Comtech EF Data MD2401 - Manual (Page 84)

MD2401 L-Band Multi Demod Installation and Operation Manual Rear Panel Interfaces
MN-MD2401 5–4
Revision 7
5.4.6 Prioritized Queues
The MD2401 Ethernet Interface maintains four prioritized queues and uses a weighted output
scheme to insure that higher priority traffic egresses quickly, while at the same time insuring that
lower priority traffic is not stalled indefinitely. Figure 5-2 illustrates these queues, their output
weights, and the types of traffic typically assigned to those queues.
Network Queue
Voice
Network Controls
Critical Queue
Video
Controlled Load
Immediate Queue
Excellent Effort
Best Effort
Routine Queue
Bulk Traffic
8 x Output
4 x Output
2 x Output
1 x Output
Queue
Manager
Packets In Packets Out
MD2401 Prioritized Traffic Flow
Figure 5-2. MD2401 Prioritized Traffic Flow
5.5 EXT REF
The External Reference Input (J2) is supplied to allow the customer to phase-lock the
demodulator’s internal oscillator to an external reference. All internally generated frequencies
within the modem will attain the stability of the applied external reference.
This female BNC Connector accepts a 1.5 – 5 Vp-
p @ 50Ω. The frequency range of the external
reference is 1 – 10 MHz in 8 kHz steps.
5.6 SERIAL CONTROL & AGC Monitor (J3)
The Serial Control Interface Port (J3) is used for remote monitor and control utilizing Radyne's
RLLP Protocol. It offers a direct single connection to the individual demodulator. It is a Female
25-Pin D-Sub Connector supporting RS-232 or RS-485. Refer to Table 5-2A for Remote
interface pinouts and Table 5-2B for AGC Monitor pinouts.
For multi-drop communications, it is recommended that the J5 be used. The J5 connector multi-
drops all Remote ports connections allowing the user to connect to a single port. Refer to section
5.6 for additional information.