Fibre network vendor Geo has criticised a recent Ofcom report which suggested using the UK's alternative utility infrastructures, including the sewers, to accelerate the roll-out of 'fibre to the door'.

Geo chief executive Chris Smedley said that considerable hurdles need be overcome if sewer-based optical fibre solutions are to be seen as an alternative to BT's local access network in residential areas.

The large trunk sewer network in London's Victorian sewer system is ideal for the installation of high-speed optical fibre for businesses in the centre of the capital.

But Smedley claimed that the ability of sewer-based networks to deliver the same advantages to local residences remains unproven.

"The sewer systems in outer London and other cities, not to mention suburban and rural locations, are a very different proposition as they are much smaller or, in some cases, non-existent," he said.

Smedley called on Ofcom to investigate the status of the duct networks owned by BT and Virgin Media.

"Upgrading these [networks] to optical fibre is the most likely way of rolling out a next-generation national network to UK homes and businesses," he said.

Geo already operates an 80km optical fibre network based in Thames Water's London sewer system, and said that rolling out networks in sewers comes with its own set of challenges.

"The sewer companies will not tolerate new network deployment if it impairs their own ability to provide services," said Smedley.