ACCULINK 317x E1 DSU/CSU
1-2 March 1996 3170-A2-GB20-10
DTE Drop/Insert Interface
The DTE Drop/Insert interface is compatible with the
signal format of CCITT Recommendation G.703 and the
frame structure of CCITT Recommendation G.704. This
interface allows DTEs/PBXs to share the E1 network with
other high-speed equipment.
Alarm Message Capability
The E1 DSU/CSU can be attached, either locally or
remotely, to an ASCII terminal or printer to display or
print alarm messages. The communications (COM) port
can be used as the destination for Alarm Set and Alarm
Clear messages. This enables an ASCII terminal or printer
to monitor the E1 DSU/CSU for alarm conditions. Alarms
can also be displayed on a PC that is using a terminal
emulation package.
Front Panel Emulation
The E1 DSU/CSU offers functionality through Front
Panel Emulation software that is similar to that provided
by the E1 DSU/CSU front panel. The E1 DSU/CSU can
either be locally or remotely attached to a 386 or higher
personal computer (PC) that has at least four megabytes
(MB) of random-access memory (RAM). (An external
modem is required for remote attachment.) A copy of the
E1 DSU/CSU front panel appears on the PC. The
functionality of the front panel is available by clicking on
the function keys with the mouse rather than by pressing
keys from the actual front panel. For more information,
refer to Appendix G, Front Panel Emulation.
SNMP Management Support
SNMP is a network management protocol that is used
to monitor network performance and status, and to report
alarms (i.e., traps). To function, SNMP requires a manager
consisting of a software program housed within a
workstation or PC; an agent consisting of a software
program housed within a device (e.g., the E1 DSU/CSU);
and a Management Information Base (MIB) consisting of
a database of managed objects.
Users of the external SNMP manager can issue “Get”
and “Set” commands to an object in the SNMP database
maintained by the E1 DSU/CSU.
The E1 DSU/CSU can be managed by any industry-
standard SNMP manager. AT&T Paradyne provides an
SNMP application that runs on a Hewlett-Packard HP
OpenView network management platform. For more
information, refer to the ACCULINK 3100 Series Open
Management Application for HP OpenView User’s Guide.
The E1 DSU/CSU supports the following MIBs:
• MIB II – Defines the general objects for use in
Transmission Control Protocol/Internet Protocol
(TCP/IP) internets and provides general
information about the E1 DSU/CSU. MIB II is
backward-compatible with MIB I.
• DS1/E1 MIB – Defines objects for managing E1
interfaces and supports the network and DTE
Drop/Insert interfaces on the E1 DSU/CSU.
• RS-232-like MIB – Defines objects for managing
RS-232-type interfaces (e.g., RS-422, RS-423, etc.)
and supports synchronous data ports (PORTs 1–4)
and management communication ports (AUX and
COM ports) on the E1 DSU/CSU.
• Generic-Interface Extension MIB – An extension to
MIB II that defines additional objects for control of
generic interfaces in MIB II. It supports control of
tests on the E1 and synchronous data interfaces that
are not supported by other MIBs.
• Enterprise MIB – Defines objects that are unique to
AT&T Paradyne devices.
Two link layer protocols, Point-to-Point Protocol (PPP)
and Serial Line Internet Protocol (SLIP), are supported for
connection to an external SNMP manager or network
device (e.g., a router).
The SNMP manager or network device can be directly
connected to the communications (COM) port. An
external LAN Adapter can be connected to either the
COM port or the auxiliary (AUX) port to provide Ethernet
connectivity. Also, the E1 DSU/CSU can be daisy chained
together by connecting the COM port of one device to the
AUX port of the other, providing SNMP connectivity.
The SNMP management system can communicate to
the E1 DSU/CSU remotely through the Facility Data Link
(FDL) or the synchronous data port’s Embedded Data
Link (EDL). FDL provides an in-band channel for
performance and control signals on the network interface.
It uses the spare bit S
a4
in time-slot zero as defined in
CCITT standard G.704. EDL provides the ability to detect
and synchronize on a framing pattern, provides cyclic
redundancy checking (CRC), and maintains near-end and
far-end performance statistics.