Support for standards-compliant reference
interfaces — e2, e4 and Rq — enables
service providers to easily integrate the
Alcatel-Lucent 5750 SSC in a lar ger IMS
context, with the following functions:
• e2 reference interface — Interface
to external service control functions
(SCFs), allowing the query of
sub scriber and user-device state
infor ma tion maintained by the
Alcatel-Lucent 5750 SSC NASS
function.
• e4 reference interface — Used inter nally
between the Alcatel-Lucent 5750
SSC NASS and resource
and admission control sub system
(RACS); also enables inter facing with
external RACS functions.
• Rq reference interface — Allows
interworking with external policy
decision functions (PDFs) in the IMS
service-control layer. For example,
Rq can be used to inter face to a proxy
call session control function (P-
CSCF) to support band width
management for IMS-based services.
• ETSI TISPAN-compliant support of the
NASS and A-RACF — Support for
NGN/IMS service delivery on Alcatel-
Lucent’s TPSDA.
• ETSI TISPAN Rq, e2 and e4 interface
support — To integrate with an IMS
CSCF, PDF, SCF or external RACS.
Alcatel-Lucent 5750 Subscriber Services Controller 14
Figure 3. Alcatel-Lucent 5750 SSC Server and Database Redundancy
System Reliability and Scalability
The Alcatel-Lucent 5750 SSC soft -
ware can be deployed on a wide range
of single and multiprocessor server
platforms to optimize scalability,
and 1+1 or 1+n server/database
redundancy provides protection
against server or database failure
(see Figure 3). The Alcatel-Lucent
5750 SSC scales with service
providers’ needs as they add sub -
scribers and serv ices and expand the
network footprint.
