Specifications

Chapter 1 Introduction Installation and Operation Manual
1-2 Overview ASMi-31 Ver. 3.0
Figure 1-1. Central Site Application with SNMP Management
Features
Line Interface
ASMi-31 supports full-duplex transmission of 2B+D channels over 2-wire twisted
pair unconditioned line. The line data rate is 160 kbps and the line coding is
2B1Q. This coding provides immunity to the background noise, eliminates normal
line distortion and enables efficient transmission over 2-wire twisted cables.
Using advanced adaptive echo cancellation technique, ASMi-31 supports data
transmission up to 40 dB at 40 kHz and maximum resistance of 130Ω. The
achieved typical range is up to 7 km (4.3 miles) over 24 AWG (0.4 mm) pairs with
nominal line impedance of 135Ω. ASMi-31 line interface terminates in an RJ-45
8-pin connector.
An adaptive equalizer provides noise immunity and high performance over low
quality lines.
ASMi-31 modem is coupled to the telephone lines via an isolation transformer, to
protect it against overvoltages. Additional protection against lightning surges,
power line contact and induction from power lines is provided by using special
components on both sides of the isolation transformer. Line protection complies
with the ITU K.21 requirements.
DTE Interface
ASMi-31 modem supports the following DTE interfaces: RS-530, V.24, V.35, V.36,
X.21, G.703 Codirectional (64 kbps), Ethernet bridge, Ethernet bridge with VLAN
support, and IP router.
ASMi-31 supports both asynchronous and synchronous modes of DTE operation.