What is Temporary Block Flow?

Question

It would be nice if someone can explain why do we need it ?

Answer 1

Very easy question. Probably the first link if you open the Google. What is Temporary Block Flow.

• General Packet Radio Service (GPRS) is a mobile data service in Global System for Mobile Communications (GSM) protocol networks.
• Temporary Block Flow (TBF) is a connection established between a Mobile Station (MS) and a Base Station (BS) to enable packet exchanges between the BS and MS entities in GPRS networks.
• The current TBF handling in GPRS is based upon burst traffic models, such as Web surfing and email transfer.
• TBF setup is initiated upon buffering a packet for transmission in the MS.
• In GPRS, TBF set-up is performed on a random access channel (RACH) and requires some time.
• The TBF set-up delay however adversely affects the performance of some real-time applications such as Voice over Internet Protocol (VoIP) among other delay sensitive applications.
• TBF is released when all buffered packets are de-queued before the arrival of the next packet.
• This release mechanism may result in frequent TBF re-establishments and associated delays for some applications, for example, in VoIP applications, which include a sequence of packets containing voice frames are regularly separated by an inter-arrival time within a talk spurt illustrated in FIG. 1. Frequent TBF setup/release events may also unnecessarily increase signaling overhead.
• A Temporary Block Flow (TBF) is a logical connection used by two General Packet Radio Service (GPRS) entities to support the unidirectional transfer of lower layer compatibility (LLC) and protocol data units (PDUs) on packet data physical channels (PDCHs)(or timeslots).
• In a typical GPRS system, the network needs to establish a downlink (DL) TBF to transfer data in the DL direction and an uplink (UL) TBF to transfer data in the UL direction. TBFs are typically short-lived and are generally only active during data transfers. i.e. until there are no more RLC (Radio Link Control) / MAC (Medium Access Control) blocks to be transmitted.