A data link connection identifier (DLCI) is a channel number which is attached to frame relay
data frames to tell the network how to route the data. This 10-bit field defines the destination address of a
packet. The address is local on a link-by-link basis.
Frame relay is
statistically multiplexed, which means that only one frame can be transmitted at a time but many
logical connections can co-exist on a single physical line. The DLCI allows the data to be logically tied to one of the connections, so that once it gets to the network it knows where to send it.
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DATA LINK CONNECTION IDENTIFIER. DLCI