Glossary
V.54: The
•local digital loopback (tests DTE send and receive circuits),
•local analog loopback (tests local modem operation),
•remote analog loopback (tests comm link to the remote modem), and
•remote digital loopback (tests remote modem operation).
Virtual Circuit: A logical connection. Used in packet switching wherein a logical connection is established between two devices at the start of transmission. All information packets follow the same route and arrive in sequence (but do not necessarily carry a complete address).