FöRFATTARE
Torger, Anders; Lidén, Erik

DATUM
2000-04-28

INSTITUTION
Systemteknik / Datorkommunikation

SAMMANFATTNING
In the last years of Internet's existence, a market for quality services in the sense of bandwidth reservations has started to evolve. When building systems that support these kind of services, it is desirable to have a standardised protocol to configure nodes in the network to meet ordered policies. COPS, Common Open Policy Service, is the name of a new extensible base protocol designed for this purpose. The extension COPS-PR, COPS usage for Policy Provisioning, is used for provisioning policies on the nodes of a network.

The purpose of our work presented in this thesis is to implement COPS and COPS-PR, and then evaluate the protocols by theoretical analysis and practical tests on our implementations. In the theoretical part, there will be a comparison with the major competitor in this area, namely SNMP, the Simple Network Management Protocol. It has existed for several years and is a well established protocol for general network management.

We implement COPS and COPS-PR as high-level C-libraries for Unix platforms. Implementation in C together with a carefully crafted architecture grants for high performance and good scalability. To test the implementations, simple test programs using the libraries are made and run in a controlled lab environment. In the theoretical evaluation, gathered facts and opinions mainly from the ongoing COPS versus SNMP debate are carefully analysed. The transport protocol issue is given extra attention.

The measurements performed on our implementation of the base COPS protocol show good performance and scalability. A low-end machine is shown to handle 800 COPS clients in a controlled way. Our COPS-PR implementation is compared with a common SNMP implementation, where the former is shown to have the better performance. In the theoretical comparison between COPS-based and SNMP-based systems for policy provisioning, it is strongly suggested that COPS is technically superior, although SNMP might have economical advantages due to its well established user base.

In conclusion, COPS and its extension COPS-PR are indeed feasible protocols for use in policy provisioning systems. It is also technically superior to the main alternative, which is SNMP. However, the question if the technical superiority can motivate eventual increased cost in deployment of this new technology remains unanswered.

ISSN 1402-1617 / ISRN LTU-EX--00/125--SE / NR 2000:125