In computer networking and telecommunication, a frame is a digital data transmission unit that includes frame synchronization, i.e. a sequence of bits or symbols making it possible for the receiver to detect the beginning and end of the packet in the stream of symbols or bits. If a receiver is connected to the system in the middle of a frame transmission, it ignores the data until it detects a new frame synchronization sequence.
In computer networking, a frame is a data packet on the Layer 2 of the OSI model. A frame is "the unit of transmission in a link layer protocol, and consists of a link-layer header followed by a packet." Examples are Ethernet frames (maximum 1500 byte plus overhead), PPP frames and V.42 modem frames.
In telecommunications, specifically time-division multiplex (TDM) and time-division multiple access (TDMA), a frame is a cyclically repeated data block that consists of a fixed number of time slots, one for each logical TDM channel or TDMA transmitter. In this context, a frame is typically an entity at the physical layer. TDM application examples are SONET/SDH and the ISDN circuit switched B-channel. TDMA examples are the 2G and 3G circuit switched cellular voice services. The frame is also an entity for time-division duplex, where the mobile terminal may transmit during some timeslots and receive during others.
Famous quotes containing the word frame:
“The heroes and discoverers have found true more than was previously believed, only when they were expecting and dreaming of something more than their contemporaries dreamed of, or even themselves discovered, that is, when they were in a frame of mind fitted to behold the truth. Referred to the world’s standard, they are always insane. Even savages have indirectly surmised as much.”
—Henry David Thoreau (1817–1862)