We have recently discussed NWG/RFCNos. 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
<ERR> <Code> <Command length> <Command in error>
<Code> is an eight-bit field that specifies the error type. The assigned codes are shown below. <Command length> is a 16-bit integer that indicates the length of the <Command in error> in bits. The <Command in error> is the spurious command.
The ranges of <Code> are shown below in hexidecimal.
Specific values of <Code> are shown below with their meaning.
<Code> value Semantics
00 Unspecified errors. 01 Request for an invalid resource. 02 Request for an exhausted resource, try later. 03-0F Unused. 10 Invalid <RSM>, i.e., link connected but unblocked. 11 Invalid <SPD>. 12 Invalid <ASG>, i.e., connected but no <RDY> received.
13 Message received on blocked link. 14-1F Unused. 20 Unknown command code. 21 Message received on unconnected link. 22 Invalid <RFC>. 23 Invalid <CLS>. 24 Invalid <RSM>, i.e., link not connected. 25 Invalid <FND>. 26 Invalid <END>. 27 Invalid <RDY>. 28 Invalid <ASG>, i.e., not connected. 29-2F Unused. 30-FF Unused.
QUERIES
<QRY> <My Socket> or <RPY> <Your Socket> <Text>
The <QRY> is the query indicated in NWG/RFC#39 and <RPY> is the reply. The format of <Text> is shown below; also refer to NWG/RFC#36, p. 3.
<Text>::= <16 bit count of relevant connection table entries> <relevant connection table entries>
<a relevant connection table entry>::= <local socket> <foreign socket> <link> <connection state> <flow state and buffer control> <reconnection control state>
<NOP>
An NCP may be up, down, pending, etc. When an NCP changes its state to UP it should send a <NOP> 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 <NOP> can update the availability of the sending NCP in its HOST status vector.
[ This RFCwas put into machine readable form for entry ] [ into the online RFCarchives by Richard Ames 6/97 ]
