mikeliuk
ULTIMATE Member
Do all UK service providers use Trombone Roaming, at least for packet data?
Recently in California, I was surprised to see EE packet data routed via the UK as I don't believe I've seen this with Three UK or Virgin Mobile when roaming before.
What I was expecting was Roaming onto the local carrier network (services provided locally and billing/usage details forwarded to my supplier) per the below reference, and not Trombone Roaming as mentioned right at the end of the page.
Routing packet data via the UK could be one reason that EE's costs compare well to other UK service providers but at the disadvantage is that the full benefit of the Roaming onto local infrastructure is not realized due to tromboning increasing latencies beyond what is acceptable for some applications.
I guess I should provide some explanation of why trombone roaming might be a bad idea. You might be in the US communicating with a server in the US and international packet links are very expensive and in constraint, therefore you don't want to send data to the UK which does not need to go to the UK, and worse than that the unnecessary data traffic to the UK then needs to come back across an international link to arrive at an endpoint very near the source of the data.
en.wikipedia.org
Recently in California, I was surprised to see EE packet data routed via the UK as I don't believe I've seen this with Three UK or Virgin Mobile when roaming before.
What I was expecting was Roaming onto the local carrier network (services provided locally and billing/usage details forwarded to my supplier) per the below reference, and not Trombone Roaming as mentioned right at the end of the page.
Routing packet data via the UK could be one reason that EE's costs compare well to other UK service providers but at the disadvantage is that the full benefit of the Roaming onto local infrastructure is not realized due to tromboning increasing latencies beyond what is acceptable for some applications.
I guess I should provide some explanation of why trombone roaming might be a bad idea. You might be in the US communicating with a server in the US and international packet links are very expensive and in constraint, therefore you don't want to send data to the UK which does not need to go to the UK, and worse than that the unnecessary data traffic to the UK then needs to come back across an international link to arrive at an endpoint very near the source of the data.
Roaming - Wikipedia
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