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- [ NETINFO:TP4-MEMO.TXT ] [ 8/86, FP ]
-
-
- The following memo from the DoD Interoperability and Standards office
- addresses the DoD plans for eventual transition to international
- standards, in particular, the ISO TP-4 protocol.
-
- ---------------------------------------------------------------------
-
-
- M E M O R A N D U M
-
- From: DoD Interoperability and Standards Office
-
- Date: 18 August 1986
-
- Subject: DoD Transition to ISO TP-4
-
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-
- DoD policy concerning a transition to ISO TP-4 was specified in a 3
- April 1985 Memorandum from Mr. Donald C. Latham, Assistant Secretary
- of Defense, Command, Control, Communications and Intelligence.
- "Whenever international standards are available and can be used to
- support military requirements, they will be implemented as rapidly as
- possible to obtain maximum economic and interoperability benefits.
- However, TP as a proven commercial offering is not available at this
- time. The progress of TP will be monitored carefully, and once
- commercially available, TP will be tested and evaluated for use in
- military applications." Further study by DoD has indicated that a one
- layer transition from TCP to TP-4 is not viable. Any transition
- should happen on an "all layers" basis to preclude multiple
- transitions and modifications of layer interfaces. Full seven-layer
- implementations of ISO protocols are only just now being announced.
- (Note that DoD is already essentially ISO conformant/compatible at
- layer 3 and below.)
-
- The ISO protocols can be characterized as having many optional
- features. In the DoD environment, to ensure maximum interoperability
- and often to meet specific military requirements, the options must be
- more narrowly specified. DoD Military Specification Supplements for
- each of the ISO protocols are under development. Tests for
- conformance to these MIL-Spec-Supplements are also planned. It must
- be emphasized that the objective is not to create DoD unique versions
- of commercial protocol products, but to define an options set.
- Possible modification of an ISO protocol is not ruled out, however, if
- it is determined that the ISO protocol does not satisfy specific
- military requirements.
-
- The National Research Council report "Transport Protocols for
- Department of Defense Data Networks," (RFC:RFC942.TXT) recommended
- that a method for ISO protocols to interoperate with current DoD
- protocols should be developed. This is underway with the development
- of an "Application Layer Translating Gateway" for both file transfer
- and mail service for the two protocol suites. When this work is
- complete and the Supplement specifications and tests are available,
- DoD expects to announce Co-Standard status for the ISO protocols.
- This is expected within 18 months. A date that new networks will be
- required to use ISO protocols has not yet been determined. In the
- case of existing DoD networks with no need to interoperate with
- others, the current DoD protocols may not be phased out through the
- lifetime of that network.
-