An Implementation Method of IN Functional Entities on Top of Distributed Operating System and Its Performance Evaluation Using Experimental System

Masahiko FUJINAGA  Toshihiko KATO  Kenji SUZUKI  

Publication
IEICE TRANSACTIONS on Communications   Vol.E75-B   No.10   pp.1043-1051
Publication Date: 1992/10/25
Online ISSN: 
DOI: 
Print ISSN: 0916-8516
Type of Manuscript: Special Section PAPER (Special Issue on Communication Software Technologies)
Category: 
Keyword: 
intelligent network,  distributed operating system,  remote procedure call,  lightweight process,  

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Summary: 
In order to make the implementation of network components flexible and cost effective, it is required to use widely available technologies as the implementation platform. The distributed operating systems can be adopted as such a platform, because they allow to implement a network component using multiple computers connected through a local area network. In this paper, we focus on the Intelligent Network (IN) whose network components are modelled as Functional Entities (FEs), and describe an implementation method of FEs using distributed operating systems. Our method is summarized as follows:
・ The remote procedure call (RPC) is used for the access transparent inter-process communication.
・ The lightweight process mechanism is used for handling concurrent requests.
・ CCF/SSF (Call Control Function/Service Control Function) and SDF (Service Data Function) are implemented as an SSF server and an SDF server, respectively.
・ SCF (Service Control Function) is composed of a Service Dispatcher and a set of Service Executors.
・ The Service Dispatcher accepts all the requests for IN call processing and dispatches them to appropriate Service Executors.
・ Service Executors are created for the individual IN services and execute the service logics.
・ SDF server and Service Executor may be replicated for load partitioning.
This paper has also described the implementation of experimental system supporting "Freephone" service based on our method, and showed the performance evaluation of the experimental system in terms of the real-time and concurrent call processing of IN services. We used Mach and SUN OS as a platform for implementing the servers for FEs. The experimental system using four workstations shows that it can handle up to 170IN calls in one second with the additional response time of less than 200msec, which is small enough compared with the response time for the basic connection control. Those results prove that our method is feasible for implementing practical FEs.