T3 is the physical layer protocol used by the Digital Signal level 3 (DS3) multiplexing method in North America. A T3 interface operates at a bit rate of 44.736 Mbps. The JUNOS software supports payload scrambling and subrate operation on each physical T3 interface. One encapsulation format—Point-to-Point Protocol (PPP), Frame Relay, or High-level Data Link Control (HDLC)—must be configured for the interface. DS3 standards supported include:
To configure T3-specific physical interface properties, include the t3-options statement at the [edit interfaces interface-name] hierarchy level:
- [edit interfaces interface-name]
-
t3-options {
-
bert-algorithm algorithm;
-
bert-error-rate rate;
-
bert-period seconds;
- (cbit-parity | no-cbit-parity);
-
compatibility-mode (adtran | digital-link
| kentrox | larscom | verilink) <subrate value>;
-
fcs (16 | 32);
- (feac-loop-respond | no-feac-loop-respond);
-
idle-cycle-flag value;
- (long-buildout | no-long-buildout);
- (loop-timing | no-loop-timing);
-
loopback (local | payload | remote);
- (payload-scrambler | no-payload-scrambler);
-
start-end-flag value;
- }
You can configure the following T3 interface-specific properties: