Troubleshooting guide
B-2
Cisco PGW 2200 Softswitch Release 9.8 Operations, Maintenance, and Troubleshooting Guide
OL-0800-14
Appendix B Troubleshooting Cisco ITP-L Signaling
Cisco ITP-L Signaling Overview
Cisco ITP-L Signaling Overview
This section contains the following subsections:
• IP Signaling Backhaul, page B-2
• Connection Management, page B-3
IP Signaling Backhaul
The Cisco PGW 2200 Softswitch and Cisco ITP-L communicate using the Reliable User Datagram
Protocol (RUDP) that is proprietary to Cisco to perform IP signaling backhaul.
You can issue the following Cisco ITP-L command line interface (CLI) command to trace backhaul
messages:
debug ss7 mtp2 backhaul
channel
The following sections describe IP signaling backhaul:
• Types of Encapsulation, page B-2
• PDU Verb Types, page B-2
• Backhaul Message IDs, page B-3
Types of Encapsulation
There are two types of data encapsulation that are associated with IP signaling backhaul messages:
• Non-PDU messages—Defined as session manager control messages. These messages serve to
control active and standby sessions with the respective Cisco PGW 2200 Softswitches.
• PDU messages—Messages the Session Manager delivers to the Message Transfer Part (MTP) Level
2 (MTP2). These messages serve to control MTP2 and to send and receive message signaling unit
(MSU) messages.
PDU Verb Types
There are three PDU verb types that are associated with IP signaling backhaul commands and messages:
• Requests—Messages that are sent only from the Cisco PGW 2200 Softswitch to the Cisco ITP-L.
These messages request the Cisco ITP-L to perform some action, such as to connect the link (align
link), disconnect the link, or to return its statistics.
• Confirmations—Messages that are sent from the Cisco ITP-L to the Cisco PGW 2200 Softswitch to
indicate that a requested action completed successfully or failed.
• Indications—Asynchronous messages that are sent from the Cisco ITP-L to the Cisco PGW 2200
Softswitch to indicate that the Cisco ITP-L detected a state change, such as link alignment lost.