FTTx

Last update 7 December 2014

FTTC - Fibre To The Cabinet, FTTH/FTTP - Fibre To The Home/Premises.

FTTC involves BT Openreach installing a new street cabinet near to the existing one and linking the two. They run optical fibre from the exchange to the new cabinet then link individual lines from the old cabinet to the new one and back to get VDSL2 onto the copper connection to the premises. The PSTN phone connection continues to operate over the pre-existing cable from the old cabinet to the exchange.  It does not get put onto the fibre connection.

In other words the linkage is Exchange >> Old >> DSLAM in New >> Old >> Premises. (Traffic in both directions of course!)

On some exchanges not all existing cabinets are having new fibre cabinets attached, so FTTx enablement of an exchange does not guarantee any particular location will get it.

The initial FTTC street cabinets can handle only 288 connections each.

To estimate your FTTC speed use this graph with the sum of the copper distance from you to your cabinet and the copper distance between the two cabinets. The estimates BT give have increased, but are still very conservative.

Importantly, nothing happens to existing lines when FTTC is enabled at the exchange, until the user orders an FTTC broadband product. Existing broadband continues to run over the pre-existing cable just like the phone service above.

FTTC NTE5At the moment FTTC connections are installed by Openreach including the modem. An ethernet socket is provided for the user to access the service.

At the exchange the handover from Openreach is again by ethernet, and can be to BT Wholesale or any other (LLU) supplier present at that exchange.

Samknows, see the Useful Links page, has an FTTC status field under BT Wholesale information.

GEA - Openreach Generic Ethernet Access. This is the Openreach name for the ethernet handover method of the user’s FTTC connection to an ISP/wholesaler at the exchange, linking into a DSLAM/MSAN.

You may see VULA mentioned. According to an Openreach  document this is just OfCom’s name for GEA. Helpful - not!

BT Wholesale connect using GEA and route the traffic into their existing WBC backhaul. Note that a user’s FTTC connection may not be to the same exchange as their phone connection, so the fact their exchange is not WBC enabled does not mean they cannot get FTTC. If in doubt use the BT Wholesale availability checker.

Note that there is a Dynamic Line Management (DLM) system on Openreach FTTC, but this is not the BT Wholesale one, for the simple reason the DSLAM is in the cabinet and belongs to Openreach.  It seems to be much better than the BT Wholesale one, which is however having major revisions trialled.

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