Juniper Networks M20 manual E1 PIC

M20 Internet Router PIC Guide

E1 PIC

Software release	■	JUNOS 4.1 and later
Description	■	Four E1 or coaxial ports
	■ Power requirement: 0.08 A @ 48 V (3.74 W)
	■	Two versions:
		■	4-port, 120-ohm, RJ-48
		■	4-port, 75-ohm, coaxial
	■ Onboard DSU functionality for E1 connectivity
Hardware features	■	High-performance throughput on each port at speeds up to 2.048 Mbps, full duplex
	■ Maximum transmission units (MTUs) of up to 4500 bytes
	■ Per-interface diagnostics and loopback control
	■ Per-interface shaping on output
	■ Per-interface alarm and event counting and detection
	■	HDB3 line coding
	■ 4-bit CRC for G.704 framed mode
	■ Per-port loop timing
	■ Balanced and unbalanced modes
	■ Packet buffering, Layer 2 parsing
	■ Full bit error rate test (BERT)
Software features	■	Integrated support for G.703 unframed mode and G.704 framed mode with CRC; this
		feature is user-configurable
	NOTE: The G.704 implementation supports speeds slower than 2.048 Mbps; multiple channels
	within a single E1 interface are not supported.
	■ Configurable clock source: Internal or loop
	■	Encapsulations:
		■ High-Level Data Link Control (HDLC)
		■	Frame Relay

■ Circuit cross-connect (CCC) ■ Point-to-Point Protocol (PPP)

38■ E1 PIC