Intelligent Networks: An architectural overview

In the last few years, the Internet has become the dominant driving force in the telecommunication Industry. Packet-based networks not only carry data but are beginning to carry voice and other traffic as well. Intelligent Network services are evolving quickly to meet these new demands.

Intelligent Network (IN), also known as Advanced Intelligent Network (AIN), is an evolving service-independent architecture introduced into the Public Switched Telephone Network (PSTN) over a decade ago in the US. The essence of IN architecture is to separate the service logic and intelligence from the switching environment and move them onto much more powerful and flexible general-purpose computers called Service Control Points (SCP). Such an architecture provides many advantages not only for the telecommunication service providers but also for their end-users. It allows service providers to create, deploy and maintain a wide variety of services quickly and economically by using a broad array of hardware, software and other development resources without the limitations of a proprietary switching environment. At the same time, it gives end-users the control over service definition and customization without requiring telecommunication service provider intervention.

Today, the number of new services supported by IN applications is rapidly growing. For example, a caller soon will be able to click on a product ad on a web page and automatically be connected to the product company’s closest local branch for ordering and delivery. Other services being implemented on pilot basis include, end-users controlling service features such as call-forwarding, call-waiting and call-screening directly from PCs at their homes or offices.

Here’s a glimpse of the architecture, which is going to support these overwhelming services.

Architectural Overview

Service Switching Point (SSP): The SSP is a telecommunication switch
that identifies and suspends calls requiring advanced service processing and
forwards them to an appropriate SCP via the Signaling Transfer Point (STP) or a
local adjunct to the SSP. The SCP/adjunct will interact with its database to
process the incoming service request and send a message back to the SSP. Upon
receipt of this message, the SSP will complete the call.

Service Control Point (SCP): The SCP is at the heart of the IN
services. It handles calls requiring advanced service processing. Normally, they
are deployed in mated pairs that duplicate the same capabilities to ensure high
availability and allow for load balancing. Each SCP may have several processors.
These processors may access a common database of services and subscribers or
each processor may have its own database, depending on the implementation. When
the SCP receives a request from an SSP, it may simply query its database for the
necessary information and then process the call. For instance, some customers
want calls to be routed to different physical locations, depending on the area
code of the caller. In this case the, SCP would simply look up which physical
location should receive the call and inform the SCP about the destination. In
other cases, the SCP may require further information from the user. To handle
these calls, the SCP will route the call to an Intelligent Peripheral (IP) that
can interface with the customer. For example, with credit card calls, the SCP
would route the call to an IP that could accept Touch-Tone input. Once the IP
had received the customer ’s credit card number, the SCP would verify its
validity and complete the call.

Adjunct: They perform the same function as the SCP, except that is it
used for one or a few services on a single switch. Typically this arrangement is
for supporting very fast response time, since the connection between an SSP and
an adjunct is local at high speed without the overhead of going through the STP.

Signaling Transfer Point (STP): They are intelligent routers that
route messages between SSPs and appropriate SCPs.

Intelligent Peripheral (IP): The intelligent peripheral is a device that can
connect to an IN call to provide services like tone generation, voice
recognition, playback, compression, call control, record and dual-tone
multi-frequency (DTMF) detection and collection. Examples of IPs are those that
process Touch-Tone and voice.

Service Management System (SMS): The SMS is responsible for
configuring SCPs, provisioning new services and updating SCP databases. The SMS
is also responsible for managing the operation of SCPs. It is used to manage the
master database that controls IN customer services. Each SMS can manage several
different SCPs offering different services. For example, an SMS may control one
SCP that handles a credit card service and another SCP that handles a virtual
private network service.

Service Creation Environment (SCE): The SCE is a non real-time system
for creating, testing and deploying new services. The SCE has a sophisticated
suite of tools for creating service processing logic. The SCE has a database
that contains common building blocks for services. By using these building
blocks, developers can create new services in a fraction of the time it would
take to create them from scratch. Since service providers can derive significant
leverage from an SCE that facilitates faster service development, the
implementation of SCE differs significantly from vendor to vendor.

In conclusion, the platform for rapid service deployment and customization
has been laid in the form Intelligent Networks. Now it is for the service
providers and the end users worldwide to exploit the potential of the
Intelligent Networks.