Technion - Israel Institute of Technology
Computer Networks Lab. - EE Department

Connectionless Datagram Traffic in ATM Network

Research Thesis

Elazar Raab (eraab@tx.technion.ac.il)
Supervisor: Prof. Raphael Rom
June 2000
ATM is a connection-oriented network technology offering the best mechanism yet  for high-speed Quality-of-Service (QoS) provision, a well needed ability for modern real-time applications and content delivery. Over a decade after its emergence it is well spread as a backbone infrastructure in many networks but somehow has failed to reach the desktop. One of the reasons is that although ATM is the perfect answer for the QoS needs, most desktop applications today still rely on classic connectionless networking protocols like IP.

Many solutions have been offered to confront the discrepancy between the connection-oriented nature of ATM and the bursty connectionless nature of classic applications. In this thesis existing solutions to the problem are discussed and their drawbacks are pointed out.

Based on analysis of the existing solutions, this work presentes a new approach to the problem, the CL-ATM approach. CL-ATM integrates connectionless traffic support into ATM switches while keeping the standard ATM signalling in tact. This approach allows efficient delivery of connectionless traffic while retaining the QoS capabilities of ATM. CL-ATM eliminate the need for a dedicated virtual channel (VC) in order to forward connectionless traffic. In addition, it exploits the VC mechanism and its QoS provision property in order to forward the connection less traffic efficiently while providing a ''Better-than-Best-Effort`` quality of service.

In addition to a definition of the architecture of the CL-ATM service, this research provides an implementation of the CL-ATM suite as an ATM switch control module in Solaris 7 OS kernel. This system was used to conduct experiments over the CL-ATM service.

Thesis book in gzipped Postscript format (~1.3MB)

Thesis book in gzipped PDF format (~1.2MB)

CL-ATM system project tree (source files, etc.) (~930KB)