Specifications
3 SS7MD Board-Specific Configuration and Operation
16
Note: The ss7.dc6 and ss7mcd code files are distributed as part of the Dialogic
®
DSI Development
Package. The ima.dc6 code file is available on request.
The code file requires a host license which enables the software to run on the board,
details on how to use a Host License are given in the Dialogic
®
Distributed Signaling
Interface Components Host Licensing User Guide.
3.2 Monitoring
The DSI SS7MD board can be used in conjunction with the SS7 Development Package
for the appropriate operating system (Linux, Solaris SPARC or Solaris x86) to realize a
high-performance protocol monitor with up to 4 boards, each monitoring a certain
number of links (see the table in Section 2.4.1, “Run Modes”).
In this mode the board is able to monitor many HDLC based signaling protocols
including SS7, LAPB, Q.921 (ISDN PRI) and DPNSS. The protocol should have a
minimum frame length (excluding flags) of 5 octets and a maximum of 278 octets, and
must use the CRC polynomial (x16 + x12 + x5 + 1). When operating in monitoring
mode, the 3rd and successive identical frames may be filtered.
It is possible to configure monitoring and terminated SS7 links on the same signaling
board.
For receive only operation, the board allows the T1/E1/J1 interfaces to be configured in
any of the following modes:
- Normal terminated impedance
- High impedance (not recommended for new designs)
- Protected Monitoring Point mode (preferred mode of operation for monitoring).
When using High Impedance mode care should be taken to avoid long cable runs as
this can result in poor signal quality due to signal reflections.
3.2.1 Configuration
The user needs to set up the configuration for the T1/E1/J1 interface and the operating
parameters for each link to be monitored. This can be achieved using the config.txt file
in conjunction with the s7_mgt configuration utility. Users wishing to use discrete
message-based configuration should to Section A.2, “Monitoring Configuration Using
Individual Messages”.
3.2.2 Runtime Operations
Once configured, whenever a frame is received, it is reported to the user’s application
as an API_MSG_RX_IND message.
During operation, the user may also read (and optionally reset) various statistics on a
per-link basis by sending a DVR_MSG_R_L1_STATS message.