The SERCNET-PSS Gateway provides access from SERCNET to PSS and PSS to SERCNET. It functions as a straight through connection between the networks, ie it is protocol transparent. It operates as a Transport Level gateway, in accordance with the Yellow Book Transport Service. For X29, the most widely used terminal protocol, which does not use the Yellow Book Transport Service, special facilities are provided for the input of user identification and addresses.
No protocol conversion facilities are provided by the Gateway protocol conversion facilities (eg X29 - TS29) can be provided by calling through a third party machine (usually on SERCNET).
The addresses used have been extended to include authorisation fields, so that users can be billed for any charges they incur.
The Gateway also provides facilities for the inspection of accounts and changing of passwords. There is also a limited HELP facility.
The interface which a user sees will depend on the local equipment to which he is attached. This may be a PAD (terminal concentrator), in which case he will probably be using the X29 protocol, or a HOST (computer) in which case he might be using FTP (the file transfer protocol).
The local equipment must have some way of generating a Transport Service Called Address for the Gateway. This is a string beginning at the fifth byte of the Call User Data Field. The Call User Data field is data supplied when the call is set up. The way in which this data is supplied is dependent on the equipment being used.
The Transport Service Called Address must include an authorisation field - the format of this is described in section 4. The documentation for the local system must therefore be consulted in order to find out how to generate the Transport Service Called Address. Some examples are given in Appendix 2.
A facility is provided for users of the X29 terminal protocol, whereby the Transport Service Called Address can be supplied interactively to the Gateway, without having to set up a Call User Data Field. In order to make use of this facility, the Gateway must be called with the correct X25 subaddress. This means adding an extra 2 digits on to the normal 12 digit address of the Gateway. See section 4.1.1.
Unauthorised use is permitted provided that no charges are incurred at the Gateway. This means normal charge incoming calls and reverse charge outgoing calls from SERCNET.
There is an account DEMO (password will be supplied on request) with a small allocation which is available for users to try out the Gateway, but it should be noted that excessive use of this account will soon exhaust the allocation, thus depriving others of its use.
Prospective users of the Gateway should first contact User Support Group the Computing Division of the Rutherford Appleton Laboratory.
4.1 To connect a call through the Gateway, the following information is required in the Transport Service Called Address:
The format of the Transport Service Called Address is as follows:
<netname(<authorisation>).<host address>
For X29 terminal calls only, an alternative format using a sub-address is available, see section 7.
4.1.1 <Netname> is one of the following:
SERCNET to connect to the SERC network PSS to connect to PSS S an alias for SERCNET
An alternative method of specifying the network to be called, using a subaddress with X29 terminal calls, is described in section 7.
4.1.2 <Authorisation> is a list of positional or keyword parameters or booleans. It is only required if charges are to be incurred at the Gateway.
Keyword Meaning US User identifier PW User's password AC the account - not used at present - taken to be the same as US RP 'reply paid' request (see section 6) R reverse charging indicator (boolean)
Keywords are separated from their values by '='. Keyword-value pairs, positional parameters and booleans are separated from each other by ','. A boolean is a value which is either true or false, depending on the presence or absence of the keyword. The whole string is enclosed in parentheses: ().
Examples:
(FRED,XYZ,R) (US=FRED,PW=XYZ,R) (R,PW=XYZ,US=FRED)
All the above have exactly the same meaning. The first form is the most usual.
When using positionals, the order is: US,PW,AC,RP,R
4.1.3 <Host address> is the address of the machine being called on the target network. It will normally consist of the numeric address of the machine being called and a service name indicating which protocol on that machine is to be used. The numeric address is separated from the service name by a point (.).
The numeric address may be replaced by an alphanumeric mnemonic string, if one has been set up on the Gateway. A list of these is given in Appendices 1A and 1B. The service name may be absent, for some protocols, for example X29 terminal calls.
Examples:
RLGB.FTP 2105.FTP
Both the above would refer to the FTP service on the GEC 'B' machine at Rutherford.
RLGB alone would in fact connect to the X29 server, since no service name is required for X29.
In order to connect to some machines, it may be necessary to supply an X25 subaddress. These are extra digits added on to the address for the machine.
In order to enable subaddresses to be entered more easily with PSS addresses, the delimiter '-' can be used to delimit a mnemonic address. When the mnemonic is translated to an address the delimiting '-' is deleted so that the following string is combined with the address. Eg:
SERC-99 is translated to 23422351919199
4.2 The full address
Putting the above mentioned three components together a full Transport Service Called Address might look like this:
S(FRED,XYZ,R).RLGB.FTP
Of course a request for reverse charging on SERCNET is meaningless, but not illegal.
Certain special services are available on an 'auto-connect' basis. These services are accessed by making an X29 terminal call to the Gateway on subaddress 64 or 66. This means that the full addresses to use when calling from PSS are:
23422351919164 Telex distribution service (for RAL) on SERCNET 23422351919166 Poste-Restante enquiry service on SERCNET
No other information is required other than the subaddress in order to effect a connection (when calling from PSS).
Further information on these services is given in section 11.
(Omit at first reading)
In many circumstances it is necessary for temporary authorisation to be passed to a third party. For example, the recipient of network MAIL may not himself be authorised to use the Gateway, and therefore the sender may wish to grant him temporary authorisation in order to reply. With the Job Transfer and Manipulation protocol, there is a requirement to return output documents from jobs which have been executed on a remote site.
The reply paid facility is invoked by including the RP keyword in the authorisation. It can be used either as a boolean or as a keyword-value pair. When used as a boolean, a default value of 1 is assumed.
The value of the RP parameter indicates the number of reply paid calls which are to be authorised. All calls which use the reply paid authorisation will be charged to the account of the user who initiated the reply paid authorisation.
The reply paid authorisation parameters are transmitted to the destination address of a call as a temporary user name and password in the Transport Service Calling Address. This is a string in the Call User Data Field similar to the Transport Service Called Address, but indicating where the call has come from. The temporary user name and password are in a form available for use by automatic systems in setting up a reply to the address which initiated the original call.
Each time a successful call is completed using the temporary user name and password, the number of reply paid authorisations is reduced by 1, until there are none left, when no further replies are allowed. In addition there is an expiry date of 1 week, after which the authorisations are cancelled.
In the event of call failures and error situations, it is important that the effects are clearly defined. In the following definitions, the term fail is used to refer to any call which terminates with either a non-zero clearing cause or diagnostic code or both, regardless of whether data has been communicated or not. The rules are defined as follows:
There is a problem in that X29 is incompatible with the Yellow Book Transport Service. For this reason, it is possible that some PAD implementations will be unable to generate the Transport Service Called Address. Also some PAD's, eg the British Telecom PAD, may be unable to generate a Call User Data Field longer than 12 characters - insufficient to hold the Transport Service Address.
If the PAD is able to generate a Call User Data Field, then the text entered at the terminal will normally begin at byte 5. The first character is treated as a delimiter, and should be entered as the character @. This is followed by the Transport Service Called Address, described in section 4.
Alternatively, the network name can be specified as an X25 subaddress, 69 for SERCNET, and 96 for PSS. The Gateway will then prompt for the rest of the Transport Service Called Address. The procedure is as follows:
First call the Gateway with the correct subaddress:
23422351919169 to call SERCNET from PSS 00000000004096 to call PSS from SERCNET
The response from the Gateway will be the following message:
Please enter your authorisation and address required in form: (user,password).address >
Reply with the appropriate response eg:
(FRED,XYZ).RLGB
In some cases authorisation is not required, in which case the (FRED,XYZ) string can be omitted. Note that the address should still be preceded with a point (.). In particular authorisation is not required when no charges are incurred at the Gateway, ie for normal charge incoming calls and reverse charge outgoing calls.
There is a timeout of between 3 and 4 minutes for this response, after which the call will be cleared. There is no limit to the number of attempts which may be made within this time limit - if the authorisation or address entered is invalid, the Gateway will request it again. To abandon the attempt, the call should be cleared from the local PAD.
Due to the lack of a Transport Service ACCEPT primitive in X29, it will be found, on some PADs, that a call connected message will appear on the terminal as soon as the call has been connected to the Gateway. The call connected message should not be taken to imply that contact has been made with the ultimate destination. The Gateway will output a message Call connected to remote address when the connection has been established.
This is the ideal protocol to use through the Gateway, since there should be no problem about entering the Transport Service address. However, it is advisable first to ascertain that the machine to be called will support TS29.
When using this protocol, the service name of the TS29 server should be entered explicitly, eg:
S(FRED,XYZ).RLGB.TS29
Due to the present lack of a full Transport Service in the Gateway, some primitives are not fully supported.
In particular, the ADDRESS, DISCONNECT and RESET primitives are not fully supported. However this should not present serious problems, since the ADDRESS and RESET primitives are not widely used, and the DISCONNECT primitive can be carried in a Clear Request packet.
The Gateway does not support continuation of Transport Service Connect messages into the first data packet. This may cause some problems, particularly when attempting file transfers from sites which do not support Fast Select (ie more than 12 characters in the Call User Data Field).
Access to IPSS, the international packet network, is through PSS. The IPSS address should be entered in place of the PSS address. IPSS calls are accounted separately from PSS and therefore an IPSS allocation must be specifically requested if calls are to be made to IPSS.
Access is also available to the Telex network from SERCNET. The address used should be the Telex number of the terminal to be called, preceded by 2348. A mnemonic address of TELEX is available, which translates to 2348, so that the form TELEX-<te1ex number> can be used. TELEX calls are accounted separately from PSS and IPSS calls and therefore a Telex allocation must be specifically requested if this service is required.
Only inland Telex calls can be made at the present time.
Two special services are available for incoming calls from PSS. These are available on auto-connect, and are accessed by calling the following addresses:
23422351919164 Telex distribution service 23422351919166 Poste-Restante service
Although this service is provided primarily to support incoming Telex, it can also be used by any incoming X29 call, to distribute MAIL. To access it from the Telex network, the Telex terminal must first connect to Interstream one (British Telecom's gateway between Telex and PSS), on 20083. Interstream one will respond with KEY+. The address 23422351919164 should then be entered.
Having connected to the Telex Distribution service, the following procedure should be used to enter a message into the MAIL system:
Begin the message with
TO: <name of recipient>
<name of recipient> should preferably be entered in the form initials plus surname.
Now enter the body of the message, followed by the name of the sender.
Clear the call when finished.
The same procedure can be adopted by PSS users of this service, when making an X29 terminal call.
This service enables users of the Telex Insertion service to obtain replies. When the recipient of MAIL delivered by the Telex Insertion system replies, his reply will be stored by the Poste Restante service. Now when the sender of the original MAIL connects to the Poste Restante service, the reply will be printed on his terminal.
This service may be accessed either from Telex, by calling 20083 KEY+23422351919166, or from PSS.
Some hosts on PSS (or more likely IPSS) are unable to accept Fast Select calls. This is a facility, which may be subscribed to by a PSS user, which allows calls to have up to 128 bytes in the Call User Data Field.
If a Fast Select call is made to an address which does not subscribe to the Fast Select facility, the call will fail.
When a mnemonic is used, the Gateway will know whether the address can support Fast Select or not, and will make the correct call automatically. If the full numeric address is used, then it will be necessary to tell the Gateway not to use Fast Select. This can be done by preceding the address with the string NFS-.
In fact the NFS is a mnemonic which translates to a null string with the no Fast Select attribute, and the minus is a self destructive delimiter. For example, calling TELENET:
PSS(FRED,XYZ).NFS-311012345678
Some networks (for example TYMNET) require a Call User Data Field with a different format from the transport service one normally generated by the Gateway. A facility has been provided to enable an arbitrary string to be included in the Call User Data Field beginning at the fifth byte.
This is done by terminating the numeric address (or mnemonic) with the delimiter *D followed by the required string. Everything following the *D is then copied into the Call User Data Field beginning at byte 5.
Example:
PSS(FRED,XYZ).NFS-31060000*DZRRT;IPSSLON
This would call a (fictitious) address on TYMNET.
A PSS Gateway account may be inspected or a password changed by making a call to the PSS Gateway and using the Account facility. A terminal call (X29 or TS29) is first made to the Gateway (not through it). With TS29 this is done by having a Transport Service Called Address of TS29. With X29 the Call User Data Field is left empty, and the Gateway is called without a subaddress (ie on 234223519191 from PSS or 40 from SERCNET).
A title message will then appear announcing the Gateway, followed by the lines:
Logging in User
If it does not, type <carriage return> until it does. Then type:
ACNT
After a short delay, there will be a prompt for a Userid, and when this has been entered, a Password is requested (this will not be echoed). Three attempts are allowed to enter the correct password.
The message Enter command will now appear. Commands may be abbreviated to a minimum of 2 characters. The following commands are available:
A HELP facility is available which contains the whole of this guide, in its most up to date form. The viewing utility used to access this allows context searches for strings as well as random movement about the document.
There is also additional up to the minute information, and details of forthcoming changes. It is advisable to check the HELP system from time to time to find out about changes which may affect your access.
To connect to the HELP system, simply make a terminal call to the Gateway as described in section 14 above, and type HELP when the Logging in/User prompt appears.
The numeric address of the Gateway on SERCNET is 40, and on PSS it is 234223519191.
On SERCNET, the mnemonic used to make calls through the Gateway to PSS is PSS, which translates to 40.PSS. The mnemonic used to make calls to the Gateway is RLXA which translates to 40.
Accounts are maintained under 4 separate categories:
PSS full rate: PSS (FULL) PSS discount rate: PSS (DISC) Telex full rate: TLXN (FULL) IPSS full rate: IPSS (FULL)
In order to incur charges under any of these categories, an allocation must be requested when the account is set up. No allocation is required for calls which do not incur charges, eg calls on SERCNET, reverse charge calls to PSS, normal charge calls from PSS.
The PSS discount rate applies from 1800 to 0800 each night, all day weekends, Christmas day and New Years day. The PSS full rate applies at all other times. The IPSS full rate applies at all times for international calls.
When the allocation is exhausted for the current rate of charge for an active call, then the call will be cleared and all further calls at that rate refused.
When a call fails, there is an error code associated with the failure, which will normally be displayed on the user's terminal. This code consists of two fields, the first is the Clearing Cause, and the second the Diagnostic Code.
A list of the most common codes is given in Appendix 3. Further interpretation of the codes and an assessment of where an error occurred is a matter for the expert. However, the following information may be of some use in fault diagnosis.
When a call is cleared or fails to set up correctly, a Clear Request packet passes through the Gateway. If it is a host generated clear, then the Clearing Cause is a and the Diagnostic Code is assumed to be a Transport Service error code, in which case, the code is passed through the Gateway transparently.
If it is a network generated clear, then the Clearing Cause is non zero, and the Gateway will map the Clearing Cause/Diagnostic Code on to a zero Clearing Cause and a Transport Service Diagnostic Code inevitably some information is lost in this process.
Thus if a non zero Clearing Cause appears in a message, then the call was cleared by the network nearest to you, and the Clear Request packet has not passed through the Gateway.
For X29 calls, when a call is cleared, a GEC style text call cleared message is generated by the Gateway. This contains two 2 byte error codes. The first is a 2 byte GEC Data Management error code and the second 2 bytes are the Clearing Cause and Diagnostic Code. In this case the Clearing Cause and Diagnostic Code are not translated.
| Address | Mnemonic | Establishment |
|---|---|---|
| 2062221006 | BBDA | Brussels DEC A (Belgium) |
| 208034020258 | CNUSC | CNUSC Montpelier |
| 20807802016901 | INRIA | Institute Nucleare Reserche. |
| 208091000309*DCISIFMST | CISI | IBM (TSO) |
| 208091000309*DCISIFMST | CISI1 | IBM (TSO) |
| 208091000519*DCISIFMST | CISI2 | IBM - TSO |
| 208091000270*DCISIFMST | CISI3 | IBM - TSO |
| 208091010320 | CJRCE | |
| 208091040047 | SACLAY | Saclay - France |
| 2223077*DQUESTD5 | ESA | ESA |
| 2223078*DQUESTD5 | ESA2 | ESA |
| 2283101*DN | DATASTAR | Data-Star, Switzerland |
| 22846811405 | CERN | CERN |
| 2284681140510*DLO | CERNLO | CERN 300 bps |
| 2284681140510*DME | CERNME | CERN 1200 bps |
| 234212300120 | DIALNET | IGS Leased line to DIALOG in US |
| 234219200118 | ADPUK | ADP Network Services Ltd |
| 234219200146 | CEGB | CEGB, Park Street, London |
| 234219200190 | NFOLINE | Pergamon - Infoline |
| 234247302022 | MHGA | LDC at Martlesham |
| 234219200203 | IPSH | IP-SHARP |
| 234219200222 | BLAISE | British Library Information System |
| 234219200300 | UCL | University College London - Computer Science |
| 234219200333 | EUCLID | University College London - Computer Centre |
| 234219201002 | POOLE | |
| 234219201005 | PSSMAIL | PSS TELE-MAIL service |
| 23421920100515 | TINS | BT on line TINS |
| 23421920100615 | PSSDOC | PSS documentation service |
| 23421920101013 | HOSTESS | Hostess system (BT) |
| 23421920101013 | TSTA | Hostess system (BT) |
| 23421920101030 | TSTB | British Telecom |
| 234219511311 | GECB | GEC Computers Ltd. Borehamwood |
| 234219709111 | NPL1 | National Physical Laboratory |
| 234219709210 | NPL2 | National Physical Laboratory |
| 234219806160 | QMC | Queen Mary College London |
| 234220641141 | ESSX | University of Essex |
| 234221222122 | MIDB | MIDNET Gateway at Birmingham |
| 234221222122 | BLEND | as above (Birmingham/Loughborough Electronic Network) |
| 234221222223 | BIRP | Prime R & D at Birmingham |
| 23422223616300 | CARDF | University of Cardiff |
| 234222236163 | CARDF | University of Cardiff |
| 234222236236 | UWIST | University of Wales |
| 234222339399 | CAMB | University of Cambridge |
| 234222530303 | SWURCC | South-West Universities |
| 234222715151 | KENT | University of Kent |
| 234223440144 | BED5 | Prime R & D at Bedford |
| 234223440345 | TI | Texas Instruments Ltd |
| 234223519111 | AERE | Atomic Energy Research Establishment at Harwell |
| 23422351911198 | ADA | ADA UK Database |
| 234223519191 | SERC | Gateway to SERCNET at Rutherford |
| 234227230230 | BRST | University of Bristol |
| 23422723033300 | AUCC | Avon Universities Computer Centre |
| 234227230333 | AUCC | Avon Universities Computer Centre |
| 23423135435422 | ERCC | Edinburgh Regional Computer Centre |
| 234233458158 | STAN | University of St. Andrews |
| 23423923232304 | EXTR | University of Exeter |
| 234241260106 | SCRSX | Strathclyde 11/40 RSX system |
| 234241260260 | GLSG | University of Glasgow |
| 234246240240 | ICLL | ICL at Letchworth |
| 234251248248 | LIVE | University of Liverpool |
| 234253265165 | LEEDS | University of Leeds |
| 23425330012406 | CAMTEC | Camtec, Leicester (hardcopy printer) |
| 234253300124 | CAMTEC | Camtec, Leicester |
| 234258200106 | ARC | Agricultural Research Council (GEC Switch) |
| 234258240242 | GECD | GEC Computers Ltd at Dunstable |
| 234260227227 | MIDN | MIDNET Gateway at Nottingham |
| 234261643143 | UMRCC | University of Manchester Regional Computer Centre |
| 234261643210 | SALF | Salford University |
| 234261643343 | FERRANTI | Ferranti Computer Systems |
| 234263259159 | NUMAC | University of Newcastle |
| 234270712217 | HATF | Hatfield Polytechnic |
| 234273417317 | DECR | DEC at Reading |
| 234273417217 | MODC | Modcomp |
| 234275317177 | GSI | OSI |
| 234290468168 | YORK | Gateway to DEC-10 at York |
| 234290524242 | RSRE | Radio, Space Research Establishment |
| 234292549149 | DL | SERC at Daresbury Laboratory |
| 234293212212 | BOC | British Oxygen Company |
| 234293212212 | DATASOLVE | as above |
| 234299212221 | NLTN | Nolton |
| 234307813 | EUROINFO | Euronet Diane Information Service |
| 2405015310 | QZDB | QZ ODEN DEC-10 |
| 2405015320 | QZCB | QZ Cyber |
| 2405015330 | QZIB | QZ Amdahl |
| 24050154 | UPPS | Uppsala network, Sweden |
| 24050253 | QZXB | QZ by yet another route |
| 2405020328 | QZXA | QZ Sweden via reverse PAD |
| 2405020332 | QZDA | QZ DEC 10 Sweden |
| 2405020332 | QZ | QZ DEC 10 Sweden |
| 242211000001*D03 | OSLO | DEC10 at Oslo University |
| 242223000001*DOO | RBK | Cyber 170 at IFE, Kjeller |
| 242245000001*DOO | BERGEN | Univac at Bergen University |
| 242253000001*D11 | RUNIT | Univac at Trondheim University |
| 242265000001*D81 | TROMSOE | LAN at Tromso University |
| 262453000217 | HMI | HMI in Berlin |
| 2624540008001 | DYVA | MARK J VAX at DESY |
| 2703035 | EUROSTAT | ICL2982 EEC Eurostat system in Luxembourg |
| 302067200040 | UBCVCR | Amdahl, Univ British Columbia, Vancouver |
| 3106*DENSCL | ONTYME | ONTYME information system |
| 31060061*DSDDC;IPSSLON | ORBIT2 | SDC Search Service |
| 3106900803*D | DIALOG3 | Lockheed DIALOG service |
| 3106900061*D | DIALOG4 | Lockheed DIALOG service |
| 310600266400*D | SLAC | SLAC via TYMNET |
| 31102020010900 | CIS | Chemical Information Systems |
| 311020200141 | TELEMAIL | US Telemail facility |
| 31102020014175 | TELEMAIL1 | US Telemail facility |
| 311021200141 | JPLM1 | Jet Propulsion Laboratory mail 1, USA |
| 311021200142 | JPLM2 | Jet Propulsion Laboratory mail 2, USA |
| 31102130003300*D | ORBIT | SDC Search Service |
| 31102130017000*D | DIALOG2 | Lockheed DIALOG service |
| 31102130021908 | CALTECH | Caltech VAX 11/780 |
| 31102130021909 | CALTECH2 | Caltech VAX 11/780 |
| 311031268801 | ADPUSA | ADP Network Services Ltd. |
| 31104150002000*D | DIALOG | Lockheed DIALOG service |
| 31104150004800*D | DIALOG1 | Lockheed DIALOG service |
| 31106070002000 | CORNELL0 | Cornell University |
| 31106070002100 | CORNELL1 | Cornell University |
| 31106070002200 | CORNELL2 | Cornell University |
| 31106070002200 | CORNELL | Cornell University |
| 31106070002300 | CORNELL3 | Cornell University |
| 3110808000101146 | UKIRT | UK Infra Red Telescope in Hawaii |
| 505273720000 | UQXA | University of Queensland ANF-10 gateway |
| Address | Mnemonic | Establishment |
|---|---|---|
| 204 | NL | Netherlands |
| 206 | B | Belgium |
| 2080 | TRANSPAC | French Transpac |
| 208 | F | France |
| 2141 | SPAIN | Spanish data network |
| 214 | E | Spain |
| 222 | I | Italy |
| 228 | CH | Switzerland |
| 232 | A | Austria |
| 2341 | IPSS | IPSS UK network |
| 2348 | TELEX | UK Telex network |
| 234 | GB | United Kingdom |
| 238 | DK | Denmark |
| 2405 | SWEDEN | Swedish data network |
| 240 | S | Sweden |
| 2422 | NORWAY | Norwegian data network |
| 242 | N | Norway |
| 244 | SF | Finland |
| 2624 | GERMANY | German data network |
| 262 | D | Germany |
| 268 | P | Portugal |
| 270 | L | Luxembourg |
| 272 | IRL | Ireland |
| 3020 | DATAPAC | Canadian Datapac |
| 3025 | GLOBEDAT | Canadian Globedat |
| 3029 | INFOSWITCH | CanadianInfoswitch |
| 302 | CDN | Canada |
| 3103 | ITT | USA - ITT |
| 3104 | WUI | USA - WUI |
| 3106 | TYMNET | USA - Tymnet |
| 3110 | TELENET | USA - Telenet |
| 3113 | RCA | USA - RCA |
| 3126 | AUTO | NET USA - Autonet |
| 340 | FA | French Antilles |
| 342 | BDS | Barbados |
| 425 | IL | Israel |
| 4408 | VENUSP | Japanese data network |
| 440 | J | Japan |
| 454 | HK | Hong Kong |
| 505 | AUS | Australia |
| 525 | SGP | Singapore |
| 530 | NZ | New Zealand |
| 431 | DXB | United Arab Emirates - Dubai |
| 426 | BRN | Bahrain |
| 655 | ZA | South Africa |
| NFS | No Fast Select dummy |
| Address | Mnemonic | Establishment |
|---|---|---|
| 1.ITP | ELEC | |
| 1 | RLIA | Rutherford Laboratory IBM system |
| 2 | RLIB | IBM 3081 VM/370 at Rutherford |
| 2.XXXP | RLIBP | RAL IBM Full Screen 3270 emulator |
| 5 | GWGA | GEC 4070 at Glasgow |
| 6 | RLPA | PRIME 750 at Rutherford (Prime A) |
| 14 | NMPA | PRIME 400 at Nottingham |
| 18 | ZUGA | UCL GEC 4085 E.W.S. |
| 19 | HQGA | GEC 4085 at NERC Swindon |
| 20 | RSGA | Appleton GEC 4070 |
| 22 | RLPB | PRIME 750 at Rutherford (Prime B) |
| 23 | RLPC | EBL PRIME 750 at Rutherford (Prime C) |
| 25 | WKPA | PRIME 550 at Warwick |
| 26 | SYPE | PRIME 550 at Surrey |
| 27 | SVPA | PRIME 550 at Sussex |
| 28 | UMPA | PRIME 750 at UMIST |
| 32 | ZUXA | UCL LSI11 Gateway |
| 33 | RLVS | Starlink VAX 11/780 at Rutherford |
| 35 | XXWA | Nuc. Phys. GEC 2050 Workstation at Oxford |
| 36 | XXVA | HEP VAX 11/780 at Oxford |
| 37 | RLGK | GEC 4090 at Rutherford |
| 38 | XXWB | DL GEC 4065 Graphics Workstation, Oxford (Zoology) |
| 40.PSS | PSS | |
| 40 | RLXA | RL GEC 4065 PSS Gateway |
| 46 | ZMGA | GEC 4070 at Queen Mary College |
| 48 | ZIVA | HEP VAX at Imperial |
| 51 | RLWB | GEC 2050 (Remote 19) at Rutherford |
| 53 | RLWA | Development GEC 2050 at Rutherford |
| 57 | ZIWA | GEC 2050 at Imperial College London |
| 58 | RLVA | HEP VAX 11/780 at Rutherford |
| 59 | RHWA | GEC 2050 at Royal Holloway College |
| 65 | RLVB | BCRG VAX 11/780 at Rutherford |
| 66 | ZUXB | UCL LSI-11 TELETEX development |
| 67 | RLGM | GEC 4190 - RAL Mail Machine |
| 68 | GWIA | IBM 4341 at Glasgow |
| 69 | RLVC | RAL VAX 11/750 St/CB in R26 |
| 1100 | RLCA | RL PAD ATLAS 01 |
| 1101 | RLCB | RL PAD ATLAS 02 |
| 1102 | RLCC | RL PAD in R25 |
| 1103 | RLCD | RL PAD in R2 |
| 1104 | RLCE | RL PAD in R1 (tel exch) |
| 1105 | RLCF | RL PAD in R1 (1.75) |
| 1106 | RLCG | RL PAD ATLAS 03 |
| 1107 | RLCH | RL PAD (spare) |
| 1108 | RLCI | RL CAMTEC pad |
| 00000000110801 | RLCIP | RL CAMTEC pad |
| 1109 | RLCJ | RL CAMTEC pad |
| 2100 | RLPD | PRIME 400 at Rutherford (Prime D) |
| 2101 | RLPF | Prime 750 - Technology Division |
| 2102 | RLPE | Prime 550-I1 - Lab overheads. |
| 2103 | RLGF | GEC 4065 in R3 |
| 2104 | RLPG | Ral Tech Division Prime |
| 2105 | RLGB | GEC 4090 - RLGB at Rutherford |
| 2105.XXX.STATUS | STATUS | Status Polling process at RAL |
| 2201 | XXDA | Oxford HEP DEC 10 |
| 2202 | RLXC | Reverse Pad at RAL |
| 2300 | CFGA | GEC 4090 at Cardiff |
| 2301 | BRGA | GEC 4090 at Bristol |
| 2302 | BHGA | GEC 4080 At Birmingham |
| 2303 | RGGA | GEC 4070 at Reading |
| 2304 | SNGA | GEC 4070 at Southampton |
| 2306 | CDGA | GEC 4085 at Cranfield |
| 2307 | LTGA | GEC 4090 at Leicester Poly |
| 2308 | DYGA | GEC 4160 at DESY,· Hamburg |
| 2309 | PHGA | SERC GEC 4160 at Polaris House |
| 2400#00 | EXXA | GEC TS gateway at Exeter |
| 2400104 | EXXA | GEC gateway at Exeter (X29) |
| 2500 | RLGD | RL ISG 4090 |
| 2501 | RLGU | RL GEC 4065 Universe LDC |
| 2502 | LHGU | Loughborough GEC 4065 Universe LDC |
| 2503 | RLXU | Universe TS gateway to ring |
| 2504 | RLGV | Universe Exhibition LDC |
| 2505 | RLDA | RAL DCS PDP 11/70 |
| 2600 | GXVA | RGO VAX 11/750 |
| 2601 | XXVC | OXFORD COMP. CENTRE VAX |
| 2602 | GXVS | RGO STARLINK VAX 11/780 |
| 2604 | RLVD | RAL IKBS VAX 11/750 in R26 |
| 1000200*D:TSO | DLIA | |
| 1000200*D:TSO | TSO | |
| 1000200*D:NETSTAT | NETSTAT | |
| 1000200*D:ITP.1000450.046400 | TELLDL | |
| 1000200*D:ITP.1000450.04FEOO | HELPDL | |
| 1000050.465 | NETMON | |
| 1000050.44400 | LOG | |
| 1000050 | DLXA | DL Gateway to Daresbury site |
| 1000100 | DLGC | DL GEC at Daresbury (Network monitor) |
| 1000200 | DLGD | DL GEC at Daresbury (Network converter) |
| 1000300 | DLGE | DL GEC 4090 at Daresbury |
| 1000450 | DLXB | DL Site Area RJE4 |
| 1002000 | DLVA | DL SRS VAX 11/750 at Daresbury |
| 1002100 | DLGM | DL GEC 4065 MAIL machine |
| 1003000 | DLCA | JNT pad at DL |
| 1011700 | DLGA | DL CSE/1 GEC 4070 at Daresbury |
| 1011750 | NNGA | DL NSFD/R1 at Daresbury |
| 1011750 | DLGB | DL NSFD/R1 GEC 4085 at Daresbury |
| 1020050 | MAXA | DL Gateway to Manchester site |
| 1020100 | MAGB | DL GEC 4190 at Manchester |
| 1020300 | MAGA | Manchester GEC 4090 E.W.S. |
| 1030050 | LLXA | DL Gateway to Liverpool site |
| 1030100 | LLGA | DL GEC 4085 at Liverpool |
| 1030200 | LLGB | Liverpool Graphics GEC 4085 |
| 1040000 | QUXA | DL Gateway to Queens Univ. Belfast |
| 1050000 | BGXA | UCNW (Bangor) DEC-10 Gateway |
| 1060000 | BHXA | DL Gateway to Birmingham site |
| 1060100 | BHGB | DL NSF GEC 4065 at Birmingham |
| 1070000 | SHWA | DL PDP-11 workstation at Sheffield |
| 1070100 | SHGA | GEC 4085 at Sheffield |
| 1070200 | SHXA | DL Gateway to Sheffield site |
| 1080100 | BDGB | Bradford GEC 4065 |
| 1080200 | BDGA | GEC 4082 at Bradford |
| 1080500 | LEVA | VAX at Leeds University (Mech Eng) |
| 1080501 | LEVB | VAX at Leeds |
| 1090000 | GWXA | DL Gateway to Glasgow site |
| 1100200 | WKWA | DL PDP-11 workstation at Warwick |
| 1101100 | LAVA | Lancaster University HEP VAX |
| 1101200 | LAWA | DL PDP-11 workstation at Lancaster |
| 1102000 | KECA | Keele University CAMTEC PAD |
| 1500100 | NEDA | Newcastle DCS-UNIX front-end |
| 1500200 | NEVA | Newcastle VAX 11/780 |
| 1500300 | NEGA | GEC 4070 at Newcastle |
| 1501000 | DUGA | GEC 4080 at Durham |
| 1502000 | DUVS | Durham Starlink VAX |
| 1600100 | SDPA | PRIME 750 at Salford |
| 2002100 | ZKGA | GEC 4065 at Kings college, London |
| 2003000 | ZAWA | PDP-11/70 at Birkbeck college |
| 2005002 | ZUVS | Starlink VAX at UCL |
| 2005003 | ZUPA | PRIME 550 at UCL |
| 2005004 | ZUGU | GEC 4065 Universe LDC at UCL |
| 2005100 | ZUXC | UCL CS LSI 11 |
| 2005200 | ZUXU | UCL Universe T/S Gateway |
| 2006001 | ZIGA | GEC 4065 at Imperial College, London |
| 2007001 | CYPA | PRIME 550 at City University |
| 2008001 | ZWGA | GEC 4085 at Westfield College, London |
| 2009001 | ZMVA | QMC Physics VAX |
| 2010001 | KTDA | PDP 11/34 gateway at Kent |
| 3001000 | BIXA | Bidston Sub-switch 1 |
| 3002000 | BIXB | Bidston Sub-switch 2 |
| 3003000 | BIHT | Bidston Honeywell test |
| 3006000 | GEXA | GEC Exchange at NERC Edinburgh |
| 5000000 | LNXA | Gateway to the London area |
| 6000000.ITP | BALHAM | |
| 6000000 | YKXA | DECNET Gateway at York (BALHAM) |
| 6000001 | YKDA | DCS PDP 11/44 (Unix) at York |
| 6000003 | YKDB | Unix VAX at York |
| 7001001.XXX | GRETNA | |
| 7001001 | EDXA | DECNET Gateway at Edinburgh (GRETNA) |
| 7001002 | EDXB | RCONET Gateway at Edinburgh |
| 7001003 | EDXC | Second Gretna |
| 7001004 | EDXD | ERCC CPSE |
| 7001005 | EDQA | ERCC PERQ |
| 7001010 | EDCA | ERCC PAD |
| 7001100 | EDGA | NSF GEC 4065, Physics, Edinburgh |
| 7001200 | EDGB | GEC 4060 Workstation, Physics, Edinburgh |
| 7001301 | IDQA | ICL PERQ at Dalkeith |
| 7001302 | IDQB | ICL PERQ at Dalkeith |
| 7001303 | IDQC | ICL PERQ at Dalkeith |
| 7002001 | REGA | GEC 4090 at ROE |
| 7002002 | REVS | Starlink VAX at ROE |
| 7003001 | HWGA | GEC 4070 at Heriot Watt University |
| 7004001 | EKVA | East Kilbride Kelvin Lab VAX |
| 7006001 | DDXA | DECnet Gateway at Dundee |
| 7007001 | SAVA | ST. Andrews VAX |
| 7008001 | SGVA | Stirling University VAX |
| 7009001 | ABXA | Aberdeen CPSE |
| 7010001 | SRXA | Strathclyde CPSE |
| 8001001 | CAGA | GEC 4090 at Cambridge |
| 8002010 | CAGU | Universe GEC 4065 at Cambridge |
| 8002011 | CAXU | Cambridge Univ T/S gateway |
| 8002020 | CAXA | Gateway to Cambridge University |
| 8003001 | CAVA | HEP VAX at Cambridge |
| 8004001 | GRGU | Universe GEC 4065 at Great Baddow |
| 8004002 | GRXU | CPSE gateway and support system |
| 8005001 | CAVS | Starlink VAX at Cambridge |
| 8006001 | EAPA | PRIME 400 at East Anglia |
| 8006002 | EAVA | East Anglia (Stocker) VAX |
| 9001001 | CPXA | Cernnet Gateway |
| 9001002 | CPGA | GEC 4160 at CERN |
| 9001003 | CPXB | CERN reverse PAD (Test) |
| 9001004 | CPVB | CERN Hyperon VAX |
| 9002001 | CPVA | CERN Development VAX |
| 9002002 | CPVC | CERN Omega VAX |
| 9002003 | CPVD | CERN Merlin VAX |
| 10000001 | MRXA | CPSE at UMRCC |
| 10100001 | MAVG | VAX 11/750 at Manchester CGU |
| 11000001 | QUXA | CPSE at Queens, Belfast |
A mnemonic PSS exists which translates to 40.PS5, so the procedure is as follows (user input is underlined):
Type <CR> until the terminal speed is recognised and the login prompt obtained.
<System Title> Logging in User !!PSS(<authorisation>).<mnemonic><CR> 054000 XXX version 8 Calling ... Call connected
Call connected to remote address. If the call is successful, there may now be a title message printed by the target system, dialogue follows, then to terminate the call:
@Q<CR> Call cleared <statistics message>
<CR><CR><CR><CR> OS4000 R4.0 V02 ATLAS Logging in user !!PSS(FRED,XYZ).SWRC<CR> OS4000 XXX version 8 Calling ... Call connected Call connected to remote address Welcome to SWUCN ?// LOGIN @Q<CR> Call cleared Data 11 segments, elapse 6 seconds.
The called network name may be typed into the Call User Data Field. This is limited to 12 characters because the Fast Select facility is not available.
Alternatively the called network name may be included as an X25 subaddress, as in the example below.
Having dialed up the PAD, it is first necessary to type several <CR> characters to indicate the terminal speed - no indication is given of when this is recognised - then continue:
V5<CR> _<PAD title message> N<NUI>-A22351919169 23422351919169+COM Please enter your authorisation and address required in form: (user,password).address >(<authorisation>>).<mnemonic><CR> Call connected to remote address
If the call is successful, there may now be a title message printed by the target system. (Dialogue follows) To terminate the call:
<CTRL P>CLR<CR> <PAD clear confirmation message>
If a hardcopy terminal is being used, it will probably be necessary to set PAD parameter 14 to about 5 to avoid losing characters at the start of a line. This is done by typing <CTRL P>SET14:5<CR>
<CR><CR><CR><CR><CR><CR><CR><CR><CR>V5<CR> RDG/A01-73417400 NUSERID123456-A22351919169 23422351919169+COM Please enter your authorisation and address required in form: (user,password).address > (FRED,XYZ).RLGB<CR> Call connected to remote address OS4000 R4.0 V02 ATLAS Logging in user <CTRL P>CLR<CR> CLR CONF (00) 00:00:00:21 287 113
Networked GEC 2050 workstations on SERCNET support only ITP. It is therefore necessary first to make a call to a machine which supports both ITP and X29 in order to convert, such as RLGB:
<Time>: COMMUNICATION ESTABLISHED !!RLGB<CR> <Time>: !!RLGB - OK CALLING RLGBI <Time>: CALL CONNECTED 034000 R4.0 V02 ATLAS Logging in user !!!PSS(<authorisation>).<mnemonic><CR> OS4000 XXX version 8 Calling ... Call connected Call connected to remote address
If the call is successful, there may now be a title message printed by the target system. Dialogue follows. To terminate the call:
@Q<CR> <Time>: TERMINAL CALL CLOSED:
14.56: COMMUNICATION ESTABLISHED !! RLGB<CR> 14.56: !!RLGB - OK CALLING RLGBI 14.56: CALL CONNECTED OS4000 R4.0 V02 ATLAS Logging in user !!!PSS(FRED,XYZ).SWRC<CR> OS4000 XXX version 8 Calling ... Call connected Call connected to remote address Welcome to SWUCN ?// LOGIN @Q<CR> 14.59: TERMINAL CALL CLOSED:
A mnemonic PSS exists which translates to 40.PSS, but the authorisation and address must be entered in response to the Gateway request.
Type <CR> until the terminal speed is recognised and the PAD prompt obtained.
PAD n line n speed nnnn PAD>call pss<CR> Please enter your authorisation and address in form: (user,password).address . > (<authorisation>).<mnemonic><CR> Call connected to remote address
If the call is successful, there may now be a title message printed by the target system. Dialogue follows. To terminate the call:
<BREAK> PAD>clear *** Cleared
<CR> PAD 3 line 7 speed 9600 PAD>call pss<CR> Please enter your authorisation and address in form: (user,password).address > (FRED,XYZ).SWRC<CR> Call connected to remote address Welcome to SWUCN ?// LOGIN <BREAK> PAD>CLEAR *** Cleared
Call clear request packets have two 8 bit fields used for error codes. These are called the Clearing Cause and Diagnostic codes. Network errors fall into 2 classes: those generated by the network which have a non-zero clearing cause, and those generated by hosts (DTE's) which have a zero clearing cause. In either case, the diagnostic code may be non-zero, but will have a different interpretation in the 2 cases.
There are a large number of diagnostic codes which may be set in addition to the clearing causes, however the clearing cause will usually provide sufficient information, and the diagnostic code does not alter the meaning of the clearing cause.
All codes are in hexadecimal.
| Clearing Cause |
Diagnostic Code |
Meaning |
|---|---|---|
| 00 | ** | DTE Clearing |
| 01 | ** | Number Busy |
| 03 | ** | Invalid Facility Request |
| 05 | ** | Network Congestion |
| 09 | ** | Out of Order |
| 0B | ** | Access Barred |
| 0D | ** | Not Obtainable |
| 11 | ** | Remote Procedure Error |
| 13 | ** | Local Procedure Error |
| 19 | ** | Reverse Charging not subscribed |
| 21 | ** | DTE Incompatible Call |
All Host generated clear requests have the clearing cause set to zero. The diagnostic code contains a Transport Service error code as follows (all in hexadecimal) :
| Clearing Cause |
Diagnostic Code |
Meaning |
|---|---|---|
| 00 | 00 | Successful completion of call |
| 00 | 01 | Disconnect in response to received DISCONNECT |
| 00 | 10 | No connection (unspecific) |
| 00 | 11 | Number busy |
| 00 | 12 | Out of order |
| 00 | 13 | Invalid address |
| 00 | 14 | Access barred |
| 00 | 15 | Incompatible facilities (Quality of Service) |
| 00 | 16 | No reverse charging |
| 00 | 17 | Network congestion |
| 00 | 18 | Message too long |
| 00 | 20 | Protocol error (Apology - from source of error) |
| 00 | 21 | Protocol error (Accusation - to source of error) |
| 00 | 22 | Timeout |
| 00 | 23 | No record of connection (record lost) |
| 00 | 24 | Flow control error |
| 00 | 25 | Congestion |
| 00 | 26 | Network failure |
| 00 | 27 | Application failure |
| 00 | 28 | Transport service failure |
| 00 | 29 | Call killed by operator |
| 00 | 2A | Call abandoned by transport service |
| 00 | 2B | Node going out of service |
| 00 | 2C | DISCONNECT in response to RESET |
| 00 | 2D | RESET before ACCEPT |
| 00 | C0 | Fast select required on this call |
| 00 | C1 | Invalid authorisation information |
| 00 | C2 | Account exhausted |
| 00 | C3 | Unable to set up reply paid authorisation |
The following codes will only appear in X29 calls in text messages generated by the Gateway when a call is cleared.
| Code | Meaning |
|---|---|
| 8000 | Call cleared |
| 8905 | Indicates a system error in the Gateway |
| 8906 | Indicates a system error in the Gateway |
| 8909 | Indicates a system error in the Gateway |
| 830B | Insufficient resources to set up call |
| 810C | Indicates a system error in the Gateway |
| 850F | Call time out (at call setup time) |
| 8913 | Indicates a system error in the Gateway |
| 8521 | Call Abandoned by the Gateway |
| 8927 | Indicates a system error in the Gateway |
| 8528 | Line failure - communication with network lost |
| 852B | Invalid address |
For errors 8000 and 8521 only, the diagnostic code contains further information indicating the reason for the call clearing.
