Script-driven packet marking for quality-of-service support in legacy applications
Timothy Roscoe, Gene Bowen · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1999
This paper describes the implementation of a system to deliver Quality of Service for IP flows using a DiffServ- like packet marking mechanism. The system uses an unmodified commodity operating system (Windows NT), and a policy daemon is employed to implement arbitrary policies for QoS via a scripting mechanism. By interposing an agent in the protocol stack used by the application runtime system, off-the-shelf applications can have different packet forwarding policies assigned to different flows they originate, without any need to recompile either the operating system or the application. The principle of the system can be naturally extended to implement more widely coordinated policy-based networking, and network reservations using protocols such as RSVP, without any need to recompile applications.