Remembering the Future

The suckline is the decision to use the lowest common denominator capabilities across participating nodes in order to [achieve] guaranteed communications." The suckline, by this definition, is the lowest level of shared context that still permits interaction.

But of course in an ideal world, no one wants to operate at the suckline — hence its name. So Jeff posits the notion that, "Web services are about protocol negotiation." The suckline becomes merely an opening gambit, an entry point that allows participants to discover their common ground and then step up to a deeper, more tightly coupled level of interaction: "If the protocol negotiation is done correctly you should be able to use a metadata-described invocation and interface description mechanism that is linked to a protocol policy for runtime resolution," which then allows the participants to step up to a "Greatest Common Factor (GCF)" level of interaction.