Network Working Group E. Harslem
Request for Comments: 40 J. Heafner
RAND
March 1970
More Comments on the Forthcoming Protocol
We have recently discussed NWG/RFC Nos. 36 and 39 with Steve Crocker,
UCLA. Steve has asked that we elaborate on the errors, queries, and
HOST status that were mentioned in NWG/RFC #39.
Please voice your opinions soon in order to affect the forthcoming
protocol specifications.
ERROR MESSAGES
is an eight-bit field that specifies the error type. The
assigned codes are shown below. is a 16-bit integer
that indicates the length of the in bits. The
is the spurious command.
The ranges of are shown below in hexidecimal.
00 Unspecified error types
10-0F Resource errors
10-1F Status errors
20-2F Content errors
30-3F Unused
Specific values of are shown below with their meaning.
value Semantics
00 Unspecified errors.
01 Request for an invalid resource.
02 Request for an exhausted resource, try later.
03-0F Unused.
10 Invalid , i.e., link connected but unblocked.
11 Invalid .
12 Invalid , i.e., connected but no
received.
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value Semantics
13 Message received on blocked link.
14-1F Unused.
20 Unknown command code.
21 Message received on unconnected link.
22 Invalid .
23 Invalid .
24 Invalid , i.e., link not connected.
25 Invalid .
26 Invalid .
27 Invalid .
28 Invalid , i.e., not connected.
29-2F Unused.
30-FF Unused.
QUERIES
or
The is the query indicated in NWG/RFC #39 and is the reply.
The format of is shown below; also refer to NWG/RFC #36, p. 3.
::= <16 bit count of relevant connection table entries>
::=
::=
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HOST STATUS
An NCP may be up, down, pending, etc. When an NCP changes its
state to UP it should send a to each remote NCP which
indicates the NCP is available. The sending NCP can then
construct a vector of HOST status from the RFNMs it receives. An
NCP receiving a can update the availability of the sending
NCP in its HOST status vector.
[ This RFC was put into machine readable form for entry ]
[ into the online RFC archives by Richard Ames 6/97 ]
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RFC, FYI, BCP