at Vodafone.
Higher-speed networks simply move the capacity problem from one part of the network to another, says Jones. 'HSDPA unlocks the national bottleneck, [but] the bottleneck moves and becomes the backhaul,' he says.
This raises a challenge that fixed operators are already grappling with. One answer would be for mobile operators to stick with what they know and increase capacity through more microwaves and leased lines, but that is expensive.
Another option, and one being adopted by some of the incumbents, is to move to new access and backhaul networking technologies, notably Ethernet.
But where fixed operators have been acknowledging the need to up the ante on NGN spending, mobile operators are faced with the need to cut expenditure. Vodafone, for one, expects revenue per bit to fall dramatically in coming years. 'The cost base needs to step down in a way we have never seen before,' says Jones.
Mobile operators have been converting their core networks to all-IP for some time.
Vodafone, for example, started converting its core networks from TDM switching to MPLS in 1999, says Jones.