llmarinen: About GPRS and WAP Neither one is really anything without the other, this is a must to consider when thinking about either one
From the air interface standpoint, WAP makes use of an existing GSM control channel called Stand Alone Dedicated Control Channel (SDCCH), the same channel incidentally is used for GSM call setup. SDCCH's are also used as bearers for SMS. From an implementation standpoint, no new air interface hardware is required. A wap server and a few hundred hours of configuration and programming and voila, you have Le Wap.
GPRS on the other hand, is a different kettle of fish. For one, all base stations must be upgraded with packet control cards and in fact, the air interface channel used is the same used in GSM for voice. Then there are serious fixed IP infrastructure costs with at least 2 gateway serving nodes per GPRS operator.
In the former case, you can accomodate WAP and SMS by stealing a few setup channels from the pool normally available for voice. Normally not a huge redimensioning effort. For the latter, you have to totally revisit your cost model as you will be shifting high return voice channels to less profitable IP traffic.
So IMO, WAP and GPRS are really quite seperate entities. You can have both, none or either one. |
