diff options
author | Thomas Voss <mail@thomasvoss.com> | 2024-11-27 20:54:24 +0100 |
---|---|---|
committer | Thomas Voss <mail@thomasvoss.com> | 2024-11-27 20:54:24 +0100 |
commit | 4bfd864f10b68b71482b35c818559068ef8d5797 (patch) | |
tree | e3989f47a7994642eb325063d46e8f08ffa681dc /doc/rfc/rfc165.txt | |
parent | ea76e11061bda059ae9f9ad130a9895cc85607db (diff) |
doc: Add RFC documents
Diffstat (limited to 'doc/rfc/rfc165.txt')
-rw-r--r-- | doc/rfc/rfc165.txt | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/doc/rfc/rfc165.txt b/doc/rfc/rfc165.txt new file mode 100644 index 0000000..659c186 --- /dev/null +++ b/doc/rfc/rfc165.txt @@ -0,0 +1,283 @@ + + + + + + +Network Working Group J. Postel +Request for Comments: 165 UCLA - NMC +Obsoletes: 123, 143, 145 May 25, 1971 +NIC: 6779 + + + A Preferred Official Initial Connection Protocol* + + This document specifies the their level protocol used to connect a + user process at one site with a server process at another site. In + one instance, the user process will be a Telnet and the server + process will be a Logger, but there will be other cases. + + This document describes a family of Initial Connection Protocols + (ICP's) suitable for establishing one pair of connections between any + user process and any server process, and further to describe the + parameter values for connecting Telnets and Loggers. The description + will be at two levels, the third or user level, and the second or NCP + level. + +Third Level Description + +Notation + + There is no standard notation for describing system calls, which + initiate and close connections or cause data to be sent, so the + following *ad hoc* notation will be used. + + Init (local = l, foreign = f, size = s) + + Causes the local Host to attempt to establish a connection + between socket l at the local Host and socket f, with a byte + size of s for the connection. + + l is a 32 bit local socket number, + f is a 40 bit foreign socket number, the high-order eight + bits of which specify the foreign Host, and + s is an eight bit non-zero byte size. + + The sum of l and f must be odd. + + Listen (local = l, size = s) + + Causes the local Host to wait for a request for connection to + local socket l with byte size s. The process will be woken + when a connection is established. The parameters l and s are + the same as for Init. + + + + +Postel [Page 1] + +RFC 165 Initial Connection Protocol May 25, 1971 + + + Send (socket = l, data = d) + + The data named by d is sent over the connection attached to + local socket l. l must be a send socket attached to a + connection. d is the name of a data area. + + Receive (socket = l, data = d) + + The receive side counterpart to send. + + Close (socket = l) + + Any connection currently attached to local socket l is + closed. + +A Family of ICP's + + Briefly, a server process at a site attaches a well-advertised send + socket L and listens. A user process initiates connection to L from + its receive socket U. The byte size for this connection is 32. The + server process then transmits a 32-bit even number S and closes the + connection. The 32-bit number S and its successor, S+1, are the + socket numbers the server will use. The final steps are for sockets + S and S+1 at the server site to be connected to sockets U+3 and U+2 + respectively at the user site. + + Using the notation, the server executes the following sequence: + + Listen (socket = L, size = 32) + [Wait until a user connects] + Send (socket = L, data = S) + Close (socket = L) + Init (local = S, Foreign = U+3, size Bu) + Init (local = S+1, foreign = U+2, size Bs) + + The user executes the following: + + Init (local = U, foreign = L, size = 32) + Receive (socket = U, data = S) + Optional Close (socket = U) + Listen or Init (local U+3, foreign = S, size = Bu) + Listen or Init (local = U+2, foreign = S+1, size = Bs) + + Note that L is a send socket (odd), while S and U are receive sockets + (even). Where L, S, or U are used as values of local, they are 32- + bit numbers; where they are values of foreign, they are 40-bit + numbers. The parameters Bs and Bu are the byte sizes to be sent by + + + + +Postel [Page 2] + +RFC 165 Initial Connection Protocol May 25, 1971 + + + the server and user, respectively. If the user side declines to + close socket U, then it must be handled automatically by the second + level (see page 4). + + Examination of the above sequences reveals that an ICP is + characterized by three numbers L, Bs, and Bu, and must meet the + restrictions that + + a) L is a send socket, + b) Bs and Bu are legal byte sizes, and + c) For each L there is only one pair of associated byte sizes. + + This last restriction prevents two district services from being + available through the same socket and distinguished only by the byte + sizes. + +Second Level Description + +Notation + + The following notation will be used for the NCP Control Command used + in ICP. + + STR (_ls_, _fs_, _s_) + _ls_ = local send socket + _fs_ = foreign receive socket + _s_ = byte size + + RTS (_ls_, _fs_, _l_) + _ls_ = local receive socket + _fs_ = foreign send socket + _l_ = link + + ALL (_l_, _m_, _b_) + _l_ = link + _m_ = message allocation + _b_ = bit allocation + + CLS (_ls_, _fs_) + _ls_ = local socket + _fs_ = foreign socket + + + + + + + + + + +Postel [Page 3] + +RFC 165 Initial Connection Protocol May 25, 1971 + + + The same family of ICP's is now described again. + + Server User + + S1: listening on socket L. U1: RTS (U, L, _l1_) + + S2: Wait for match. U2: Wait for match. + + S3: STR (L, U, _s1_) + + S4: Wait for allocation. U3: All (_l1_, _m1_, _b1_) + + S5: Send data S in_s1_ bit U4: Receive data S in s1 bit bytes. + bytes as allowed by _s1_ bit bytes. + allocation m1_, _b1_). + + S6: CLS (L, U) U5: CLS (U, L) + + S7: RTS (S, U+3, _l2_) U6: STR (U+3, S, _s2_) + + S8: STR (S+1, U+2, _s3_) U7: RTS (U+2, S+1, _l3_) + + The labels here imply no ordering except that ordering required by + the Host-Host Protocol. Note that steps S7 and S8 can be reversed as + can U6 and U7. Also, notice that at any time after S2 the server + could initiate steps S7 and S8 in parallel with steps S3 through S6, + and that at any time after U4 the user could initiate steps U6 and U7 + in parallel with step U5. + + Following the above, exchanges ALL commands would be exchanged and + data transfers could begin. + + At this level the parameters of the above ICP family are L, _m1_, + _b1_, _s1_, _s2_, _s3_, _l1_, _l2_, _l3_. + + L is a well known socket number and will be specified for each type + of service. + + m1 and b1 are allocation quantities for the transfer of a socket + number. + + _m1_ is specified to be 1. + _b1_ is specified to be 32. + _s1_, _s2_, and _s3_ are byte sizes. Only _s1_ is to be specified + as _s2_ and _s3_ are to be left to the process involved. + _s1_ is specified to be 32. + + _l1_, _l2_, and _l3_ are links and are not specified. + + + +Postel [Page 4] + +RFC 165 Initial Connection Protocol May 25, 1971 + + + Note: Some hosts currently have difficulty sending 32 bit bytes. + Thus, it is temporarily allowed to send the socket number S as four 8 + bit bytes in one message. + + It is legal for the NCP to receive RTS or STR before the + corresponding local Init or Listen is issued. Therefore, it is + suggested that requests for connection to idle sockets be queued as + allowed by time and space limitations. + +Telnet - Logger ICP + + For connecting Telnet and Logger processes, the ICP parameters are + L=1, Bu, _s2_, and Bs = _s3_ = 8. (To clarify the socket number + required, L = X'00000001'). + +Formalities + + This proposed official protocol will become official if no serious + objections are raised before 2 June 71. A telephone survey of + Network Liaisons will be conducted by Jon Postel before that date. + If no objections are raised, this protocol will be declared official + by the Working Group chairman. + + * This document is based on RFC 123 by S. Crocker and discussions by + the ICP Committee. + + + + + + + + + + + + + + + + + + + + + + + + + + +Postel [Page 5] + |