IP Signaling Gateway (IPSG)
The IP Signaling Gateway (IPSG) feature provides a signaling gateway (SG) application as an alternative to the IPLIM and IPGW applications. However, the IPLIM and IPGW applications continue to be supported.
The IPSG feature can run the M2PA and M3UA protocols simultaneously on the same card. They can also have GTT-enabled capabilities support with SLIC running the 64-bit IPSG GPL. The feature also supports ANSI, ITU-N or ITUN-24, and ITU-I simultaneously on one card and one association.
The IPSG feature runs on the E5-ENET-B and SLIC cards with the IPSG application. An E5-ENET-B or SLIC card running the IPSG application is referred to as an IPSG card.
Note:
The following M3UA application server (AS) procedures are not currently supported by the IP Signaling Gateway (IPSG):- AS Pending procedure with non-zero T(recovery) timer
- AS Override traffic mode
The connection to the remote host is provided by IPSG M3UA and IPSG M2PA signaling links. An IPSG M3UA signaling link is a signaling link that is assigned to an IPSG linkset whose ADAPTER value is m3ua. An IPSG M2PA signaling link is a signaling link that is assigned to an IPSG linkset whose ADAPTER value is m2pa. A maximum of 128 IPSG M2PA or IPSG M3UA signaling links are supported per IPSG card running on SLIC hardware.
The IPSG M2PA signaling link can run the ANSI or ITU protocol, but not both simultaneously. ANSI and ITU can run on the same IPSG card on separate IPSG M2PA signaling links. ANSI and ITU can run on the same IPSG M3UA signaling link.
A series of three IS-NR link count thresholds are used to control the transition of the IPSG-M3UA links between Allowed, Restricted, and Prohibited states.
M2PA links on IPLIMx and IPSG cards can exist in the same linkset. M3UA links on IPSG and IPGWx cards cannot exist in the same linkset. M2PA and M3UA links cannot exist within the same linkset.
Each IPSG card running on SLIC hardware can host up to 128 SCTP associations. A maximum of 16 M3UA links or 1 M2PA link can be assigned to an association. M3UA and M2PA cannot be mixed on the same association.
The SCTP ADLER-32 or CRC-32 checksum algorithm can be selected for an individual IPLIM, IPGW, or IPSG card.
The adjacent point code (APC) of the IPSG-M3UA linkset is the point code assigned to an AS.
Provisioning for the IP Signaling Gateway feature uses the card, linkset, signaling link, IP card, IP link, IP host, and association database entities. The relationship between these entities is shown in Figure 2-18. The provisioning for the IP Signaling Gateway feature is shown in IPSG M2PA and M3UA Configuration Procedures.
Figure 2-18 IP Signaling Gateway Database Relationships
