This MIB is an enhancement for existing XGCP-MIB.
xGCP is a set of protocols, for example SGCP (Simple
Gateway Control Protocol) and MGCP (Media Gateway
Control Protocol), which are designed as a control
protocol within a distributed system that appears
to the outside as a single VoIP/VoATM gateway.
This system is composed of a call agent (or MGC,
Media Gateway Controller) and of a set of
'media gateways' that perform the conversion of media
signals between circuits and packets.
In the xGCP model, the gateways focus on the audio signal
translation function, while the call agent handles the
signaling and call processing functions.
Examples of Gateway Control Protocols are:
* Simple Gateway Control Protocol (SGCP)
* Media Gateway Control Protocol (MGCP)
xGCP assumes a connection model where the basic constructs are:
Endpoints : sources or sinks of data that could be physical
Connections : an association between two or more endpoints
with the purpose of transmitting data between
Once this association is established for both
endpoints, data transfer between these
endpoints can take place.
Connections are grouped in calls. One or more connections
can belong to one call. Connections and calls are set up at
the initiative of one or several call agents.
AAL : ATM Adaptation Layer
AUCX : Audit Connection Command used by the MGC to find out
the status of a given gateway connection.
AUEP : Audit Endpoint Command used by the MGC to find out the
status of a given endpoint.
CCAPI : Call Control Application Program Interface.
CID : Channel Identifier
CRCX : Connection Command from a MGC to request the
MG : Media Gateway
MGC : Media Gateway Controller
DLCX : Delete Command. This command can be initiated by
either the MGC or gateway.
GSM : Global System for Mobile Communications
GW : Gateway.
HP : Hairpin
MDCX : Modify Connection Command from a MGC to request the
NSE : Negative Stuffing Event
NTFY : A Notify Command sent from a gateway to a MGC in
response to a RQNT command.
PSTN : Public Switched Telephone Network
RQNT : Request To Nofity Command from a MGC to request the
gateway to provide a notification for configuration
RSIP : Restart in Progress Command. This command can be
initiated by either the MGC or gateway.
SPRT : Simple Packet Relay Transport
SSE : Silicon Switching Engine
TDM : Time Division Multiplexing
TGW : Target Gateway
TWC : Three Way Calling
VCCI : Virtual Circuit Connection Identifier
VMG : Virtual Media Gateway. It is a logical representation of
a module (or a set of modules) that has MG functionality.
There could be multiple VMGs in a device.
VoAAL2 : Voice over AAL2