Fibre mains cable could take optical nets mainstream

Mitsubishi embeds plastic optical links into household wiring

A new and potentially cheap way to implement optical home networks uses plastic fibre within mains cable – allowing buildings to be wired for power and data at the same time.

The system could prove popular with developers wishing to future-proof  new or renovated buildings, if and when it conforms to UK regulations.

The idea of combining fibre and mains cables was mooted last year in Test Bed but it turns out that Mitsubishi was already working on it. The system uses plastic optical fibre (POF), which is already widely used for data links in cars and is said to be easier to install than glass – Mitsubishi claims a connector can be put on in 40 seconds.

It lacks the virtually unlimited bandwidth of glass fibre (Mitsubishi rates it at up to 800Mbits/sec) but unlike electrical cables it is immune to interference and creates none.

The system was shown at the IPTV Forum in London by Austrian specialist Homefibre, which supplies modular optical networking kits including combined mains and network sockeys..

Homefibre modules uses tiny optical transceivers and chips from Cork-based Firecomms. These fit inside connectors into which you simply push the sheathed fibre. As with the Tenvera system, different modules can be made to support different protocols such as USB or Ethernet.

Hugh Hennessy, vice president of European sales, showed how POF connection can be made simply by pushing the end of the cable into a terminator. “It is much easier than terminating an Ethernet cable,” he said.

He revealed that the system can easily cope with 100Mbit Ethernet but not gigabit, except over very short distances, though the faster rate should be available as the system is refined. “The main problem is with the termination. You have to have the cable very precisely aligned to get the full capacity.”