For Information: Change Requests on HSCSD Initial Synchronization

Transcription

1 ETSI TC SMG # 22 Plenary Meeting Kristiansand, Norway 9th - 13th June 1997 Tdoc SMG 417/ 97 Source: Ericsson Agenda Item: 6.4 For Information: Change Requests on HSCSD Initial Synchronization Introduction: The following CRs were agreed in principle during the SMG4 TA/IWF group session but have only been sent out via on the 04/06/97 to SMG4 delegates. Therefor they are presented here for information only. Background: In the TA/IWF group session during the SMG4 in Bunratty, May 1997, Ericsson presented a discussion paper (SMG4 Tdoc 97P066) pointing out a problem with the initial synchronisation in case of transparent services using more than one time slot. The problem was acknowledged by the TA/IWF group. The TA/IWF group also agreed to correct the situation by exchanging the substream numbers and multiframe alignment information during the period when otherwise the 1/OFF synchronisation pattern is exchanged. Ericsson and Nokia were asked to produce the necessary CRs to reflect this change. However, due to lack of time, the CRs were not presented during the SMG4 meeting. The two CRs submitted to SMG reflect, we believe, the changes that were agreed. Ericsson considers this issue to be critical for the implementation of HSCSD transparent services. SPEC VERS CR RE V PH AS E CAT SUBJECT STC_DOC strategic A C Initial synchronization for HSCSD 97p156 Yes A C Initial synchronization for HSCSD 97p157 Yes Other Comments: Number of Pages:

2 Blank Page

3 CHANGE REQUEST No. A023 Technical Specification GSM version Submitted to SMG for approval without presentation ("non-strategic") [ ] with presentation ("strategic") [ x ] Status at SMG [ ]: Approved [ ] Rejected [ ] Postponed [ ] Phase 1: [ ] Phase 2: [ ] Phase 2+: [x] Work item: HSCSD Other phase(s) affected: [ ] If yes, linked CR(s): Proposed change affects: SIM [ ] ME [ ] Network [x] Source: Ericsson Date: Subject: Initial synchronization for HSCSD Category: F - Correction [ ] A - Corresponds to a Phase 2 correction [ ] B - Addition of Feature [ ] C - Functional modification of Feature [X] D - Editorial modification [ ] Reason for change: The initial synchronisation between the MS and the IWF when more than 1 channel are used is modified such that the two entities can align the received substreams before receiving data. Sections affected, and additional explanation of details of change (if needed): Section 8.1. If other core Specifications are affected, necessary (and attached) Joint Crs: A Affects (possibly): MS Test Specifications [ ] BSS Test Specifications [ ] O&M Specifications [ ] Attached CRs?: Cross Phase Compatibility: Change affects operation of: Phase 1 MS in Phase 2(+) NW [ ] Phase 2(+) MS in Phase 1 NW [ ] CR to attached: Change affects operation of: Phase 1 SIM in Phase 2(+) ME[ ] CR to attached: Other comments: Phase 2(+) SIM in Phase 1 ME [ ] CR to attached:

4 Page 2 CR to Draft prets (GSM Version 5.3.0): November Synchronization of the Traffic Channel As long as there is no connection between the traffic channel and the interface to the TE this interface must be terminated in the appropriate way. Prior to exposing the traffic channel of a GSM PLMN connection to transmission of user data, the controlling entities of the connection have to assure of the availability of the traffic channel. This is done by the so called synchronization process: - starting on the indication of "physical connection established" resulting from the PLMN inherent outband signalling procedure. This indication is given on reception of the message CONNECT in case of MOC, on reception of the message CONNACK in case of MTC and on reception of the message MODIFY COMPLETE in case of in-call modification. - ending by indicating the successful execution of this process to the controlling entity, which then takes care of the further use of the inband information (data, status). With respect to the TAF for the transparent bearer capability support the synchronization procedure is as follows: - sending of synchronization pattern 1/OFF (all data bits "1" / all status bits "OFF", all E-bits "1") to the IWF. In multislot cases and transparent operation, the synchronisation pattern sent is 1/OFF with the exception of the bit positions S1, X, S3, and S4 which contain the substream number and multiframe alignement pattern (Ref. GSM TS 04.21).; - searching for detection of the synchronization pattern 1/OFF received from the IWF. The value of the bits E4-E7 shall not be checked. In multislot cases and transparent operation, the synchronisation pattern received is 1/OFF with the exception of the bit positions S1, X, S3, and S4 which contain the substream number and multiframe alignement pattern (Ref. GSM TS 04.21).; - holding CT106, 107 and 109 in the OFF condition; When the synchronisation pattern 1/OFF from the IWF has been recognized as a steady state (see note 1) the TAF continues sending the synchronization pattern 1/OFF to the IWF unless a timer T (=500ms) expires. NOTE 1: - An idle frame sent by the BSS and received by the MS has the same pattern as the synchronization pattern 1/OFF. - At the moment when the message CONNECT (MOC) or CONNACK (MTC) is received at the MS, it is guarantied that this pattern is received from the MSC/IWF with the exception of a loss of frame synchronization on the Abis interface. - The handling of frame stealing in case of 2400 bit/s full rate data channels is implementation dependent. From this time the filtering process according to section 8.2 applies and the information on the receiving lines CT106 and CT109 from the IWF are directly mapped to the respective sending lines. The condition on CT107 will be changed from "OFF" to "ON", the data bits received from the IWF are mapped to CT104, and CT103 is mapped to the data bits sent towards the IWF. During the synchronization process described above i.e. while the synchronization pattern is being sent by the MT, the MT will not send the V.110 frame structure to the ISDN terminal. Once the timer T expires the synchronization pattern will continue to be transmitted from the MT to the IWF, however, the MT will start sending the V.110 frames received from the IWF to the ISDN terminal. The MT will start looking for the ISDN frame alignment to be received from the ISDN terminal. On recognizing frame alignment the MT will cease sending its synchronization pattern to the IWF and connect the ISDN terminal through to the IWF. With respect to the TAF for non-transparent bearer capability support the synchronization procedure is as follows: - initiating the RLP link establishment by sending a RLP-SABM across the radio interface.

5 Page 3 CR to Draft prets (GSM Version 5.3.0): November holding CT106, 107, 109 in the OFF condition. When the RLP link has been established, CT107 will be changed from "OFF" to "ON". From this time the information from/to the RLP, including status changes, will be mapped by the L2R entity applicable to the particular bearer capability. The MT will not send V.110 frame structure to the ISDN terminal and will not start looking for ISDN frame alignment to be received from the ISDN terminal unless the RLP link has been established. On recognizing frame alignment the information from/to the RLP will be mapped by the L2R entity. It should be noted that in a GSM PLMN V.-series and X.-series interfaces are only supported in full duplex mode. Thus the call control phase can be mapped almost completely to the signalling procedure (the S- bits during the call control phase are irrelevant). However, the "ready for data" condition (i.e. CT 106/109, in the case of V.-series interface, and I-circuit, in the case of X.-series interface) is derived directly from the traffic channel (see also filtering of channel information).

6 CHANGE REQUEST No. A029 Technical Specification GSM version Submitted to SMG for approval without presentation ("non-strategic") [ ] with presentation ("strategic") [ X ] Status at SMG [ ]: Approved [ ] Rejected [ ] Postponed [ ] Phase 1: [ ] Phase 2: [ ] Phase 2+: [x] Work item: HSCSD Other phase(s) affected: [ ] If yes, linked CR(s): Proposed change affects: SIM [ ] ME [ ] Network [x] Source: Ericsson Date: Subject: Initial synchronization for HSCSD Category: F - Correction [ ] A - Corresponds to a Phase 2 correction [ ] B - Addition of Feature [ ] C - Functional modification of Feature [x] D - Editorial modification [ ] Reason for change: The initial synchronisation between the MS and the IWF when more than 1 channel are used is modified such that the two entities can align the received substreams before receiving data. Sections affected, and additional explanation of details of change (if needed): Sections , If other core Specifications are affected, necessary (and attached) Joint Crs: A Affects (possibly): MS Test Specifications [ ] BSS Test Specifications [ ] O&M Specifications [ ] Attached CRs?: Cross Phase Compatibility: Change affects operation of: Phase 1 MS in Phase 2(+) NW [ ] Phase 2(+) MS in Phase 1 NW [ ] CR to attached: Change affects operation of: Phase 1 SIM in Phase 2(+) ME[ ] CR to attached: Other comments: Phase 2(+) SIM in Phase 1 ME [ ] CR to attached:

7 Page 2 CR to Draft prets (GSM version 5.2.1): April Establishment of end-to-end terminal synchronizations Prior to exposing the traffic channel of a PLMN connection to transmission of user data, the controlling entities of the connection have to assure of the availability of the traffic channel. This is done by a so called synchronizations process: - starting on the indication of "physical connection established" resulting from the PLMN-inherent outband signalling procedure. This indication is given on sending the message CONNECT in case of MOC, CONNECT ACKNOWLEDGEMENT in case of MTC and MODIFY COMPLETE (which is sent after reception of the ASSIGN COMPLETE message) in case of in-call modification. - ending by indicating the successful execution of this process to the controlling entity, which then takes care of the further use of the inband information (data, status). Network interworking within an MSC/IWF is concerned with the terminating side (to the MS) and the transit side (to the fixed network) of a connection. Both sides have to be treated individually related to the synchronizations process. With respect to the terminating side the procedure is as follows: - sending of synchronizations pattern 1/OFF (all data bits"1"/all status bits "OFF") to the MS using the RA1/RA2 rate adaptation function. In multislot cases and transparent operation, the synchronisation pattern sent is 1/OFF with the exception of the bit positions S1, X, S3, and S4 which contain the substream number and multiframe alignement pattern (Ref. GSM TS 04.21). - searching for detection of the synchronizations pattern 1/OFF from the MS within valid V.110 frames. This implies that the E1, E2 and E3 bit of the V.110 frame shall be checked for the appropriate user rate in order to distinguish the synchronization pattern from the BSS idle data frame. In multislot cases and transparent operation, the synchronisation pattern received is 1/OFF with the exception of the bit positions S1, X, S3, and S4 which contain the substream number and multiframe alignement pattern (Ref. GSM TS 04.21). With respect to the transit side the procedure is as follows: - holding the modem interchange circuits (with the exception of CT108) in the OFF condition until timer T (see below) expires, when they are switched to ON. When the synchronisation pattern1/off from the MS has been recognized as a steady state, the MSC/IWF continues sending the synchronizations pattern 1/OFF to the MS unless a timer T (= 500 ms) expires. From this time, after the expiration of the timer T of each allocated traffic channel, the information on CT106 and CT109 from the Local Modem are directly mapped to the Sb and X bits toward the MS. The IWF is allowed to map CT 104 to the data bits sent towards the MS and to map data bits received from the MS to CT 103. Mobile Originated At the start of timer T for each of the allocated traffic channel(s) of the call, i.e. on receipt of the synchronizations pattern from the MS, circuit 108 to the selected modem associated with the connection will be switched from the "OFF" to "ON" condition, thus initiating the auto calling sequence. Mobile Terminated At the start of timer T for each of the allocated traffic channel(s) of the call, i.e. on receipt of the synchronizations pattern from the MS, circuit 108 to the selected modem associated with the connection will be switched from the "OFF" to "ON" condition, thus initiating the establishment of the modem connection. It should be noted that in a GSM-PLMN V.-series and X.-series interfaces are only supported in full duplex mode. Thus the call control phase can be mapped almost completely to the signalling procedure (the S-bits during the call control phase are irrelevant). However, the "ready for data" condition (i.e. CT106/109, in case of V.-series interface, and I-circuit, in case of X.-series interface) is mapped

8 Page 3 CR to Draft prets (GSM version 5.2.1): April 1997 directly to the applicable status bits of a V.110 frame towards the MS (see also filtering of channel control information). *** Next modified section *** Establishment of end-to-end terminal synchronizations Prior to exposing the traffic channel of a PLMN connection to transmission of user data, the controlling entities of the connection have to assure of the availability of the traffic channel. This is done by a so called synchronizations process: - starting on the indication of "physical connection established" resulting from the PLMN-inherent outband signalling procedure This indication is given on sending the message CONNECT in case of MOC, CONNECT ACKNOWLEDGEMENT in case of MTC and MODIFY COMPLETE (which is sent after reception of the ASSIGN COMPLETE message) in case of in-call modification. - ending by indicating the successful execution of this process to the controlling entity, which then takes care of the further use of the inband information (data, status). Network interworking within an MSC/IWF is concerned with the terminating side (to the MS) and the transit side (to the fixed network) of a connection. Both sides have to be treated individually related to the synchronizations process. With respect to the terminating side the procedure is as follows: - sending of synchronizations pattern 1/OFF (all data bits "1"/all status bits "OFF") to the MS using the RA1/RA2 rate adaptation function. In multislot cases and transparent operation, the synchronisation pattern sent is 1/OFF with the exception of the bit positions S1, X, S3, and S4 which contain the substream number and multiframe alignement pattern (Ref. GSM TS 04.21).; - searching for detection of the synchronizations pattern 1/OFF from the MS within valid V.110 frames. This implies that the E1, E2 and E3 bit of the V.110 frame shall be checked for the appropriate user rate in order to distinguish the synchronization pattern from the BSS idle data frame. In multislot cases and transparent operation, the synchronisation pattern received is 1/OFF with the exception of the bit positions S1, X, S3, and S4 which contain the substream number and multiframe alignement pattern (Ref. GSM TS 04.21). In case of interworking to the ISDN "3,1 khz audio" bearer service the synchronization process is as for the PSTN interworking case (see subclause ). In case of interworking to the ISDN unrestricted digital bearer service the following synchronization process has to be performed. When the synchronisation pattern1/off from the MS has been recognised as a steady state, the MSC/IWF continues sending the synchronizations pattern 1/OFF to the MS unless a timer T expires. From this time, after the expiration of the timer T of each allocated traffic channel, the information on the receiving lines from the MS and from the fixed network are directly mapped to the respective sending lines. During the synchronizations process described above, i.e. while the synchronizations pattern is being sent by the MSC/IWF, the MSC/IWF will not send the V110 frame structure to the ISDN transit network. Once timer "T" for each of the allocated traffic channel(s) of the call expires the synchronizations pattern will continue to be transmitted from the MSC/IWF to the MS, however, the MSC/IWF will start sending the V110 frames received from the MS to the ISDN transit network. The MSC/IWF will start looking for the ISDN frame alignment to be received from the ISDN. On recognising frame alignment the MSC/IWF will cease sending its synchronizations pattern to the MS and connect the ISDN through to the MS. It should be noted that in a GSM PLMN V.-series and X.-series interfaces are only supported in full duplex mode. Thus the call control phase can be mapped almost completely to the signalling procedure (the S-bits during the call control phase are irrelevant). However, the "ready for data" condition (i.e. CT106/109, in case of V.-series interface, and I-circuit, in case of X.-series interface) is derived directly from the traffic channel (see also filtering of channel control information).