1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 ) TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU).4%2!4%$G0G03%26)#%3G0G0$)4!,G0G0.%47/2+G0 )3$.G93%26)#%G0G0#!0!“),)4)%34%,%3%26)#%3G0G03500/24%$G0G0“9G0G0!.G0G0)3$. -)8%$G0-/$%)45G134G0G0RecommendationG0G0) (Extract from the “LUEG0“OOK)NOTES1 ITU-T Recom
2、mendation I.241.4 was published in Fascicle III.7 of the Blue Book. This file is an extract fromthe Blue Book. While the presentation and layout of the text might be slightly different from the Blue Book version, thecontents of the file are identical to the Blue Book version and copyright conditions
3、 remain unchanged (see below).2 In this Recommendation, the expression “Administration” is used for conciseness to indicate both atelecommunication administration and a recognized operating agency. ITU 1988, 1993All rights reserved. No part of this publication may be reproduced or utilized in any fo
4、rm or by any means, electronic ormechanical, including photocopying and microfilm, without permission in writing from the ITU.Fascicle III.7 - Rec. I.241.4 1Recommendation I.241.4Fascicle III.7 - Rec. I.241.4TELESERVICES SUPPORTED BY AN ISDN: MIXED MODE(Melbourne, 1988)4 Mixed modeThe prose definiti
5、on of the mixed mode service is an extract of Recommendation F.230.4.1 DefinitionThis service provides combined text and facsimile communication for end-to-end transfer of documentscontaining mixed information of text and fixed images. The high layer attributes are based on the CCITTRecommendations
6、for Teletex and Telefax 4.4.2 DescriptionFor further study.4.3 ProceduresFor further study.4.4 Network capabilities for chargingThis Recommendation does not cover charging principles. Future Recommendations in the D-Series areexpected to contain that information.It shall be possible to charge the su
7、bscriber accurately for the service.4.5 Interworking requirementsFor further study.4.6 Interaction with supplementary servicesFor further study.4.7 Attributes and values of attributes of the mixed mode servicea) LOW LAYER ATTRIBUTESInformation transfer attributesCircuit-mode bearer capability Packet
8、mode bearer capability1. Information transfer mode circuit packet2. Information transfer rate 64 kbit/s maximum throughput of a givenvirtual circuit is less than or equalto the maximum bit rate of theuser information access channeland the throughput class of thevirtual circuit3. Information transfe
9、r capability unrestricted (Note 1) unrestricted4. Structure unstructured (Note 2) service data unit integrity5. Establishment ofcommunicationdemand demand (VC), permanent (PVC)6. Symmetry bidirectional symmetric bidirectional symmetric7. Communication configuration point-to-point point-to-point2 Fas
10、cicle III.7 - Rec. I.241.4Access attributesCircuit-mode bearer capability Packet-mode bearer capability8. Access channel: B for user informationD for signallinguser information over virtualcircuit within B- or D-channel.When D-channel is used,maximum packet size and qualityof service may be restrict
11、ed.Signalling may be provided via D-channel and/or virtual circuitwithin B-channel (Note 3)9. Access protocol9.1 Signalling access protocollayer 1:Rec. I.430/I.431 Rec. I.430/I.4319.2 Signalling access protocollayer 2:Rec. I.440/I.441 Rec. I.440/I.441, X.319.3 Signalling access protocollayer 3:Rec.
12、I.450/I.451 Rec. I.450/I.451, X.319.4 Information access protocollayer 1:Rec. I.430/I.431 Rec. I.430/I.4319.5 Information access protocollayer 2:Rec. X.75 (SLP) Rec. X.25 (LAPB)9.6 Information access protocollayer 3:ISO 8208 Rec. X.25 (PLP)b) HIGH LAYER ATTRIBUTES10. Type of user information : mixed
13、 mode11. Layer 4 protocol functions: X.224, X.21412. Layer 5 protocol functions: X.225, X.21513. Layer 6 protocol functions: T.61, X.226, X.21613.1 Resolution pixels per inch (ppi): 300 300240 240400 400 optional,600, 120014. Layer 7 protocol functions: T.501, T.522, T.561c) GENERAL ATTRIBUTES15. Su
14、pplementary services provided: for further study16. Quality of service: for further study17. Interworking possibilities: ISDN Teletex, ISDN Telefax 4(others for further study)18. Operational and commercial: for further studyNote 1 - The interworking arrangements with networks having restricted 64 kb
15、it/s information transfercapability require further study.Note 2 - Even if no structure is required the network may provide 8 kHz integrity.Note 3 - User information transferred via virtual channel on the D-channel is for further study.Fascicle III.7 - Rec. I.241.4 34.8 Recommended support of mixed
16、mode by an ISDNa) Overall support1: Ab) Variation of non-dominant attributes:1) Information transfer mode circuit: A packet: A2) Establishment Symmetry Communication Support1of communication configuration_ _demand bidirectional pt-pt Esymmetric3) AccessSignalling and OAM(Note 1)User informationSuppo
17、rtChannel and rate Protocols Channel and rate ProtocolsCircuit modeD(16) I.430, I.440, I.441,I.450, I.451(Note 2)B(64) I.430,X.75 (SLP),ISO 8208AD(64) I.431, I.440, I.441,I.450, I.451(Note 2)B(64) I.431,X.75 (SLP),ISO 8208APacket modeD(16) I.430, I.440, I.441,I.450, I.451, X.31B(64) or D (16) I.430,
18、X.25 LAPB,X.25 (PLP)FSD(64) I.431, I.440, I.441,I.450, I.451, X.31B(64) I.431,X.25 LAPB,X.25 (PLP)FSVC in B(64) for further study B(64) for further study FSNote 1 - Definition of protocols for OAM is for further study.Note 2 - Demand services only. Others are for further study.4.9 Dynamic descriptionThe circuit mode dynamic description appears in Recommendation I.220.1The definition of E (essential) and A (additional) can be found in Recommendation I.240.
