1、I CEPT T/CD*O4-04* 83 E 2326414 0003696 O I - T/CD 04-04 E Page 1 Recommendation T/CD 04-04 E (Cannes 1983) concerning the requirements for Permission to Connect non-PTT equipment to Public Data Networks using the X.25 interface Recommendation proposed by the Working Group T/WG 10 “Data Communicatio
2、n” (CD) Text of the Recommendation adopted by the “Telecommunications” Commission: “The European Conference of Post and Telecommunications Administrations, Considering - that Public Data Networks are implemented or will be implemented in the future; - that harmonization of requirements for Permissio
3、n to Connect non-PTT equipment is essenth; - the studies carried out within the framework of Question CD5 and - Recommendation T/SF 13, specifying the administrative procedure for approvals. Recommends that the technical information specified in the Annex must be obtained in order that Administratio
4、ns may determine whether Permission to Connect to Public Data Networks may be given.” 0 Scope: The actual purpose of this document is to list the questions to be answered by the manufacturer who asks for Permission to Connect a DTE to a packet switched data transmission service by dedicated circuit.
5、 This document does not cover the access to a packet network through circuit switched data transmission services. Note: The Annex is an integral part of the Recommendation. Edition of March 15, 1986 CEPT T/CD*04-04*E 3 2326414 0003697 2 -1 1 . 1.1. 1.2. 1.3. 1.4. 2 . 2.1. 2.1.1. 2.1.2. 2.1.3. 2.1.4.
6、 2.1.5. 2.1.6. 2.1.7. 2.1 . 8. 2.2. 2.2.1. 2.2.2. 3 . 3.1. 3.1.1. 3.1.2. 3.1.3. 3.2. 3.2.1. 3.2.2. 3.2.3. 3.2.4. 3.2.5. 3.2.6. 3.2.7. 3.2.8. 3.2.9. 3.3. 3.3.1. 3.3.2. 3.3.3. 3.3.4. 3.3.5. 3.3.6. 3.3.7. 3.3.8. 3.3.9. 3.3.10. Contents GENERAL ASPECTS . General informations Safety aspects . Radio inter
7、ference suppression Identification and signature PHYSICAL LEVEL Inierfaces used . Data signalling rate . Mode of operation . Interchange circuits V-series for X.2lbis interjke Common aspects to all Data Transmission Services . Interchange circuits X-series for X.21 interface . Electrical characteris
8、tics . Mechanical characteristics of the DTE interface connector Testloops . Specific aspects to direct connection to packet switched data transmission service Use of V-series circuits for X.2lbis interface Use of X-series circuits for X.21 interface . FRAMELEVEL General Frame structure Frame level
9、parameters . LAP protocol . DTE time-outs and resulting actions Frame level resetting by the DTE . Frame level resetting by the DCE . Link disconnection by the DTE Link disconnection by the DCE I-frame transmission by the DTE . I-frame reception by the DTE DTE reaction in case of error LAPB protocol
10、 . DTE time-outs and resulting actions Link set-up by the DTE . Link set-up by the DCE . Frame level resetting by the DTE . Frame level resetting by the DCE . Link disconnection by the DTE Link disconnection by the DCE I-fame transmission by the DTE . I-frame reception by the DTE DTE reaction in cas
11、e of error Implemented protocol Link set-up by the DTE . Edition of March 15. 1986 . .a . TfCD 04-04 E Page 3 . a. Page 5 5 5 6 6 7 7 7 7 7 8 9 10 11 12 13 13 13 14 14 14 14 14 15 15 15 15 15 16 16 16 16 17 18 18 18 18 18 18 18 19 19 19 20 CEPT T/CD*04-04*E 83 W 2326414 0003678 4 E T/CD.04-04 E Page
12、 4 4 . 4.1. 4.1.1. 4.1,2. 4.1.3. 4.2. 4.2.1. 4.2.2. 4.2.3. 4.2.4. 4.2.5. 4.2.6. 4.3. 4.3.1. 4.3.2. 4.3.3. 4.3.4. 4.3.5. 4.3.6. 4.3.7. 4.3.8. 4.3.9. 4.3.10. PACKET LEVEL . General Packet level parameters . Logical channel numbering Facilities . Specific control procedures for switched virtual circuit
13、s DTE time-outs and resulting actions Generation of call request packet by the DTE Handling of incoming call packet by the DTE Clearing by the DTE Clearing by the DCE DTE reaction in case of error Common control procedures to permanent virtual circuits and switched virtual circuits DTE time-outs and
14、 resulting actions Reset by the DTE . Reset by the DCE . Data Packet transmission and reception Interrupt by the DTE Interrupt by the DCE Restart by the DTE . Restart by the DCE . DTE reaction in case of error Relations between frame and packet levels . Page 21 21 21 21 22 24 24 24 25 26 26 26 27 27
15、 27 27 27 28 28 28 28 29 29 . - CEPT T/CD*04-OY*E 83 E 2326414 0003b99 b W TJCD 04-04 E Page 5 1. GENERAL ASPECTS 1.1. General Informations DTE Type: Factory No. : Manufacturer (name, address, telephone and telex number) : Agent (name, address, telephone and telex number) : 1.2. Safety aspects Indic
16、ate ail recognized national and/or international safety standards to which the DTE conforms. Indicate classes/types of equipment referred to in these standards where applicable. Statements of complience with the above standards is taken to be legally binding. Has the DTE already received safety appr
17、oval according to the above standards? NO n o If YES, indicate names, addresses of all approving authorities aad approval code numbers which the DTE has received: * Cross applicable. Edition of March 15, 1986 CEPT T/CD*04-04*E 83 2326434 0003700 9 I T/CD 04-04 E Page 6 1.3. Radio interference suppre
18、ssion Indicate all recognized national and/or international standards to which the DTE conforms. Statements of complience with the above standards is taken to be legally binding. “ Has the DTE already received appropriate approvals according to the above standards? YES ri NO n * If YES, indicate nam
19、es, adresses of approving authorities and approval code numbers which the DTE has received : 1.4. Identification and signature This questionnaire has been submitted by: Name: Date: Signature: * Cross applicable. Telephone : Telex : Edition of March 15, 1986 CEPT T/CD*04-04*E 83 = 2326414 O003701 O D
20、ata signalling rate (bitls) 2,400 T/CD 04-04 E Page 7 o 2. PHYSICAL LEVEL 2.1. 2.1.1. Interfaces used Common aspects to aii Data Transmission Services With which CCIT Recommendation does the DTE conform? +* X.2lbis 2.1.2. Data signalling rate 2.1.3. Mode of operation Is the DTE capable of duplex tra
21、nsmission (Le. simultaneous use of circuits T and R or 103 and 104)? * Cross applicable. Edition of March 15, 1986 CEPT T/CD*O4-04*E 83 2326434 0003702 2 T/CD 04-04 E Page 8 2.1,4, Interchange circuits V-series for X.2lbis interface Note: Electrical characteristics according to Recommendation V. 11
22、have been added, as they may be used on a 37-pin connector. * Cross applicable. * This circuit may not be relevant to direct connection to packet switched data transmission service. /- Edition of March 15, 1986 CEPT T/CD*O4-04*E 83 m 232b4L4 0003703 4 m IA IB SB SA * BA BB TJCD 04-04 E Page 9 Indica
23、tion 1 Byte timing Signal element timing 2.1.5. Interchange circuits X-series for X.21 interface Edition of March 15, 1986 CEPT T/CD*04-04*E 83 I 2326434 0003704 b S T/CD 04-04 E Page 1 O 2.1.6. Electrical characteristics 2.1.6.1, Generator The nominal, values are laid down in the relevant CCITT-Rec
24、ommendations. 2.1.6.1,l. Integrated circuit? YES n If YES, indicate type and manufacturer: 2.1.6.1.2. Discrete components? YES n 2,l.G. 1.3. Indicate test results of the following characteristics: Open circuit measurement Binary state O: V Binary state 1: V Test termination measurement Binary state
25、O: Binary state 1: Short-circuit measurement Binary state O: Binary state 1: Power-of measurement Leakage current: * Cross applicable. V V mA mA PA Edition of March 15, 1986 CEPT T/CD*O4-04*E 83 232b414 OOfl3705 8 TICD 04-04 E Page 11 Transition time measirrement O- 1 transition : S 1-0 transition:
26、S 2.1.6.2. Receiver 2.1.6.2.1. Integrated circuit? If YES, indicate type and manufacturer: o 2.1.6.2.2. Discrete components? 2.1.6.2.3. Indicate test results of the foilowing characteristics: Input voltage-current measurement Binary state O: mA Binary state 1: mA DC sensitivity measurement Binary st
27、ate O: mV Binary state 1 : mV 2.1.7. Mechanical characteristics of the DTE inte$ace connector* 15-pin connector (IS0 4903) 25-pin connector (IS0 21 10) 34-pin connector (IS0 2593) 37-pin connector (IS0 4902) * Cross applicable. Edition of March 15, 1986 .- CEPT T/CD*04-04* 43 a 2326434 0003706 T T/C
28、D 04-04 E Page 12 Interface adaptor to be used? YES n If YES, describe the adaptor including circuit diagram: 2.1.8. Test loops Cross loops applied: DTE DCE i * Line J L c no Indicate other loops that can be used by the DTE: * Cross applicable. o Edition of March 15, 1986 -. CEPT T/CD*04-04*E 3 W 23
29、2b4L4 0003707 L T/CD 04-04 E Page 13 2.2. Specific aspects to direct connection to packet switched data transmission service 2.2.1. Use of V-series circuits for X.2lbis interface 2.2.1.1. Under what circumstances does the DTE present circuit 108.1 in the OFF condition? 2.2.1.2. Under what circumstan
30、ces does the DTE present circuit 105 in the OFF condition? 2.2.2. Use of X-series circuits for X.21 interface Under what circumstances does the DTE present circuit C in the OFF condition? e Edition of March 15, 1986 I I i CEPT T/CD*04-04*E 3 S 2326414 0003708 3 T/CD 04-04 E Page 14 3. FRAME LEVEL 3.
31、1. General 3.1.1. Implementedprotocol What protocol is implemented within the DTE? 3.1.2. Frame structure 3.1.2.1. Does the DTE check received frames addresses? 3.1.2.2. What is the minimum number of flags between transmitted frames? 3.1.2.3. What is the minimum number of flags the DTE can accept be
32、tween received frames? 3.1.2.4. Are contiguous flags (Hex7E) sent when no frames are being transmitted? 3.1,2.5. Is the DTE capable of receiving an I-frame containing a non-integral number of octets? 3.1.2.6. Is the DTE capable of transmitting an I-frame containing a non-integral number of octets? 3
33、.1.3. Frame level parameters In the following list of parameters, please indicate the values which can be selected, e.g. lowest, highest, including increments and where applicable, the normal value set: Normal 2,4 kbit/s 4,8 kbit/s 9,6 kbit/s 48 kbit/s Parameters Range In steps of TI (ms) T2 (ms) N1
34、 (in bits) * Cross applicable. Edition of March 15, 1986 O CEPT T/CD*OY-O4*E 83 I 232b414 0003707 5 T/CD 04-04 E Page 10 3.2. LAP protocol 3.2.1. DTE time-outs and resulting actions Please complete tables 3.1. and 3.2. Where appropriate, you may state T1 and/or N2. 3.2.2. Link set-up by the DTE 3.2.
35、2.1. Under what conditions does the DTE initiate the link set-up procedure? I After power-on I I After a DCE link disconnection I After operating system start or restart After a manual command I Others I 3.2.3. Frame level resetting by the DTE 3.2.3.1. Under what conditions does the DTE initiate a f
36、rame level resetting procedure? * I After a DCE frame levei resetting I I When transmission of and I-frame is impossible After receipt of a CMDR response Others * 3.2.4. Frame level resetting by the DCE 3.2.4.1, What action is taken by the DTE upon receipt of a SARM command within the information tr
37、ansfer phase? 3.2.4.2. What action is taken by the DTE upon receipt of a SARM command within the disconnected phase? * Cross applicable. I t i Edition of March 15, 1986 CEPT T/CD*04-04*E 83 = 2326434 0803730 3 TICD 04-04 E Page 16 3,2.5, 3.2.5.1. 3.2.6. 3.2.6.1, 3.2.6.2. 3.2.7. 3.2.7.1. 3.2.7.2. 3,2
38、.7,3, 3.2.7.4. 3.2.7.5. 3.2.7.6. 3.2.7.7. 3,2,7.8. 3.2.8, 3.2.8.1. 3.2.8.2. 3.2.8.3. Linfv disconnection by the DTE Under what conditions does the DTE disconnect the link: After DCE frame level resetting After a manual command Before operating system start Others * Link disconnection by the DCE What
39、 action is taken by the DTE upon receipt of a DISC command within the information transfer phase? What action is taken by the DTE upon receipt of a DISC command within the disconnected phase? I-fiame transmission by the DTE After retransmission of an I-frame and before an acknowledgement for this fr
40、ame is received, are RR and REJ responses with a F bit set to O ignored? Does the same apply to N (R) within I-frames? If yes, is the N (R) validity checked? Upon receipt of an acknowledgement in a REJ response, does the DTE discard the concerned frames from the transmission buffer? Does the DTE abo
41、rt a frame if, during its retransmission, an acknowledgement for this frame is received? Does the DTE abort a frame if, during its transmission, a REJ response concerning a previously transmitted frame is received? Does the DTE perform any frame level action when there is no traffic on the link? If
42、yes, which frame is transmitted and how often? I-frame reception by the DTE Does the updating of receive state variable V (R) result systematically in the transmission of a RR response by the DTE? Does the DTE delay the acknowledgements in order to combine them? If yes, in what situations and to wha
43、t degree? * Cross applicable. CEPT T/CD*OY-O4*E 3 W 2326434 00037LL 3 = Event Incorrect command length T/CD 04-04 E Page 17 Action Report* 3.2.8.4. Is a time-out implemented within the DTE for transmission of acknowledgement? 3.2.8.5. What is the value of this time-out? 3.2.8.6. Is the N (R) of an I
44、-frame or RR response set immediately prior to transmission or when the frame is placed on the transmission queue? 3.2.8.7. Does the DTE transmit REJ, RNR, CMDR responses? 3.2.8.8. If yes, in what cases (RNR and CMDR)? 3.2.8.9. Are there any cases where correct frames are ignored? 3.2.8.10. If yes,
45、what are those cases? 3.2.9. DTE reaction in case of error 3.2.9.1. What action is taken by the DTE on occurence of the foilowing events and which events cause a report to be generated? Incorrect response length Unknown command Unknown response l I I Receipt of CMDR response I I I _ Incorrect N (R)
46、N (S) outside the receive window Response with F = 1 not expected l I I Unknown address I I I 3.2.9.2. Does the DTE interpret and report the information field of a CMDR response? * Cross applicable. Edition of March 15, 1986 CEPT T/CD*04-04*E 83 O 2326434 0003732 5 W T/CD 04-04 E Page 18 3.3. LAPB p
47、rotocol 3.3.1. DTE time-outs and resulting actions Please complete tables 3.3. and 3.4. Where appropriate, you may state T1 and/or N2. 3.3.2. Link set-up by the DTE 3.3,2.1. What action is taken by the DTE upon receipt of DM response after transmission of the SABM command? 3.2.2.2. Under what condit
48、ions does the DTE initiate the link set-up procedure? I After power-on I I After a DCE link disconnection After operating system start or restart * After a manual command Others 3.3.3. Link set-up by the DCE 3.3.3.1. Under what conditions does the DTE answer to a SABM command with a DM response? 3.3
49、.3.2. Does the DTE use the DM response to request a set mode command from the DCE? 3.3.4. Frame level resetting by the DTE 3.3.4,l. Under what conditions does the DTE initiate a frame level resetting procedure? I After a DCE frame level resetting l I When transmission of and I-frame is impossible 3.3.5, Frame level resetting by the DCE 3.3.5.1. What action is taken by the DTE on receipt of SABM command within the information transfer phase? 3.3.5,2. What action is taken by the DTE on receipt of SABM command within the disconnected phase? 3.3,
