Troubleshooting guide
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Cisco PGW 2200 Softswitch Release 9.8 Operations, Maintenance, and Troubleshooting Guide
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Chapter 3 Cisco PGW 2200 Softswitch Platform Operations
Regular Operations
For example, to re-enter the 10th-most-recently entered MML command, enter the following command:
r::10
The system returns a response appropriate to the previously entered command.
Note You can also use the up arrow key to re-execute a previously entered MML command.
Retrieving Active MML Sessions
To retrieve information on the active MML sessions, log in to the active Cisco PGW 2200 Softswitch,
start an MML session, and enter the rtrv-mml command.
The system returns a response like the following:
Media Gateway Controller - MGC-01 2008-10-17 04:37:17.586 EDT
M RTRV
mml1: mgcusr
The response lists the session number (mml1 in the example) and the user ID of the session owner
(mgcusr in the example).
Ending an MML Session
Use the quit MML command to end your current MML session.
Managing Signaling Channels
Signaling channels are bidirectional transport mechanisms for call-control signaling between the Cisco
PGW 2200 Softswitch and other devices, such as the Cisco ITP-Ls, that provide necessary delivery
reliability for higher-layer protocols. All types of signaling channels have basically the same
functionality and are managed similarly. Unless otherwise noted, all commands, counters, and alarms
apply to all types of signaling channels.
The basic types of signaling channels on the Cisco PGW 2200 Softswitch are:
• SS7 Message Transfer Part (MTP)—Used for reliable delivery. MTP level 2 provides point-to-point
delivery. MTP level 3 maintains multiple load-sharing links and multiple routes between SS7 point
codes.
• SS7 MTP over IP (SS7/IP)—MTP level 2 is terminated on the Cisco ITP-L. MTP level 3 is
backhauled to the Cisco PGW 2200 Softswitch with the Reliable User Datagram Protocol (RUDP)
that is proprietary to Cisco.
• Facility Associated Signaling (FAS)—Found in ISDN PRI or DPNSS over a 64-Kbps channel. Some
form of Link Access Protocol (LAP), for example Q.921, provides reliable delivery.
• FAS over IP (FAS/IP)—Same as FAS, but uses IP as its transport mechanism. Q.921 LAPD or
RUDP/SM provides reliable delivery.
• Media Gateway Control Protocol (MGCP)—Signaling channel, which uses UDP/IP, provides
reliable delivery.
The following sections describe the information that the system returns when you retrieve signaling
channel data using MML commands.