25. High-Level Data Link Control Procedures--Frame Structure, ISO 3309, International Standards
Organization, Geneva, 1979.
26. Military Communication System Technical Standard, MIL-STD-188C, US Department of
Defense, Washington, DC, 1966.
27. Reference Data for Engineers: Radio, Computers and Communications, 8th edition, SAM Pub-
lishing, Carmel, IN, 1993.
28. A Digital Modem and Analog Modem Pair for Use on the Public Switched Telephone Network
(PSTN) at Data Signaling Rates of up to 56,000 bits/s downstream and up to 33,600 bits/s
Upstream, ITU-T Rec. V.90, ITU Geneva, 1998.
29. A Digital Modem Operating at Data Signaling Rates up to 64,000 bits/s for Use on a 4-wire
Circuit Switched Connection and on Leased Point-to-point 4-wire Digital Circuit, ITU-T Rec.
V.91, ITU-Geneva, May 1999.
30. List of Definitions for Interchange Circuits Between Data Terminal Equipment (DTE) and Data
Circuit-Terminating Equipment (DCE), ITU-T Rec. V.24, ITU Geneva, 2000.