Quality Assurance and Differentiation of Internet Services
Internet services have a characteristic of bursty traffic.
To deal with the burstiness and protect valuable
customers from traffic surge, a stress-resilient server must be able
to control the quality of different classes
of requests in a coordinated way so as to guarantee a fair and graceful
performance degradation in stress conditions.
Such quality assurance and differentiation technologies can also protect
the server from distributed denial-of-service
attacks by downgrading the service quality of the requests with suspicious
intentions. The goal of QUADIS project
is to develop an application-level multi-resource management mechanism
and coordinated admission/resource allocaiton and space/time request
scheduling strategies for stress-resilience and high
service availability in web servers .
Research has been carried out in the following aspects:
- Proposed two feedback control approaches: model predictive feedback
control and model-free self-tuning fuzzy control, to provide service
quality diferentiation and assurance in Internet servers. Early studies focused
on service quality in terms of primary metrics like request queueing delay
and processing time in web servers, e-commerce servers, and streaming servers;
Recent research advanced the technoogies to QoS control in terms of
client-perceived end-to-end pageview response time with respect to dynamic
multi-objects web pages; see[5,6].
- Proposed an online non-intrusive measurement approach to estimate
client-perceived pageview response time. Previous studies were limited to
measurement of HTTP-based web services. Our sMonitor approach advanced
the technology to the measurement of HTTPS-based secure web services .
- C. Xu, Scalable and Secure Internet Services and Architecture, Chapman &
Hall/CRC, June 2005, ISBN 1-5848-8377-4 (pp395+xvii)
- X. Zhou and C. Xu, "Harmonic bandwidth allocation for service differentiation
on streaming servers,” IEEE Transaction on Parallel and Distributed
Computing, Vol.15 (9):835-848, Sept. 2004.
- J. Wei, X. Zhou and C. Xu, “Robust processing rate allocation for proportional
slowdown differentiation on Internet servers,” IEEE Transactions on
Computers, Vol.54 (8):964-977, August 2005.
- X. Zhou, J. Wei, and C. Xu, "Resource allocation for session-based 2D service
differentiation on e-commerce servers,” IEEE Transactions on Parallel and
Distributed Systems, Vol.17 (8):838-850, August 2006.
- C. Xu, J. Wei and B. Liu, “Model predictive feedback control for end-to-end
QoS guarantees in Web servers”, IEEE Computers (to appear)
- J. Wei and C. Xu, “eQoS: Provisioning of client-perceived end-to-end QoS
guarantees in Web servers,” IEEE Transactions on Computers. Vol.
55(12):1543-1556, December 2006.
- J. Wei and C. Xu, “sMonitor: A non-intrusive client-perceived end-to-end
performance monitor of secured Internet services,” in Proc. of USENIX Annual
Technical Conf. Boston, June 2006.