ADTRAN Express L768 - Manual (Page 34)

Chapter 2. Installation
2-2 Express L768 User Manual 61203192L1-20
SDSL Overview
A new technology has been developed for the telcos for delivery of T1
service. The technology is known as high-bit-rate digital subscriber
line (HDSL). HDSL employs a 2B1Q modulation technique across the
same types of pairs traditionally encountered with metallic T1 deliv-
ery systems. HDSL satisfies the telco distance requirements without
the use of repeaters.
Symmetric Digital Subscriber Loop (SDSL) is HDSL using only one
pair. This provides a maximum of 768 kbits/sec, which is half the rate
of HDSL.
LOCAL AREA NETWORK CONNECTION
The Express L768 has a 10BaseT connector that provides half-duplex
10 Mbps operation over a four-wire twisted pair. Place the switch in
the TO HUB position when connecting to a 10BaseT concentrator or
Hub. Place the switch in the TO NIC position when connecting direct-
ly to a computer’s 10BaseT network interface card.
Other types of ethernet interfaces (i.e., AUI, 10Base2, etc.) can be ac-
commodated by obtaining an appropriate converter.