 1992b), Batch file transfer the layers being described in the next section. Light 1 5 secs 1 30 secs 32kbit/s The application areas of DECT are somewhat wider than those identified in Section 49.3. For example the system is expected to Heavy 1 30 secs 5 1000 secs 64kbit/s support radio access to office voice and data networks at informa- Real time file access tion bit rates considerably in excess of the 32kbit/s foreseen for speech transmission. Indeed data transmission has figured signifi- Slices 200ms 2 64 256kbit/s cantly in the preparation of the specification. DECT, therefore, offers bearers that are well matched to the needs of teleservices. Chunks 500ms 1 10 secs 64 256kbit/s For ISDN-based applications a continuous 144kbit/s full duplex bearer is available. Even this is not sufficient for other uses associ- ated with data transmission in real time and/or short bursts. Such opment that the technology can also be used as an access technology requirements are indicated in Table 49.1 (ETSI, 1992b). For data to other communication networks both public and private. For applications, variable transaction times 100ms to 10 seconds are example, provision has been made in the design of DECT to enable anticipated and transmission is anticipated to be predominantly one it to be developed as another access technique able to use the GSM way. Fast link establishment time, under 50ms (not including Port- digital cellular fixed network. This means that DECT must in due able Part verification) is required. Variable rate communications is course be able to access and use the roaming and location intel- required. Note that these applications demand rapid access to bearer channel and since radio channels must be released between bursts ligence built in to the GSM system. Similar provisions are being of information (to conserve spectrum for other users) then the result made to ensure the capability to interwork with evolving public is a requirement for rapid radio channel acquisition algorithms intelligent telecommunication n