📄 rfc1085.txt
字号:
Event: user-initiated Abort PDU received The provider issues the P-U-ABORT.INDICATION primitive and enters the IDLE state. Event: any other PDU received If the PDU is not an Abort PDU, the provider constructs a provider- initiated Abort PDU, which is put on the input queue for the serializer. Regardless, The provider issues the P-P-ABORT.INDICATION primitive and enters the the IDLE state. DATA state Event: P-DATA.REQUEST primitive issued The user data parameter is placed in a UserData PDU, which is put on the input queue for the serializer. The provider remains in the DATA state. Event: P-RELEASE.REQUEST primitive issued The user data parameter is placed in a ReleaseRequest PDU, which is put on the input queue for the serializer. For the udp-based service, the provider sets the retransmission counter to a small value (e.g., 2), and now starts a small timer. Regardless, the provider enters the WAIT3 state. Event: P-U-ABORT.REQUEST primitive issued The user data parameter is placed in an Abort PDU, which is put on the input queue for the serializer. The provider enters the IDLE state.Rose [Page 20]RFC 1085 ISO Presentation Services December 1988 Event: UserData PDU received The provider issues the P-DATA.INDICATION primitive and remains in the DATA state. Event: ReleaseRequest PDU received The provider issues the P-RELEASE.INDICATION primitive, and enters the WAIT4 state. Event: user-initiated Abort PDU received The provider issues the P-U-ABORT.INDICATION primitive and enters the IDLE state. Event: any other PDU received If the PDU is not an Abort PDU, the provider constructs a provider- initiated Abort PDU, which is put on the input queue for the serializer. Regardless, the provider issues the P-P-ABORT.INDICATION primitive and enters the the IDLE state. WAIT3 state Event: P-U-ABORT.REQUEST primitive issued The user data parameter is placed in an Abort PDU, which is put on the input queue for the serializer. The provider enters the IDLE state. Event: ReleaseResponse PDU received For the udp-based service, the timer is cancelled. The provider issues the P-RELEASE.CONFIRMATION primitive and enters the IDLE state. Event: user-initiated Abort PDU received The provider issues the P-U-ABORT.INDICATION primitive and enters the IDLE state.Rose [Page 21]RFC 1085 ISO Presentation Services December 1988 Event: any other PDU received If the PDU is not an Abort PDU, the provider constructs a provider- initiated Abort PDU, which is put on the input queue for the serializer. Regardless, the provider issues the P-P-ABORT.INDICATION primitive and enters the the IDLE state. Event: timer expires The provider decrements the retransmission counter. If the resulting value is less than or equal to zero, the provider constructs a provider-initiated Abort PDU, which is put on the input queue for the serializer. It then issues the P-P-ABORT.INDICATION primitive and enters the IDLE state. Otherwise, a ReleaseRequest PDU is put on the input queue for the serializer, the small timer is started again, and the provider remains in the WAIT3 state. WAIT4 state Event: P-RELEASE.RESPONSE primitive issued The user data parameter is placed in a ReleaseResponse PDU, which is put on the input queue for the serializer. The provider now enters the IDLE state. Event: P-U-ABORT.REQUEST primitive issued The user data parameter is placed in an Abort PDU, which is put on the input queue for the serializer. The provider now enters the IDLE state. Event: user-initiated Abort PDU received The provider issues the P-U-ABORT.INDICATION primitive and enters the IDLE state. Event: any other PDU received If the PDU is not an Abort PDU, the provider constructs a provider- initiated Abort PDU, which is put on the input queue for the serializer. Regardless, the provider issues the P-P-ABORT.INDICATION primitive and enters the the IDLE state.Rose [Page 22]RFC 1085 ISO Presentation Services December 198811. Directory Services Although not properly part of the presentation service, this memo assumes and specifies a minimal Directory service capability for use by the application-entity. The function of the Directory Service Element is to provide two mappings: first, a service name is mapped into an application entity title, which is a global handle on the service; and, second, the application-entity title is mapped onto a presentation address. The structure of presentation addresses were defined in Section 5. The structure of application-entity titles is less solidly agreed upon at the present time. Since objects of this type are not interpreted by the presentation service, this memo does not specify their structure. If the DIS version of association control is being used, then use of an OBJECT IDENTIFIER will suffice. If the IS version is being employed, then application-entity titles consist of two parts: an application-process title and an application-entity qualifier. It is suggested that the AP-Title use an OBJECT IDENTIFIER and that the AE-Qualifier use NULL. This memo requires the following mapping rules: 1. The service name for an OSI application-entity using the mechanisms proposed by this memo is: <designator> "-" <qualifier> where <designator> is a string denoting either domain name or a 32-bit IP address, and <qualifier> is a string denoting the type of application-entity desired, e.g., "gonzo.twg.com-mgmtinfobase" 2. Any locally defined mapping rules may be used to map the service designation into an application-entity title. 3. The application-entity title is then mapped into a presentation address, with uninterpreted transport, session, and presentation selectors, and one or more network addresses, each containing: -the 32-bit IP address resolved from the <designator> portion of the service name, - a set indicating which transport services are availableRose [Page 23]RFC 1085 ISO Presentation Services December 1988 at the IP address, - the 16-bit port number resolved from the <qualifier> portion of the service name (using the Assigned Numbers document), and - optionally, a presentation selector, which is an uninterpreted sequence of octets. The method by which the mappings are obtained are straight-forward. The directory services element employs the Domain Name System along with a local table which may be used to resolve the address employing local rules. In the simplest of implementations, the DNS is used to map the <designator> to an IP address, and to fill-in the set of transport services available at the IP address. The port number is found in a local table derived from the current Assigned Numbers document. Finally, the presentation selector is empty. A more ambitious implementation would use a local table to perhaps provide a presentation selector. This would be useful, e.g., in "proxy" connections. The network address would resolve to the proxy agent for the non-IP device, and the presentation selector would indicate to the proxy agent the particular non-IP device desired. This implies, of course, that the local table and the proxy agent bilaterally agree as to the interpretation of each presentation selector.12. Remarks To begin, if one really wanted to implement ISO applications in a TCP/IP-based network, then the method proposed by [RFC1006] is the preferred method for achieving this. However, in a constrained environment, where it is necessary to host an application layer entity with a minimal amount of underlying OSI infrastructure, this memo proposes an alternative mechanism. It should be noted that an OSI application realized using this approach can be moved directly to an [RFC1006]-based environment with no modifications. A key motivation therefore is to minimize the size of the alternate underling infrastructure specified by this memo. As more and more presentation services functionality is added, the method proposed herein would begin to approximate the ISO presentation protocol. Since this in contrary to the key motivation, featurism must be avoided at all costs.Rose [Page 24]RFC 1085 ISO Presentation Services December 198813. Acknowledgements Several individuals contributed to the technical quality of this memo: Karl Auerbach, Epilogue Technologies Joseph Bannister, Unisys Amatzia Ben-Artzi, Sytek Stephen Dunford, Unisys Lee Labarre, MITRE Keith McCloghrie, The Wollongong Group Jim Robertson, Bridge Communications Glenn Trewitt, Stanford University14. References [ISO7498] Information Processing Systems - Open Systems Interconnection, "Basic Reference Model", October, 1984. [ISO8509] Information Processing Systems - Open Systems Interconnection, " Service Conventions". [ISO8650] Information Processing Systems - Open Systems Interconnection, " Protocol Specification for the Association Control Service Element (Final Text of DIS 8650)", January, 1988. [ISO8822] Information Processing Systems - Open Systems Interconnection, " Connection Oriented Presentation Service Definition (Final Text of DIS 8822)", April, 1988. [ISO8823] Information Processing Systems - Open Systems Interconnection, " Connection Oriented Presentation Protocol Specification (Final Text of DIS 8822)", April, 1988. [ISO8824] Information Processing Systems - Open Systems Interconnection, " Specification of Abstract Syntax Notation One (ASN.1)", December, 1987. [ISO8825] Information Processing Systems - Open Systems Interconnection, "Specification of basic encoding rules for Abstract Syntax Notation One (ASN.1)", December, 1987. [ISO9072/2] Information Processing Systems - Text Communication MOTIS, " Remote Operations Part 2: ProtocolRose [Page 25]RFC 1085 ISO Presentation Services December 1988 Specification (Working Document for DIS 9072/2)", November, 1987. [RFC768] Postel, J., "User Datagram Protocol", RFC 768, USC/ISI, 28 August 1980. [RFC791] Postel, J., "Internet Protocol - DARPA Internet Program Protocol Specification", RFC 791, USC/ISI, September 1981. [RFC793] Postel, J., "Transmission Control Protocol - DARPA Internet Program Protocol Specification", RFC 793, USC/ISI, September 1981. [RFC1006] Rose, M., and D. Cass, "ISO Transport 1 on Top of the TCP Version: 3", Northrop Research and Technology Center, May 1987.Appendix A:Abstract Syntax Definitions RFC1085-PS DEFINITIONS ::= BEGIN PDUs ::= CHOICE { connectRequest ConnectRequest-PDU,
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -