Store, Carry and Forward Testing Requirements

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 . Detailed terminology is given in the SCF Requirements and Expectations document and will not be repeated here.

This document provides guidelines and requirements for testing Store, Carry and Forward (SCF) systems and protocols. The Testing Requirements document is one of three that fully describe the SCF system. The other two are the SCF Problem Statement and the SCF Requirements and Expectations document. As background, the SCF Problem Statement and SCF Requirements and Expectations documents are suggested reading. The SCF Problem Statement describes the core SCF problem and gives an assessment of the ability to use existing technologies as solutions. In addition, it provides a number of SCF deployment scenarios. In RFC760, one can fine what has become know as Postel's Law or the Robustness Principal, "In general, an implementation should be conservative in its sending behavior, and liberal in its receiving behavior." This rule was originally targeting protocol implementation. A corresponding rule for testing may be, "If you claim the protocol can do it, you have to prove it - test it." Conversely, being able to PING an end system does not indicate the network is fully functional. It just means there is connectivity and a potential that the network is fully functional. The primary motivation for developing this document is to establish thorough, repeatable tests that will fully exercise a SCF system. Past experience has shown that testing of SCF systems to often be inadequate. For example, tests have been performed on SCF systems in fully connected, high bandwidth networks where only forwarding would be exercised or the traffic would be so minimal as to never tax the storage or queueing. Such tests are valid as a starting point, but insufficient to determine that a protocol or implementation will working properly in a reasonably scaled deployment. A secondary motivation is to improve implementations by providing a known test environment. Knowing some possible ways that the protocol and system will be evaluated may help establish how the code is developed as well as identifying hooks for monitoring particular processes.

Figure 1 illustrates a generic testbed for testing may aspects of the SCF protocol. The systems consists of 12 SCF agents and 16 links. Any or all of the links may be disconnected at any given time. Even though the system is simple, it is still rather complex but the complexity is necessary because the system must accommodate testing of aggregation, deaggregation, and fragmentation with multiple container flows of various sizes and priorities.

SCF Test Network/postamble

List requirements and test for each of the protocol requirements in the "SCF Requirements and Expectations" document .

This document is informative and provides guidelines and Requirements for testing SCF systems and protocols. There are no security considerations.

This document neither creates nor updates any registries or codepoints, so there are no IANA Considerations.

Work on this document at NASA's Glenn Research Center was funded by the NASA Glenn Research Center Innovation Funds. Many thanks to Denise Ponchak for aiding in obtaining financial supporting for this activity.