On Wednesday, June 19, 2002, at 08:35 , Ken Chang wrote:
> I failed to find the docs, would you please give more details?
My apologies, I somehow cut and pasted the wrong stuff and that turned
out to be complete nonsense coordinates. Here is the proper URL that
should lead you directly to the document
http://l2.espacenet.com/espacenet/viewer?PN=WO0195655&CY=ep&LG=en&DB=EPD
> call forward:
>
> in GSM, people used to have to have calls routed via the trunks
> in the home network of a roaming subscriber, while the guy be
> right on another platform of the same station.
Yes, that is a call delivery via MSRN (Mobile station roaming number).
The MSRN is volatile, it as an internal signaling address that is issued
by the servicing VLR in the visited network when asked by the home
network's HLR as it is trying to find the mobile station.
> how does Zebra do optimized routing?
ZEBRA invokes a plain vanilla call forwarding service which is based on
a diallable phone number (the temporary phone number assigned and issued
by the visited network).
That call forwarding service is likely to benefit from least cost
routing which is employed by most long distance services today.
So, as far as the home network is concerned, there is no call delivery
to the mobile station, but instead there is a call forward to an
ordinary phone number (probably invoking an international call).
For the visited network this is just another incoming call to a mobile
phone in their network using the same process that is employed to
deliver a call to a local subscriber.
If the forwarding network uses LCR on their GMSC or has made
arrangements for the forwarded leg of the call to be handled by a long
distance transit network that uses LCR, then the call is routed
optimally.
The route would look like this ...
caller --> HPLMN GMSC --> Call Forward --> PSTN transit network
PSTN transit network --> VPLMN GMSC --> servicing MSC --> called party
regards
benjamin
Received on Wed Jun 19 15:31:24 2002