RFC 46 (rfc46) - Page 2 of 17
ARPA Network protocol notes
Alternative Format: Original Text Document
RFC 46 ARPA Network Protocol Notes April 1970
does not preclude the existence of additional layers of protocol
between several installations so long as the basic protocol remains
supported.
We feel that three facilities must be provided for in the initial
protocol:
1. Multi-path communication between two existing processes which know
how to connect to each other.
2. A standard way for a process to connect to the logger (logging
process at a HOST) at a foreign HOST and request the creation of a
user process. (The login ritual may or may not be standardized.)
3. A standard way for a newly created process to initiate pseudo-
typewriter communication with the foreign process which requested
its creation.
The major differences between the protocol as proposed by Carr,
Crocker, and Cerf and this proposal are the following:
1. The dynamic reconnection strategy specified in Crocker's
NWG/RFC 36 is reserved for future implementation. We feel that
its inclusion would unduly complicate the initial implementation
of the protocol. We outline a strategy for foreign process
creation that does not require dynamic reconnection. Nothing in
this proposal precludes the implementation of dynamic reconnection
at a later date.
2. We propose that an "instance tag" be added to the socket
identifier so as to separate sockets belonging to different
processes of the same user coexisting at one HOST.
3. The following NCP commands have been added:
a. The ERR command specified in NWG/RFC 40 is included.
b. BLK and RSM commands are presented as possible alternatives to
the "cease on link" IMP command and SPD and RSM commands set
forth in NWG/RFC 36. Because these commands operate on socket
connections rather than link numbers, they do not impede the
implementation of socket connection multiplexing over a single
link number, should that later prove desirable.
c. An INT command that interrupts a process is specified. We feel
that it is highly important to be able to interrupt a process
that may be engaged in unwanted computation or output. To
implement the interrupt as a special format within a normal