Dark Fibre

August 5th, 2013 by

Over the last twelve months we’ve made a series of networking changes and completely failed to blog about them. Our first announcement is that we now have a dark fibre ring around our core London sites.

This isn’t actually true. We now have a lit fibre ring around our core London sites. It’s currently running at 10Gbps and connects all of our routers together. All our routers connect to the local networks at 10Gbps so our entire network core is now 10Gbps. We also have some direct customer connections who are using our fibre as a layer 2 interlink between Telecity Sovereign House, Telecity Meridian Gate and Telecity Habour Exchange 6/7. Our standard is to offer a pair of ports in each site on redundant switches (so 6 x 1Gbps ports) with unlimited traffic between them.

As a result of our upgrade we’re able to continue to offer free traffic between all London hosted servers irrespective of the building the machines are in or which customer owns them – we bill only for traffic that leaves our network. Upgrading to progressively higher bandwidths is now straightforward as we can add CWDM / DWDM as required to increment in multiples of 10Gbits, or to 40Gbits or multiples of 40Gbits.

For those of you that are interested, the fibre lengths are

  • MER <-> SOV : 1672ns (or 1122ft)
  • SOV <-> HEX : 6423ns (or 4310ft)
  • HEX <-> MER : 5456ns (or 3687ft)

and the latencies across the network from core router to core router (average over 10 pings) are

  • MER <-> SOV : 0.096ms
  • SOV <-> HEX : 0.082ms
  • HEX <-> MER : 0.076ms

and from customer machine in SOV to customer machine in HEX, passing through at least two routers – 0.5ms.