RFC 1221:Host Access Protocol (HAP) Specification ...
RFC-Ref

Internet Protocol


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... layer 3 lower, the protocol layer below the DoD Internet Protocol (IP) layer [3 ...


... bit in the Type of Service word was used to indicate the presence or absence of an Internet Protocol (IP) header (any version number ...
... destination host whether the data portion of the message contains an Internet Protocol (IP) header [3 ...
... host and the Service Agent were allowed to contain Internet Protocol headers. No hosts use that ...


... Postel, J., Editor, "Internet Protocol - DARPA Internet Program Protocol Specification ...



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