Comtech EF Data CDM-625A - Manual (Page 137)

CDM-625A Advanced Satellite Modem MN-CDM625A
Front Panel Operation Revision 3
6–11
Available Framing Types are:
FRAMING TYPE COMMENTS
► None ---
► IBS (FAST option) ---
► IDR (FAST option) ---
► D&Is (Drop & Insert) (FAST option)
which includes:
• D&I (FAST option) The D&I (Drop and Insert) multiplexer works in conjunction with the
G.703 interfaces to enable the modem to transmit or receive fractional
parts of a T1 or E1 data stream.
• D&I++ (FAST option) D&I++ is a Comtech EF Data proprietary framing – it is a closed-
network frame structure similar to D&I, but which permits AUPC and
EDMAC. See Appendix E. CLOCK MODES and DROP & INSERT
(D&I) for further information.
• QDI (Quad Drop & Insert)
(FAST option)
QDI is a variant of D&I that allows use of up to four E1 terrestrial
ports.
• Framed QDI (FAST option) Framed QDI is a concatenation of QDI and EDMAC framing.
• D&I Enhanced Available in E1-CCS; this allows enabling of ESC, and then AUPC.
► EDMACs which include:
• EDMAC EDMAC is a Comtech EF Data proprietary framing. It is backwards
compatible with the CDM-500, CDM-550, CDM-550T, CDM-600 and
CDM-600L. The framing permits bi-directional passing of M&C and
AUPC (Automatic Uplink Power Control) data between local and
distant-end units.
• EDMAC-2
(as in the CDM-570)
EDMAC-2 is a reduced overhead version of EDMAC, and is not
completely backwards compatible with the modems listed above, but
is in some modes (e.g., in Turbo BPSK modes and at rates above
2.048 Mbps). See Appendix H. EDMAC CHANNEL for further
information.
• EDMAC-3 EDMAC-3 uses the same overhead as EDMAC framing, but the
EDMAC channel operates at 1/3 the rate of original EDMAC. Most of
the overhead is dedicated to carrying the remote modem’s complete
status information (including AUPC) to the near-end modem very
quickly. Tailored to SNMP proxy applications. See Appendix H.
EDMAC CHANNEL for further information.
► ESC++ ESC++ is Comtech EF Data proprietary framing – it is a closed-
network frame structure that permits AUPC, EDMAC and ESC. See
Appendix J. ESC++ for further information.