Identifying which mobile network your calling

bbb_uk

Heinz wrote:

Yes thanks (but I give up anyway).

Don't blame you.

Orange were the only network that said they preferred to have a database that could be updatable so they each didn't have to pay for calls they have to forward on to another network due porting numbers. I read that countries in Europe have a database that is updatable to avoid charges incurred for forwarding calls on but oftel and other 3 networks disagreed and said it wasn't necessary.

Steve_xx

bbb_uk wrote:

I believe they do this anyhow simply because of the way the porting works and how the corresponding charges work.

I explained on sayno recently here which may help explain how it works but basically each network must keep a record of any number that was on their network that has now ported. This is why BT has no idea which network you are calling (assuming it's been ported) hence reason why BT charge for the call as if it was on the network it was originally allocated to.

BT will utimately know which network they pass any call originated on their own to, due to the fact that the terminating network will bill BT for terminating the call. Therefore it would be possible for BT to calculate the true rate for its own subscriber. BT chooses not to do this, perhaps because they don't want to further confuse their customers,

grumpyoldgit_2

Jeez does anyone here speak english?

GoG

bunking_off

The current UK solution routes calls via the donor network, ie the network that hosted the number in the first place. Currently, only the donor network and the recipient network (network that now provides service) know that the number is ported. As such, an earlier poster is correct : if you port a number from Orange to Vodafone, another caller on Orange will be charged the off-net rate, regardless of the number range, because Orange will know the number's ported. However, callers on any other network will be charged the rate for calls to Orange, because as far as other originating networks are concerned, Orange have terminated the call.

Steve_xx, I'm afraid you're wrong - many networks interconnect directly and providers only use BT when they have to. In this ported scenario, a call originated on BT would route to Orange then Voda, and BT would have no visibility of the second leg hence does not have the information to bill differentially.

I seem to remember that recent changes to the mobile number portability spec allow mobiles in particular to look ahead on the routing, so the e.g. a call from 02 to the ported number could conceivably be routed directly to Voda and miss out Orange...in this situation 02 might bill differentially on a retail level. However, I'm not aware of any mobile operator actually implementing that option.

The alternative to the UK number portability solution is to have a central database that all operators query before routing calls. Independent analysis has been done by Ofcom that proves this less efficient : in brief, the cost of doing the lookup for the calls to 90%+ of numbers that aren't ported outweighs the benefit of the more efficient routing for the <10% of numbers that are ported. It worked out the overall cost would be >£100M. However, all networks are currently migrating to "next generation" technologies, based on internet protocol, and the standards bodies are looking at whether these economics still hold true.

gizmoleeds

Also, as all networks I am aware of just have a standard "other network" charge it doesn't really matter if Orange know whether or not your number has been ported from O2 to T-Mobile as the cost would be the same regardless as it is another network.

BT do charge different rates to different networks, but the differences are so minor that it is really irrelevent.

bbb_uk

bunking_off wrote:

The current UK solution routes calls via the donor network, ie the network that hosted the number in the first place. Currently, only the donor network and the recipient network (network that now provides service) know that the number is ported. As such, an earlier poster is correct : if you port a number from Orange to Vodafone, another caller on Orange will be charged the off-net rate, regardless of the number range, because Orange will know the number's ported. However, callers on any other network will be charged the rate for calls to Orange, because as far as other originating networks are concerned, Orange have terminated the call...

When a number has been ported through most if not all the networks does the call get forwarded through each one in turn until it finally ends up at its destination?

Eg. A mobile was originally allocated to Voda but since then has been ported to T-Mobile and Orange and it is now on o2. Now if someone from a landline or Orange, etc ring this number then is the call is routed to o2 via Voda, T-Mobile and Orange?

gizmoleeds

bbb_uk wrote:

When a number has been ported through most if not all the networks does the call get forwarded through each one in turn until it finally ends up at its destination?

Eg. A mobile was originally allocated to Voda but since then has been ported to T-Mobile and Orange and it is now on o2. Now if someone from a landline or Orange, etc ring this number then is the call is routed to o2 via Voda, T-Mobile and Orange?

I imagine when this happens they just inform the original operator to route the call to the new one, however it is not beyond the realms of possibility.

bunking_off

bbb_uk wrote:

When a number has been ported through most if not all the networks does the call get forwarded through each one in turn until it finally ends up at its destination?

Eg. A mobile was originally allocated to Voda but since then has been ported to T-Mobile and Orange and it is now on o2. Now if someone from a landline or Orange, etc ring this number then is the call is routed to o2 via Voda, T-Mobile and Orange?

That's called "subsequent portability". It becomes a 3-way exercise - the rangeholder removes the data that would route the call to recipient_network1 and changes it so that the call routes to recipeint_network2. So, in your example, the call would route to Vodafone then straight to o2 - T-Mobile & Orange would not be involved in the call.

Therefore, you don't get the sort of convoluted call paths that you describe.

Where you do end up with such situations is where someone has an 08 number that they port from one operator to another, which is pointing to a geographic number that's been ported from one operator to another. The call goes through the donor network for the 08 then recipient for 08 then donor for geo then recipient for geo. For customers that generate high traffic volumes (e.g. anything published on TV) we'd put special measures in the network to stop that happening.

NB on all of this, it's a technical nuance, but the calls aren't "forwarded" in the context of the user type functionality for diverting calls...it's done deep in the network configuration.