On replica placement for QoS-aware content distribution

The rapid growth of time-critical information services and business-oriented applications is making quality of service (QoS) support increasingly important in content distribution. This paper investigates the problem of placing object replicas (e.g., web pages and images) to meet the QoS requirements of clients with the objective of minimizing the replication cost. We consider two classes of service models: replica-aware service and replica-blind service. In the replica-aware model, the servers are aware of the locations of replicas and can therefore direct requests to the nearest replica. We show that the QoS-aware placement problem for replica-aware services is NP-complete. Several heuristic algorithms for efficient computation of suboptimal solutions are proposed and experimentally evaluated. In the replica-blind model, the servers are not aware of the locations of replicas or even their existence. As a result, each replica only serves the requests flowing through it under some given routing strategy. We show that there exist polynomial optimal solutions to the QoS-aware placement problem for replica-blind services. Efficient algorithms are proposed to compute the optimal locations of replicas under different cost models.

[1]  Konstantinos Kalpakis,et al.  Optimal Placement of Replicas in Trees with Read, Write, and Storage Costs , 2001, IEEE Trans. Parallel Distributed Syst..

[2]  Lawrence W. Dowdy,et al.  Comparative Models of the File Assignment Problem , 1982, CSUR.

[3]  Hui Zhang,et al.  A case for end system multicast (keynote address) , 2000, SIGMETRICS '00.

[4]  Dorit S. Hochbaum,et al.  Database Location in Computer Networks , 1980, JACM.

[5]  Syam Gadde,et al.  Not all Hits are Created Equal: Cooperative Proxy Caching Over a Wide-Area Network , 1998, Comput. Networks.

[6]  Xueyan Tang,et al.  Coordinated management of cascaded caches for efficient content distribution , 2003, Proceedings 19th International Conference on Data Engineering (Cat. No.03CH37405).

[7]  Lixia Zhang,et al.  Host multicast: a framework for delivering multicast to end users , 2002, Proceedings.Twenty-First Annual Joint Conference of the IEEE Computer and Communications Societies.

[8]  Lili Qiu,et al.  On the placement of Web server replicas , 2001, Proceedings IEEE INFOCOM 2001. Conference on Computer Communications. Twentieth Annual Joint Conference of the IEEE Computer and Communications Society (Cat. No.01CH37213).

[9]  David S. Johnson,et al.  Computers and Intractability: A Guide to the Theory of NP-Completeness , 1978 .

[10]  Yuval Shavitt,et al.  Constrained mirror placement on the Internet , 2002, IEEE J. Sel. Areas Commun..

[11]  Shay Kutten,et al.  Optimal allocation of electronic content , 2001, Proceedings IEEE INFOCOM 2001. Conference on Computer Communications. Twentieth Annual Joint Conference of the IEEE Computer and Communications Society (Cat. No.01CH37213).

[12]  Daniel A. Menascé,et al.  QoS Issues in Web Services , 2002, IEEE Internet Comput..

[13]  P. Krishnan,et al.  The cache location problem , 2000, TNET.

[14]  Pablo Rodriguez,et al.  Analysis of web caching architectures: hierarchical and distributed caching , 2001, TNET.

[15]  Peter B. Danzig,et al.  A Hierarchical Internet Object Cache , 1996, USENIX ATC.

[16]  Srinivasan Seshan,et al.  A case for end system multicast , 2002, IEEE J. Sel. Areas Commun..

[17]  Deying Li,et al.  Placement of Web-Server Proxies with Consideration of Read and Update Operations on the Internet , 2003, Comput. J..

[18]  Yuval Shavitt,et al.  Constrained mirror placement on the Internet , 2001, Proceedings IEEE INFOCOM 2001. Conference on Computer Communications. Twentieth Annual Joint Conference of the IEEE Computer and Communications Society (Cat. No.01CH37213).

[19]  Pablo Rodriguez,et al.  SPREAD: Scalable platform for reliable and efficient automated distribution , 2000, Comput. Networks.

[20]  Michael Dahlin,et al.  Coordinated Placement and Replacement for Large-Scale Distributed Caches , 2002, IEEE Trans. Knowl. Data Eng..

[21]  Jianliang Xu,et al.  Placement problems for transparent data replication proxy services , 2002, IEEE J. Sel. Areas Commun..

[22]  Bo Li,et al.  On the optimal placement of web proxies in the Internet , 1999, IEEE INFOCOM '99. Conference on Computer Communications. Proceedings. Eighteenth Annual Joint Conference of the IEEE Computer and Communications Societies. The Future is Now (Cat. No.99CH36320).

[23]  Ouri Wolfson,et al.  The multicast policy and its relationship to replicated data placement , 1991, TODS.

[24]  BERNARD M. WAXMAN,et al.  Routing of multipoint connections , 1988, IEEE J. Sel. Areas Commun..

[25]  Xueyan Tang,et al.  Coordinated En-Route Web Caching , 2002, IEEE Trans. Computers.