Anypoint: a network communication model for internet services
Kenneth Yocum, Jeffrey S. Chase · 2003
Anypoint is a new network communication model for building Internet services from clusters or ensemble sites, aggregations of end nodes that provide scalable, high-performance, fault-tolerant services. Anypoint provides a robust transport-layer of the service. Extensible Anypoint switches support pluggable indirection policies that mediate communication between client and ensemble. The model allows the virtualization of existing and emerging request/response service protocols that leverage reliable, ordered, rate controlled transport protocols. This dissertation proposes the transport switching indirection architecture, an aggressive realization of the Anypoint communication model. While current indirection proposals are fragile and ad-hoc, transport switching is efficient, extensible, and flexible. It is the first architecture to switch at the granularity of transport frames, and is designed for emerging transports with application-level framing. It supports the creation of appliance-oriented services through pluggable switch routing modules that can inspect, transform, and redirect individual requests/responses in transport-layer flows. This work studies indirection in a comprehensive fashion. (1) It identifies the Anypoint communication model and codifies the roll of indirecting network intermediaries to inter-operate with existing Internet infrastructure. Transport switches do not terminate transport connections, restoring end-to-end transport reliability. (2) It identifies the endpoint transport functions required to support transport switching. These features allow service protocols to take advantage of the Anypoint model and transport switching. (3) It defines the rate control behavior of Anypoint connections, and leverages existing explicit rate control techniques (XCP) to develop a unified rate control solution for managing network bandwidth and endpoint buffering. (4) It explores Anypoint-compatible services through the construction of an NFS-compatible storage switch. Slite unifies stock NFSv3 servers behind a transport switch to provide a scalable storage appliance. (5) It evaluates a prototype transport switch, advanced message-based transport protocol, and the Slite storage appliance. It compares transport switching to an alternative application-layer indirection architecture, and develops a scalable and accurate network emulation environment to test Anypoint rate control concepts. This work explores the use of indirection in the Internet and advances service design, and transport and service protocols for ensemble-based Internet services.