TCP/IP PROTOCOL
November 3, 2009 by Nauman · Leave a Comment
For many years, the technical literature on protocol architectures was dominated by discussions related to OSI and to the development of protocols and services at each layer. Throughout the 1980s, the belief was widespread that OSI would come to dominate commercially, both over architectures such as IBM’s SNA, as well as over competing multivendor schemes [...]
Global System for Mobile Communications (GSM)
November 3, 2009 by Nauman · Leave a Comment
•Designed to be a digital (wide area) wireless network. • Driven by European telecom manufacturers, operators, and standardization committees • Very widely used around the world GSM Features 1.Service portability • Mobile can be used in any of the participating countries with international roaming and standardized numbering & dialing (but possibly at different rates!) • [...]
Cellular Digital Packet Data (CDPD)
November 3, 2009 by Nauman · Leave a Comment
In 1992, AT&T Wireless Services developed cellular digital packet data (CDPD) protocol, a data-only protocol that (re-)uses the AMPS or IS-136 network. Packets (typically some 1.5 kilobytes) use vacant cellular channels – either an assigned channel or between calls. CDPD does not communicate with the underlying network (but does utilize knowledge of this networks channel [...]