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No abstract

The paper, by one of its developers, describes the conceptual framework in which the ARPANET intercomputer networking protocol suite, including the DoD standard Transmission Control Protocol (TCP) and Internet Protocol (IP), were designed. It also compares and contrasts several aspects of the ARPANET Reference Model (ARM) with the more widely publicized International Standards Organization's Reference Model for Open System Interconnection (ISORM).

The sometimes-held position that the DoD Standard Transmission Control Protocol (TCP) and Internet Protocol (IP) are inappropriate for use "on" a Local Area Network (LAN) is shown to be fallacious. The paper is a companion piece to M82-47, M82-49, M82-50, and M82-51. i

The growth of autonomous intercomputer networks has led to a desire on the part of their respective proprietors to "gateway" from one to the other. Unfortunately, however, the implications and shortcomings of gateways which must translate or map between differing protocol suites are not widely understood. Some protocol sets have such severe functionality mismatches that proper T/MG's cannot be generated for them; all attempts to mesh heterogeneous suites are subject to numerous problems, including the introduction of "singularity points" on logical connections which would otherwise be able to enjoy the advantages of communications subnetwork alternate routing, loss of functionality, difficulty of Flow Control resolution, higher cost than non-translating/mapping Gateways, and the necessity of re-creating T/MG's when a given suite changes. The preferability of a protocol-compatible internet is also touched upon, as is the psychology of those soi-disant architects who posit T/MG's.i