Implementing Remote procedure calls

Andrew D. Birrell, Bruce Jay Nelson
1983 ACM SIGOPS Operating Systems Review  
Remote procedure calls (RPC) appear to be a useful paradig m for providing communication across a network between programs written in a high-level language. This paper describes a package providing a remote procedure call facility, the options that face the designer of such a package, and the decisions ~we made. We describe the overall structure of our RPC mechanism, our facilities for binding RPC clients, the transport level communication protocol, and some performance measurements. We include
more » ... rements. We include descriptioro~ of some optimizations used to achieve high performance and to minimize the load on server machines that have many clients. still execute (depending on the details of the parallelism of that environment and the RPC implementation). There are many attractive aspects to this idea. One is clean and simple semantics: these should make it easier to build distributed computations, and to get them right. Another is efficiency: procedure calls seem simple enough for the communication to be quite rapid. A third is generality: in singie-machine computations, procedures are often the most important mechanism for communication between parts of the algorithm. The idea of RPC has been around for many years. It has been discussed in the public literature many times since at least as far back as 1976 [15] . Nelson's doctoral dissertation [13] is an extensive examination of the design possibilities for an RPC system and has references to much of the previous work on RPC. However, full-scale implementations of RPC have been rarer than paper designs. Notable recent efforts include Courier in the Xerox NS family of protocols [4], and current work at MIT [10]. This paper results from the construction of an RPC facility for the Cedar project. We felt, because of earlier work (particularly Nelson's thesis and associated experiments), that we understood the choices the designer of an RPC facility must make. Our task was to make the choices in light of our particular aims and environment. In practice, we found that several areas were inadequately understood, and we produced a system whose design has several novel aspects. Major issues facing the designer of an RPC facility include: the precise semantics of a call in the presence of machine and communication failures; the semantics of address-containing arguments in the (possible) absence of a shared address space; integration of remote calls into existing (or future) programming systems; binding (how a caller determines the location and identity of the callee); suitable protocols for transfer of data and control between caller and callee; and how to provide data integrity and security (if desired) in an open communication network. In building our RPC package we addressed each of these issues, but it not possible to describe all of them in suitable depth in a single paper. This paper includes a discussion of the issues and our major decisions about them, and describes the overall structure of our solution. We also describe in some detail our binding mechanism and our transport level communication protocol. We plan to produce subsequent papers describing our facilities for encryption-based security, and providing more information about the manufacture of the stub modules (which are responsible for the interpretation of arguments and results of RPC calls) and our experiences with practical use of this facility.
doi:10.1145/773379.806609 fatcat:tajvvi7vgjhgdihlg6haprbega