Previous Table of Contents Next


AIN Architecture

The architecture of the AIN differs greatly from that of the traditional network, and even from that of IN/1. These differences largely deal with the nature and location of the programmed logic and the databases which drive the service offerings. The AIN architecture (Figure 11.13) includes SS7, Service Switching Points, Signal Transfer Points, Service Management Systems, Adjunct Processors, and Intelligent Peripherals.


Figure 11.13  Advanced Intelligent Network.(AIN) configuration supporting networked call centers

Common Channel Signaling System 7 (SS7)
as has been discussed, is an out-of-band signaling system for communication between devices in the carrier networks. SS7 is a requirement for ISDN and AIN. SS7 is being deployed throughout networks, worldwide and in support of all advanced networks and network services.
Service Switching Points (SSPs)
are PSTN switches that act on the instructions dictated by AIN centralized databases. SSPs can be end offices or tandem switches, as defined in the Chapter 6 discussion of the PSTN.
Signal Transfer Points (STPs)
are packet switches that route signaling and control messages between SSPs and SCPs, and between STPs.
Signal Control Points (SCPs)
contain all customer information in databases that reside on centralized network servers. SCPs provide routing and other instructions to SSPs, as requested and required.
Service Management Systems (SMSs)
are network control interfaces that allow the service provider to vary the parameters of the AIN services. Under certain circumstances, the user organization may be provided access to a partition of the SMS.
Adjunct Processors (APs)
are decentralized SCPs that support service offerings limited to a single SSP or a regional subset of SSPs. APs might support routing tables or authorization schemes specific to a single switch or regional subset of switches.
Intelligent Peripherals (IPs)
provide intelligent peripheral capabilities to enhance the delivery of certain services. For example, voice processing and voice recognition might be implemented in support of collect-call processing. Services such as AT&T’s 1-800-OPERATOR and MCI’s 1-800-COLLECT allow the processing of a collect or third-party billed call without operator intervention.
Voice recognition also can be used for voice printing, which allows for user authentication in highly secure applications. A number of LECs are providing automated directory assistance services, accomplishing database lookups based on voice recognition inputs through Intelligent Peripherals.

AIN Services

AIN services truly are open to the imagination. However, the availability of AINs is very uneven within the United States and, certainly, around the world. AIN services are of wide variety, including the following:

  Find-Me Service provides flexible and selective call forwarding. The numbers to which the calls are to be forwarded can be programmed and re-programmed from any location. Caller priority access can be subject to entry of proper passwords provided by the called party. Such capabilities recently have appeared in the commercial market, based on Intelligent Peripherals (IPs) known as Personal Assistants. Such systems also provide for scheduling of follow-up calls, provide scheduled reminder messages and maintain contact lists [11-54].
  Follow-Me Service provides for call forwarding on predetermined schedule. A telecommuter, for instance, might have the network forward calls to the home office three days a week during normal business hours. Calls would be directed to the traditional office two days a week. Calls clearly outside of normal business hours would automatically be directed to a voice mail system.
  Computer Security Service would automatically serve to provide secure access to networked hosts based on Caller ID, and supplemented by authorization codes. Additionally, the network would automatically keep a log of all access and access attempts, thereby providing an audit trail.
  Call Pickup Service, also known as Call Notification Service, provides for calls answered to be answered automatically by a voice processor. The called party can notified by pager, fax, e-mail, or other means. The priority of the calling party can be distinguished by the caller’s entering a privilege code provided by the called party. To pick up the call, the called party dials DISA port on the network switch and enters password codes in a manner to that used to accesses contemporary voice mail systems.
  Store Locator Service, also known as Single Number Dialing, provides the ability to advertise a single number. The network routes the call to closest store location, based on the originating address (telephone number) of the caller. This service is being deployed widely in the United States in support of pizza parlors and other restaurants offering delivery services. It also is used widely for directing calls to networked incoming call centers such as reservations centers (e.g., airlines, auto rental agencies and hotel chains).
  Multilocation Extension Dialing provides for network routing of calls based on abbreviated numbers. It is similar to a coordinated dialing plan in a networked PBX environment.
  Call Blocking typically supports the blocking of calls to international destinations, either in total or to specific country codes. Content Blocking supports the blocking of call to specific numbers, such as 900 numbers. This capability is deployed fairly commonly in many foreign networks, but is not widely available in the United States. Cellular radio providers have made extensive use of such capability in order to avoid cellular fraud involving certain countries in the Middle East, The Bahamas, and South and Central America. Ameritech offered Call Control Service on a trial basis (1994), allowing residential customers to block calls to specific numbers or to all numbers except those on an allowed list. Widespread deployment of such capabilities are unlikely in the near future; for instance, Ameritech estimated that only 46% of its residential access lines would have access to AIN by year-end 1996 [11-55]
  Caller Name is a variation of Caller ID, with linkage to directory services. The incoming call is identified on a Visual Display Unit (VDU) by originating number and associated directory listing. The VDU can either be built into the telephone or can be in the form of an adjunct unit that sits between the telephone and the circuit. In a CTI (Computer Telephony Integration) scenario, it can be in the form of a PC or computer workstation.
  Enhanced Call Return allows the subscriber to access what is, in effect, a highly sophisticated, network-based voice mail system. Bell Atlantic’s trial offering allows the user to call the system and enter security codes to gain access to the switch and data stores. A voice announcement will identify the date, time, and phone number of the last incoming call, at which point the return call can be launched by pressing a number on the telephone keypad [11-56].
  Enhanced Call Routing is a network-based enhancement to 800 calling. The callers are presented with options which allow them to specify their needs and then be connected with the offices or individuals best able to satisfy them. MCI and Stentor (Canada) began trials on such a system in early 1995, providing seamless interconnection between the United States and Canadian networks [11-57].
  Call Completion Service allows the Directory Assistance operator to extend the call automatically, perhaps at an additional charge. This capability is offered by cellular providers such as US West Cellular (at no additional charge) to avoid accidents caused by driving and dialing.
  Number Portability serves to provide portability of telephone numbers such as INWATS and 900 numbers. This function will be utilized increasingly as the regulators insist on portability of local numbers. Such portability is essential to facilitate local competition as decreed by the Telecommunications Act of 1996.


Previous Table of Contents Next