Feature Interactions

Two or more features of a telecommunications service are said to interact if one changes the functionality of the others. This problem, called the feature interaction problem, is a major obstacle to rapid creation of usable communications services.

Telecommunications service providers are eager to offer new services, but the development of these new services is hampered by interactions between the service features. Undetected and undesirable feature interactions cause confusion and dissatisfaction among the users of the features and add delay and expense to the development and deployment of new services and service features.

Feature interactions impact all phases of the software lifecycle. Timely mechanisms for resolving untoward feature interactions at all stages of the software lifecycle must be part of the new service development process. Otherwise, feature interactions will complicate system development and maintenance, causing delay in the introduction of new services to the market [bowe89].

Addressing Feature Interactions in the Requirements Stage

From 1995-1997, I led a group at Bellcore in developing Sculptor, which addresses the problem of feature interactions in the requirements stage of the lifecycle. Sculptor is a tool for designing and documenting the design of services. 

Formal methods can be used to detect feature interactions from requirements such as those produced by Sculptor. This year, I was in charge of a "Feature Interaction Detection Contest" for the 1998 Feature Interaction Workshop.  The instructions and features are attached in postscript files.   Also, a few feature definitions are available as gifs:

  •  POTS
  •  Call Forwarding Busy Line
  •  Calling Number Delivery
  • The winner of the contest was a group from Institut d'Informatique et de Mathématiques Appliquées de Grenoble, made up of Lydie du Bousquet and Nicolas Zuanon.

    Internet Telephony and an Architecture for Managing Feature Interactions

    A current project is to solve the feature interaction problem in new communications systems, such as Internet telephony and even multi-media systems. The approach to solving the problem in such systems will be quite different, because both the development environment and the deployment of features will follow a distributed paradigm. I am investigating the development of an architecture that will permit dynamically "pluggable" features.

    Previous Work on Feature Interactions


    In earlier work on feature interactions, I helped to develop a benchmark of prototypical feature
    interactions.

    I was also a member of the original design team for Bellcore's Touring Machine System, a platform for developing applications for broadband multimedia systems, and I was a co-inventor of negotiating agents, a mechanism for deciding what call to set up when end-users have policy conflicts.

    Publications

     
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    Last updated February 26, 1998.
    Copyright © 1997 Lucent Technologies. All rights reserved.