The protocol bit...
The "protocol bit" , I believe means Infrastructure (equipment)
that is built to comply with certain GSM rules or standards.
Please correct me if I am wrong.
Not just the infra bit. The handset, The basestation and message switching centre software conform to a 'layered' specification.
Each layer has well defined responsibilities.
For example, consider the handset. For voice, the top layer (L3) would be the network layer. This is responsible for Call control, mobility management etc. L2, the Data Link Control layer, is responsible for delivering error free data to L3. L1 is the Physical
Layer, responsible for acquiring frames from the air interface andpassing them to Layer 2.
L1 and the air interface(i.e. how the signals are modulated ) is what people are really talking about when they talk about CDMA, GSM, AMPS et al. The QCOM/Vodafone experiment in the UK swapped out the GSM air interface for a CDMA one.
An aside, the IS-95 protocol stack, is based on AMPS.
w. |
