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. [Page 1] 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> ::= ::= [Page 2] 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 ] [Page 3]