1、INTERNATIONAL STANDARD lSO/lEC 15507 First edition 1997-12-01 Information technology - Telecommunications and information exchange between systems - Private Integrated Services Network - Inter-exchange signalling protocol - PINX clock synchronization Technologies de /information - T .- The following
2、 two operations shall apply to SYNC-SIG 3ynchronizationRequest := Synchronizationlnfo - - SynchronizationReqArg := OPERATION ARGUMENT SynchronizationReqArg RESULT SynchronizationReqRes ERRORS unspecified OPERATION ARGUMENT SynchronizationlnfoArg SEQUENCE action Action, argExtension ArgExtension OPTI
3、ONAL SynchronizationReqRes := SynchronizationlnfoArg := SEQUENCE action Action, response BOOLEAN, - TRUE = yes, FALSE = no argExtension ArgExtension OPTIONAL SEQUENCE stateinfo INTEGER freerunning (0), idle (l), argExtension ArgExtension OPTIONAL Action := INTEGER enslavement (0) holdon (1) ArgExten
4、sion := CHOICE extension l IMPLICIT Extension, sequOfExtn 2 IMPLICIT SEQUENCE OF Extension synchronizationRequest SynchronizationRequest := 78 synchronizationlnfo Synchronizationlnfo := 79 unspecified Unspecified := 1008 Unspecified := ERROR PARAMETER Extension END - of Synchronization-Operations IS
5、OLIEC 15507:1997 (E) OISO/IEC 6.3.2 Information elements 6.3.2.1 Facility information element The operations defined in 6.3.1 shall be coded in the Facility information element in accordance with ISO/IEC 11582. When conveying the invoke APDU of the operations defined in 6.3.1, the destinationEntity
6、data element of the NFE shall contain value endPINX and the interpretation APDU shall either be omitted or be included with the value rejectAnyUnrecognisedInvokePdu. 6.3.2.2 Other information elements Any other information element (e.g. Called party number) shall be coded in accordance with ISO/IEC
7、11582. 6.3.3 Messages The transport mechanism is based on call-independent signalling connection (connection-oriented).The Facility information element shall be conveyed in the FACILITY message as specified in clause 10 of ISO/IEC 11582. 6.4 State definitions The procedures for each PINX in the netw
8、ork are written in terms of the following conceptual states existing within the SYNC- SIG control entity in that PINX. 6.4.1 States at the Requesting PINX 6.4.1.1 SYNC-Idle This state exists when the connection for synchronization is not established (exchange of information is not possible). 6.4.1.2
9、 SYNC-Active This state exists when the connection for synchronization is established (exchange of information is possible). 6.4.1.3 SYNC-Wait This state exists when the connection is established and a synchronizationRequest invoke APDU is sent to the Destination PINX and the response is not yet rec
10、eived. 6.4.2 States at the Destination PINX 6.4.2.1 SYNC-Idle This state exists when the connection for synchronization is not established (exchange of information is not possible). 6.4.2.2 SYNC-Active This state exists when the connection for synchronization is established (exchange of information
11、is possible). 6.5 Signalling procedures Annex B contains examples of message sequences of the signalling procedures. 6.51 Actions at the Requesting PINX The SDL representation of procedures of the Requesting PINX is shown in C. 1 of annex C. Note - Choice of information to request by the Requesting
12、PINX and actions in the Synchronization Entity on receipt or absence of response from the Destination PINX are to be made in confxmance with ISOAEC 11573 and are outside the scope of this International Standard. 6.5.1.1 Normal procedures In state SYNC-Idle, on request of the Synchronization Entity t
13、he SYNC-SIG Control entity shall invoke SYNC-SIG towards an adjacent PINX. The Requesting PINX shall act as an Originating PINX and establish a call-independent signalling connection (connection-oriented) towards the Terminating PINX using the specific called party number given by the Synchronizatio
14、n entity. The SYNC-SIG Control entity shall inform the Synchronization Entity when the connection is established and enter state SYNC-Active. Only the call reference of this call-independent signalling connection shall be used to transport SYNC-SIG operations. On request of the Synchronization Entit
15、y, the SYNC-SIG Control entity releases the connection towards the adjacent PINX and SYNC-SIG enters state SYNC-Idle. In states SYNC-Wait and SYNC-Idle, requests from the Synchronization Entity for sending information to the adjacent PINX are ignored. In SYNC-Active state, if the Synchronization Ent
16、ity requests for sending information not requiring a response (free-running, idle), the Requesting PINX shall send a synchronizationInfo invoke APDU, and remain in state SYNC-Active. In state SYNC-Active, if the Synchronization Entity requests for sending information requiring a response from the De
17、stination PINX (enslavement or holdon request), the Requesting PINX shall send a synchronizationRequest invoke APDU, start timer 4 OISO/IEC ISO/IEC 15507:1997 (E) Tl, and enter state SYNC-Wait. In state SYNC-Wait, on receipt of the synchronizationRequest return result APDU from the Destination PINX,
18、 the Requesting PINX shall convey the result to the Synchronization Entity, stop timer Tl, and enter state SYNC-Active. In state SYNC-Wait, if the connection is released, the Requesting PINX shall inform its Synchronization Entity, stop timer Tl, and enter state SYNC-Idle. In state SYNC-Active, if t
19、he connection is released by the adjacent PINX, the Requesting PINX shall inform Synchronization Entity and enter state SYNC-Idle. 6.5.1.2 Exceptional procedures In state SYNC-Wait, on receipt of the synchronizationRequest return error or reject APDU from the Destination PINX, the Requesting PINX sh
20、all inform the Synchronization Entity, stop timer Tl, and enter state SYNC-Active. If timer Tl expires in state SYNC-Wait, the Requesting PINX shall inform the Synchronization Entity, and enter state SYNC-Active. 6.5.2 Actions at the Destination PINX The SDL representation of procedures of the Desti
21、nation PINX is shown in C.2 of annex C. Note - Choice of response to send by the Destination PINX and actions in the Synchronization Entity on receipt of requests from the Requesting PINX are to be made in conformance with ISO/IEC 11573 and are outside the scope of this International Standard. 6.5.2
22、1 Normal procedures The call reference of the call-independent signalling connection that was established by the Requesting PINX shall be used to transport SYNC-SIG operations. The SYNC-SIG Control entity shall inform the Synchronization Entity when the connection is established and enter state SYN
23、C-Active. In state SYNC-Active, on receipt of the synchronizationRequest invoke APDU or synchronizationbifo invoke APDU from the Requesting PINX, the Destination PINX shall convey the information to the Synchronization Entity and remain in state SYNC- Active. In state SYNC-Active, if the Synchroniza
24、tion Entity requests sending a response to a synchronizationRequest invoke APDU, the Destination PINX shall send a synchronizationRequest return result APDU to the Requesting PINX and remain in state SYNC-Active. On request of the Synchronization Entity, the Destination PINX shall release the connec
25、tion towards the Requesting PINX and enter state SYNC-Idle. In state SYNC-Active, if the connection is released by the adjacent PINX, the Destination PINX shall inform the Synchronization Entity and enter state SYNC-Idle. 6.5.2.2 Exceptional procedures If a synchronizationRequest invoke APDU cannot
26、be accepted a synchronizationRequest return error APDU shall be returned. 6.6 Impact of interworking with public ISDNs Not applicable. 6.7 Impact of interworking with non-ISDNs Not applicable. 6.8 Protocol interactions between Synchronization and supplementary services and ANPs Not applicable. 6.9 Parameter values (timers) 6.9.1 Timer Tl Timer Tl operates at the Requesting PINX in state SYNC-Wait. Its purpose is to protect against the absence of a response to the synchronizationRequest invoke APDU. Timer Tl shall have a value not less than 15 s.
