I know I know, before we admit that CDMA2000 is not backward compatible with IS-95, we can't call ourselves knowing anything.
I tend not to make investment decisions based on technology.
I've found the source of my apprehension about CDMA2000 backward compatibility. I have a tutorial that states that CDMA2000 channels are a superset of IS-95 channels, but then it goes on to show a table that indicates that three channels found in IS-95 are not found in 3xRTT. Since the term CDMA is applied to both 1xRTT and 3xRTT, I guess I'll need to find a better source.
Get this, there're two type s of data in IS-95, packet data and Async data. Packet data will be routed onto internet from BS directly. It doesn't need your funny SGSN/GGSN type of add on.
Maybe you should get a copy of some of the CDMA2000 standards, cause all the ones I can find show a PDSN right where the SGSN/GGSN of the UMTS model sit. Circuit switched data goes through the MSC and packet data through the PDSN. I believe even the interface between the RN and PDSN is defined as part of the CDMA2000 standards.
Do you even know what is the so called VoIP? Geeze. (hint, tell me what layer it should be in).
VoIP is, like IP, a bad idea that isn't going away. Do you mean do I know that IP is, roughly, an OSI layer 3 protocol and things like CDMA and TDMA tend to fall into layer 2? |
