aporove

1. do you mean CS as circuit switching? if so, Usually, VLR and HLR is part of MSC but exactly it is a different system.

2. The synchronization only do once when you provisioning the subscriber database. Usually it provisioning to both HLR and AAA. I do not know how exactly GSM PS work, but in CDMA PDSN do not have access to HLR that's why it is need an AAA server to do authentication, accounting, and authorization.

3. PDSN is an access server exactly ( but yeah -- you can thing it act as switching for PS). Yeah -- you are right about the traffic flow but in best practice, home agent usually only a gateway to internet.

1. VLR who have the active subscriber data, if there are no data in VLR then VLR will request to HLR
2. Yup, AAA have all data service subscriber database
3. Because PDSN who will decide how to do with AAA message.

You are right.

Samsung is reasonable great mobile phone regarding the price.

What a great inspiring story. Yeah, we do not know what we get in future so do not judge by current situation for our fail because it may lead us to future success.
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It think it will be play big rule in future competition of telecommunication companies success. It will help telecommunication companies to plan their network and service so can make necessary step to survive.

It is because link cost to Singapore is expensive.

Yes, it similar like mini opera, but the server usually lies in brew operator it self.

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