Security is a central concern in Communication Networks. Secure communication requires a robust underlying network architecture. A key characteristic of robust networks is their ability to isolate, when required, one flow (or aggregate of flows) from another, so as to provide guaranteed QoS (quality of service) to specific flows in the presence of other, misbehaving flows that share the same network links and resources. This requires "multi-lane" architectures, which eliminate head-of-line blocking.
Network Vulnerabilities due to shared-queue (HOL blocking) architectures include:
For robust and scalable multi-lane networks, the following research topics must be addressed:
Per-Flow Queueing (1996-2001) - Managing Thousands of Queues at High Speed: Per-flow queueing typically requires the implementation of a large number of logical queues --hundreds or thousands to possibly millions in the future-- inside one or a few physical memories. When the communication system is to operate at high speed, the management of these multiple queues typically requires the assistance of specialized hardware. We have worked on such multi-queue management implementations at different cost and performance levels.
Weighted-Round-Robin (WRR) Scheduling (1985-2002): Our work started in 1985 with an investigation of several techniques for performing round-robin scheduling at high speed among a large number of flows. Later, in 1990, we designed a WRR scheduler for hundreds of flows, using a CAM in CMOS VLSI. More recently, since 1996, we developed techniques for WRR scheduling and Weighted Fair Queueing (WFQ) among many thousands of flows at a relatively low cost, or at very high speed.
Multiple Priority Levels in Buffered Crossbars (2003-04):
We proposed the effective use of two-lane limited resources
within a buffered crossbar switch,
by adaptively mapping onto them
the multiple priority levels supported by the line cards.
This two-level flow-aggregation scheme
performs almost identically to a multi-lane system,
by exploiting the relatively short round-trip time (RTT)
between its levels of hierarchy (line cards, crossbar switch)
and the consequent small size of the crossbar buffers.
Information Security R&D
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last updated: Sep. 2004, by M. Katevenis.