Relay network, measurements and sign Data-link connection identifier (DLCI) - a 10-bit field that identifies a virtual connection. Extended address (EA) - if set to 1, the current byte is the last in the DLCI (current implementations use a two-byte DLCI) Command/response (C/R) - not currently defined. more details of Relay network show in drawing for more details of Relay network, measurements and sign download this AutoCAD file, cad drawing or dwg format.