Comtech EF Data DMD50 Installation And Operation Manual page 255

DMD50 Universal Satellite Modem
X = Truncation of (1200 / (5 * 125)
X = Truncation of (1.92)
X = 1
Add 1 * 5 * 125 bps to our previous calculation gives 331875 bps
An increase of 625 bps to carry 1200 baud
Example 2a:
10 Drop Slots with T1-D4 framing, standard ES to ES overhead
For 10 Drop Slots, the Data Rate would be 10 * 64000 or 640000 bps
The Efficient D&I Rate would be 640000 + (10 * 250) bps = 642500 bps
The Drop & Insert Open Network rate is over 40,000 bps higher at 682667 bps.
Example 2b:
Change to E1-PCM30 framing (E1 Signaling), standard ES to ES overhead
Add 10 * 2000 bps to our previous calculation gives 662500 bps
Still saving over 20,000 bps compared to the Drop & Insert open network standard.
Example 2c:
Change to Enhanced Async with In-Band Baud Rate of 1200
X = Truncation of (1200 / (10 * 125)
X = Truncation of (0.96)
X = 0
The rate stays at the previous value of 662500
With 10 slots, there is no increase required to carry 1200 baud Enhanced Async. It is passed
transparently in the Efficient Drop & Insert overhead.
MN-DMD50– Revision 3
Efficient Drop and Insert (D&I)
I–5