In GSM, transmission is circuit-switched. This means that the communication path between the GSM mobile phone and the far end is occupied as long as the connection is maintained i.e. even during pauses in a conversation or in pauses during data transmission over GSM. This is basically inefficient, as data communication is normally not continuous but occurs in bursts, i.e. in the form of packets. Often the line is only utilised for one-third of the time, going to waste the rest of the time. With GPRS, on the other hand, once an Internet site has been downloaded, the network capacity used is immediately released once again. Only when data is actually being downloaded from the Internet is any network capacity used. If several channels are bundled together, the term High Speed Circuit Switched Data is used (see HSCSD).
Used by wireless carriers, this method lets a user connect to a network or the Internet by dialing in, such as with a traditional phone line. It's a dial-in Internet service provider for wireless device users. Circuit-switched connections can be slow and unreliable compared with packet-switched networks, but for now circuit-switched networks are the primary method of Internet and network access for wireless users in the United States (see Packet-switched network).
A classification for networks where the device connects to the network only when placing or receiving a call, such as with a traditional phone line. Next generation wireless networks will use packet-based networks, which are “always connected.