Troubleshooting guide

1-6
Cisco PGW 2200 Softswitch Release 9.8 Operations, Maintenance, and Troubleshooting Guide
OL-0800-14
Chapter 1 Cisco PGW 2200 Softswitch Platform Overview
Cisco PGW 2200 Softswitch Software Architecture
Input/Output Subsystem
The I/O subsystem consists of the I/O channel controllers (IOCC) and the I/O channel manager (IOCM),
which manages the controllers.
• IOCM manages all IOCCs.
• IOCCs provide:
– Protocol-specific, message-based interface that allows nodes and platforms that are external to
the Cisco PGW 2200 Softswitch to communicate with the Cisco PGW 2200 Softswitch.
– Interface that allows buffering of messages to the call engine event dispatcher queue.
• The Cisco PGW 2200 Softswitch software I/O subsystem includes the following IOCCs:
– Basic Rate Interface (BRI)—Added in Release 9.5, this IOCC enables the backhaul of Layer 3
QSIG and Q.931 messages in a TCP session. This IOCC operates between a Cisco PGW 2200
Softswitch and voice gateways that support BRI signaling backhaul.
– Digital Private Network Signaling System (DPNSS)—Added in Release 9.4, this IOCC enables
the transparent transport of DPNSS data over IP. This IOCC operates between media gateways
that support DPNSS.
– Extended ISDN User Part (E-ISUP)—Protocol proprietary to Cisco that enables the transport
of endpoint information and media-gateway-specific information between two (or more) Cisco
PGW 2200 Softswitches. This protocol provides an enhanced ISUP base to support all ANSI
and ITU ISUP messaging and elements. It also has additional fields to support the transport of
service information (such as local number portability [LNP], 800 numbers, and so on).
– ISDN Level 3—Provides backhauling of ISDN (standard variants) from a media gateway to a
Cisco PGW 2200 Softswitch.
– ISDN Q.921 User Adaptation Layer (IUA)—Added in Release 9.4, this IOCC enables
backhauling of ISDN Q.921 user messages over IP with the Stream Controlled Transmission
Protocol (SCTP). This IOCC operates between a Cisco PGW 2200 Softswitch and media
gateways.
– Media Gateway Control Protocol (MGCP)—Enables communication with media gateways and
trunking gateways. This protocol enables you to set up and configure bearer channel
connections on the Cisco PGW 2200 Softswitch for call control environments.
– Message Transfer Part Level 3 (MTP3) User Adaptation (M3UA)—Added in Release 9.4, this
IOCC enables the transport of any SS7 MTP Level 3 User signaling (for example, ISUP and
TUP messages) over IP with SCTP. This IOCC operates between a Cisco PGW 2200 Softswitch
and a Cisco IP Transfer Point (ITP).
– Q.931+—A stateless IOCC, for a protocol proprietary to Cisco, which is a special version of
ISDN that enables forward hauling of Q931+ signaling to a media gateway. You configure this
IOCC on a Cisco PGW 2200 Softswitch for signaling environments.
– Session Initiation Protocol (SIP)—Enables the Cisco PGW 2200 Softswitch to receive and send
SIP messages over the User Datagram Protocol (UDP).
– Signaling Control Connection Part (SCCP) User Adaptation (SUA)—Added in Release 9.4, this
IOCC enables the transport of any SCCP user signaling (for example, TCAP messages) over IP
with SCTP. This IOCC operates between a Cisco PGW 2200 Softswitch and a Cisco ITP.
– Signaling System 7 (SS7)—Contains MTP3, which backhauls SS7 signaling from a Cisco IP
Transfer Point LinkExtender (ITP-L) to the Cisco PGW 2200 Softswitch.