BGP Communities

Inbound routes are all tagged with an informational community by Simwood (AS42353), generally to indicate origin.
 

Geographical (i.e. point of connection to source)

42353:1XXX - London
42353:2XXX - Manchester
42353:3XXX - Edinburgh
42353:4XXX - Slough

where XXX describes the origin in more detail as below.

Route type

42353:X000 - Simwood full transit customer
42353:X050 - Simwood partial transit customer
42353:X100 - Private peer
42353:X200-250 - Peering exchange. Specifically:
      42353:1200 - LONAP
      42353:1250 - LINX Juniper LAN (Telehouse East)
      42353:2200 - IXManchester
      42353:2250 - AMS-IX
      42353:4250 - LINX Juniper LAN (Equinix LD4)
42353:X300 - Bought partial transit
42353:X400 - Bought full transit

 where X signifies the site as above.

 Examples

42353:3000 - Simwood full transit customer connecting in Edinburgh
42353:2400 - Route learned over full transit egressing in Manchester
42353:1100 - Private peer in London