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                    Guide to using Janet !!!!!!!!!!!!!

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> THE COMPUTER BOARD AND THE RESEARCH COUNCILS
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> NETWORK EXECUTIVE
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> JANET USER NOTE 3
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> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
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>                                                                    Issued by
>                                                                    S.A. Wood
> Issue 2                                                       16 August 1988
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> ____________________________________________________________________________
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>      16 August 1988
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> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
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> 
> _________________
> TABLE OF CONTENTS
> 
> 
> 1.  Warning  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
> 
> 2.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
>     2.1  Your contacts . . . . . . . . . . . . . . . . . . . . . . . . . 1
> 
> 3.  Summary of Facilities Available Across the Network   . . . . . . . . 2
> 
> 4.  Permission to Use the Gateway  . . . . . . . . . . . . . . . . . . . 2
>     4.1  Authentication and Authorisation  . . . . . . . . . . . . . . . 2
>     4.2  Charging and Accounting . . . . . . . . . . . . . . . . . . . . 3
> 
> 5.  How to make Terminal Calls TO the Gateway  . . . . . . . . . . . . . 3
> 
> 6.  How to make Terminal Calls THROUGH the Gateway . . . . . . . . . . . 4
>     6.1  The Transport Service Called Address  . . . . . . . . . . . . . 4
>     6.2  Making Calls using TS29 Protocol  . . . . . . . . . . . . . . . 6
>     6.3  The full address  . . . . . . . . . . . . . . . . . . . . . . . 6
>     6.4  Making Calls Using X29 Protocol . . . . . . . . . . . . . . . . 6
> 
> 7.  Facilities Provided by the Gateway Machine . . . . . . . . . . . . . 7
>     7.1  HELP Facility . . . . . . . . . . . . . . . . . . . . . . . . . 7
>     7.2  Account Facility and Changing Your Password . . . . . . . . . . 8
> 
> 8.  Facilities Available THROUGH the Gateway . . . . . . . . . . . . . . 9
>     8.1  Demonstration Facility  . . . . . . . . . . . . . . . . . . . . 9
>     8.2  Address Mnemonics of Remote Hosts on Networks Connected to
>          the Gateway . . . . . . . . . . . . . . . . . . . . . . . . . . 9
> 
> 9.  Facilities Available on PSS  . . . . . . . . . . . . . . . . . . .  10
>     9.1  Fast Select . . . . . . . . . . . . . . . . . . . . . . . . .  10
>     9.2  Reverse Charge Facility . . . . . . . . . . . . . . . . . . .  10
>     9.3  Access to IPSS  . . . . . . . . . . . . . . . . . . . . . . .  10
>     9.4  Calls to Other, Non-Transport Service Networks  . . . . . . .  10
>     9.5  Adjusting Packet Sizes  . . . . . . . . . . . . . . . . . . .  11
> 
> 10. Protocols Available if Supported by Both Local and Remote
>     Host Machines  . . . . . . . . . . . . . . . . . . . . . . . . . .  11
>     10.1 Network Independent File Transfer Protocol (FTP)  . . . . . .  11
>     10.2 JNT MAIL Protocol . . . . . . . . . . . . . . . . . . . . . .  12
>     10.3 Job Transfer and Manipulation Protocol (JTMP) . . . . . . . .  12
> 
> 11. Restrictions and Errors  . . . . . . . . . . . . . . . . . . . . .  12
>     11.1 Restrictions  . . . . . . . . . . . . . . . . . . . . . . . .  12
>     11.2 Errors  . . . . . . . . . . . . . . . . . . . . . . . . . . .  12
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>      16 August 1988
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> 
> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
> 
> 
> ____________
> 1.   Warning
> 
> BETWEEN 8.00 am and 10.00 am every Tuesday, network development and  service
> work is  carried  out  on  JANET.  This means that if you make a call during
> these hours there is an increased danger of the system going down which  may
> result in loss of data.
> 
> _________________
> 2.   Introduction
> 
> The Gateway is a two-way link between the U.K.  Academic Network (JANET) and
> PSS.  At present there are two  Gateways  between  JANET  and  PSS,  one  at
> Rutherford and another at ULCC in London.
> 
> The Gateway consists of a computer which holds a communications program  and
> sits between  two  networks  (JANET  and PSS in this case).  This allows the
> user to bridge the gap between the networks and access target  computers  on
> the other  network.   It  is important to realise that there are two ways of
> communicating with the Gateway - you can make calls TO the Gateway  computer
> to access  its limited user facilities or you can make calls THROUGH it to a
> target computer on the other network.
> 
> The Gateway operates as a Transport Level Gateway  in  accordance  with  the
> 'Yellow Book'  Transport  Service.   However the present implementation does
> not have a full Transport Service and therefore, there are some  limitations
> in the service provided.  For X29 which is incompatible with the Yellow Book
> Transport Service,  special  facilities  are  provided for the input of user
> identification and addresses.
> 
> The Gateway is a protocol transparent link.  This  means  that  the  Gateway
> cannot be  used  for  protocol conversion;  to do this a third party machine
> must be used.
> 
> __________________
> 2.1  Your Contacts
> 
> If you have any problems, or if you want additional information contact  the
> JANET Network Executive.  You can reach them at the following address:-
> 
> *     By Post at  . . . . . . . Network Executive,
>                                 c/o Rutherford Appleton Laboratory,
>                                 Chilton,
>                                 Didcot,
>                                 OXON.
>                                 OX11 0QX
> 
> *     By Electronic MAIL to . . PSS Gateway Support@RL.GB
>                                 The network address for RL.GB is 000000002105
> 
> *     By Telephone on . . . . . Abingdon (O235) 446748
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> 16 August 1988                                                     Page    3
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> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
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> _______________________________________________________
> 3.   Summary of Facilities Available across the Network
> 
> The network offers a number of facilities.  These are listed below for  your
> information.
> 
> *     Facilities Provided by the Gateway Machine
> 
>       - Help Facility
> 
>       - Accounting Facility
> 
> *     Facilities Available on the Way Through the Gateway
> 
>       - Demonstration Facility
> 
>       - Addresses and Mnemonics
> 
> *     Facilities Available on PSS
> 
>       - Fast Select Facility
> 
>       - Reverse Charge Facility
> 
>       - Access to IPSS (International Packet Switch Stream)
> 
>       - Calls to Other, Non-Transport Service Networks
> 
> *     Protocols Available if Supported by Both Local and Remote Host Machine
> s
> 
>       - Network Independent File Transfer Protocol (FTP)
> 
>       - JNT MAIL Protocol
> 
>       - Job Transfer and Manipulation Protocol (JTMP)
> 
> __________________________________
> 4.   Permission to Use the Gateway
> 
> _____________________________________
> 4.1  Authentication and Authorisation
> 
> No unauthenticated use of the Gateway from JANET is  allowed  regardless  of
> whether charges  are  incurred  at the Gateway or not.  Therefore to use the
> Gateway you have to  obtain  authentication  (a  userid  and  password)  and
> authorisation (a  call  allocation)  from the JANET Network Executive.  This
> consists of:
> 
>      a. USERID
>      b. PASSWORD
>      c. USAGE ALLOCATION
> 
> Note that the authorisation for PSS and IPSS is managed separately, although
> a single USERID may have authoristation for both.
> 
> There is no restriction on access from PSS.
> 
> 
> 
> 
> 16 August 1988                                                     Page    4
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> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
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> 
> ____________________________
> 4.2  Charging and Accounting
> 
> There are 4 separate charging rates, which are:
> 
>      PSS full rate:      PSS (FULL)
>      PSS discount rate:  PSS (DISC)
>      TLXN:               Telex access via Interstream 1.
>      IPSS full rate:     IPSS (FULL)
> 
> Note that the TELEX access is expensive, as the cost  includes  the  use  of
> PSS, Interstream  1  and  TELEX.   Anyone  who is interested in TELEX access
> should first discuss it with the Network Executive.
> 
> To be able to make chargeable calls you must request a  call  allocation  to
> cover   the  charging  rates  you  want  to  use  when  you  ask  for   your
> authentication.  For calls that are free e.g.  calls within JANET or  normal
> charge calls from PSS you do not need an allocation.
> 
> The PSS discount rate applies from 1800 to 0800 each night and  all  day  on
> Sundays, Christmas Day and New Year's Day.  The PSS full rate applies at ALL
> OTHER times.   The  IPSS  full  rate  applies at ALL times for international
> calls.  For details of the international rates to various countries  consult
> Network User Note 2.
> 
> If your allocation runs out during an active call, then that  call  will  be
> cleared and all further calls at that rate will be refused.
> 
> ______________________________________________
> 5.   How to Make Terminal Calls to the Gateway
> 
> It is possible to make calls to the Gateway to access the HELP  and  ACCOUNT
> facilities.
> 
> The HELP facility contains the whole of this user guide in its most uptodate
> form.  The facility allows random scans of the  document  and  searches  for
> text within the document.
> 
> The Account facility allows the user to inspect the state of his account and
> to change the password for that account.
> 
> _____________________________________
> How to make contact with the Gateway.
> 
> If you  are  calling  the  RAL  Gateway  from  PSS  use  the   DTE   address
> 234223519191.
> 
> If you  are  calling  the  RAL  Gateway  from  JANET  use  the  DTE  address
> 000000000040.
> 
> If you are  calling  the  London  Gateway  from  PSS  use  the  DTE  address
> 234219200100.
> 
> If you are calling the  London  Gateway  from  JANET  use  the  DTE  address
> 000040000040.
> 
> Make a terminal call to the Gateway.
> 
> 
> 
> 
> 16 August 1988                                                     Page    5
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> 
> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
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> 
> A title message will appear on the terminal announcing the Gateway, followed
> by the lines:
> 
>     OS4000+Rlix V30 PSS Gateway
>     Logging in
>     user
> 
> If nothing appears, keep pressing <CARRIAGE RETURN> until the above  message
> appears.
> 
> It is now possible to log in and use the Help or  Account  facilities.   For
> details of these facilities see section 7 of this document.
> 
> ___________________________________________________
> 6.   How to Make Terminal Calls Through the Gateway
> 
> The method used to make a call through the Gateway depends on  the  type  of
> PAD being  used.   If  your PAD supports TS29 the procedure is simplified as
> this protocol allows you to make calls that can cross several  networks  via
> several Gateways.   If  your  PAD  supports  X29  then  if you wish to cross
> several Gateways you normally have to stop at each one before you  can  pass
> through it.  However a special facility is provided using the Call User Data
> Field to allow X29 calls non-stop through the JANET PSS Gateway.
> 
> Whichever protocol your PAD supports, you must have some way of generating a
> Transport Service Called Address for onward routing by the Gateway.
> 
> _________________________________________
> 6.1  The Transport Service Called Address
> 
> To make a call  through  the  Gateway  you  have  to  supply  the  following
> information in  the form of a Transport Service Called Address to your local
> PAD.
> 
>      a. Netname:         the name of the network you are calling.
>      b. Authentication:  consisting of Userid and Password in that order.
>                          This can be omitted for free calls.
>      c. Host address:    the network address of the remote host.
> 
> The format of the Transport Service Called Address is as follows:
> 
>      <Netname>(<Authentication>).<Host Address>
> 
> These are explained below.
> 
> _______
> Netname
> 
> This is one of the following:
> 
>      JANET to connect to JANET
>      PSS   to connect to PSS
>      J     an alias for JANET.
> 
> 
> 
> 
> 
> 
> 
> 
> 16 August 1988                                                     Page    6
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> 
> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
> 
> 
> ______________
> Authentication
> 
> This consists of 3 fields which must be entered in the order shown.
> 
>      a. user id,
>      b. password,
>      c. A request for the call to be reverse charged.
> 
> The last field is optional.
> 
>                                           ____
> Note that the whole authentication string must be enclosed  in  parentheses.
> 
> _______
> Example
> 
>      (FRED,XYZ,R)  Requests a reverse charge call
>      (FRED,XYZ)    Requests a chargeable call.
> 
> ____________
> Host Address
> 
> This is the numeric address of the machine being called.   However  to  make
> things easier  the  numeric  address  can  be  replaced with an alphanumeric
> mnemonic if one has been set up on the Gateway.
> 
> _______
> Example
> 
>      use RLGB instead of 000000002105 to call the Rutherford GEC 'B' machine
>      use SALF instead of 234261643210 to call Salford on PSS.
> 
> For a list of these mnemonics see JANET User Notes 5 and 6.
> 
> Host addresses can be complex and it is possible to specify several Gateways
> that you must pass through to  reach  a  specific  remote  host  and/or  the
> service required.   Note  that  a  point  (.)   must be used to separate the
> numeric addresses or mnemonics from the service names.
> 
> _______
> Example
> 
>      RLPA     - this calls the Rutherford ICF Prime on Janet.
>      RLPA.FTP - this calls FTP on the Rutherford ICF Prime on Janet.
> 
> To connect to some machines, an X25 sub-address is required, which  consists
> of a  number  of  extra digits added on to the machine address.  This can be
> easily entered on the Gateway by using the delimiter '-' at the end  of  the
> mnemonic address  and  then  typing  the  sub-address.  When the mnemonic is
> translated the delimiter is ignored and the whole address is converted  into
> a continuous string.
> 
> _______
> Example
> 
> 
> Janet-69 is translated to 23422351919169
> 
> 
> 
> 
> 
> 
> 
> 16 August 1988                                                     Page    7
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> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
> 
> 
> _____________________________________
> 6.2  Making Calls Using TS29 Protocol
> 
> TS29 is the ideal protocol to use through the Gateway, since there should be
> no problem entering the Transport Service Called  Address.   However,  first
> make sure  that  the  machine you are calling will support TS29.  When using
> this protocol for network terminal calls the service name of the TS29 server
> should be entered explicitly.
> 
> _____________________
> 6.3  The Full Address
> 
> Combining all these factors a full address might look like this.
> 
>      J(FRED,XYZ).RLGB.TS29
> 
> ____________________________________
> 6.4  Making Calls Using X29 Protocol
> 
> X29 is incompatible with the 'Yellow Book' Transport Service and  some  PADS
> are unable to generate the Transport Service Called Address.  When making an
> X29 call,  the  onward Called Address may be entered into the Call User Data
> Field of the Call.  Some PADs, e.g.  the British Telecom PAD are  unable  to
> generate a  Call  User Data Field longer than 12 characters and so there may
> not be enough space to hold all the information required.  In this  case,  a
> Call must  be  established  only  as far as the Gateway, and a dialogue held
> with the Gateway to establish the next part of the connection.
> 
> If your PAD can generate a Call User Data Field, then the first character of
> the text is treated as a delimiter, and should be entered as  the  character
> '@' followed by the onward Called address.
> 
> _______
> Example
> 
> On a CAMTEC PAD one might enter:-
> 
>      CALL 00004000004096 D=@(FRED,XYZ).SOMEWHERE
> 
> to make a call through the London Gateway to SOMEWHERE on PSS.
> 
> ________________________________________
> Overcoming Call User Data Field Problems
> 
> With X29 PADs the onward Called Address can be supplied interactively at the
> Gateway without having to set up a Call User Data field.   To  do  this  the
> Gateway must  be  called  with  the  correct X25 sub-address.  This involves
> adding an extra 2 digits onto the normal 12 digit address  of  the  Gateway.
> The sub-address  for  JANET  is  69  and  96 for PSS.  The Gateway will then
> prompt for the onward Called Address.
> 
> The procedure  is  as  follows:   Call  the  Gateway   using   the   correct
> sub-address:
> 
>      23422351919169    to call JANET from PSS via the RAL Gateway
>      00000000004096    (or the mnemonic RL.PSS) to call PSS from JANET
>                        via the RAL Gateway.
> 
>      23421920010069    to call JANET from PSS via the London Gateway
>      00004000004096    (or the mnemonic LON.PSS) to call PSS from
>                        JANET via the London Gateway.
> 
> 
> 16 August 1988                                                     Page    8
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> 
> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
> 
> 
> 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.
> 
> _______
> Example
> 
>      (FRED,XYZ).SOMEWHERE
> 
> As the X29 protocol is being used there is no need to  include  the  service
> name X29.
> 
> Authentication is not required for incoming calls to JANET.   In  this  case
> the string  (FRED,XYZ)  can be omitted, note however that the address should
> still be preceded with a point.
> 
> _______
> Example
> 
>      .RLGB
> 
> There is a timeout of between 3 and 4 minutes for this response after  which
> the call  will  be  cleared,  however  there  is  no  limit to the number of
> attempts which can made within this time limit.   If  the  authorisation  or
> adress entered is invalid the Gateway will request it again.  To abandon the
> attempt clear  the call from the PAD.  For further details of how to do this
> see Network User Note 11.
> 
> You will find that on some PADs a 'call connected' message  will  appear  on
> the terminal  as  soon  as the call has been connected to the Gateway.  This
> does not mean that you have made contact  with  your  ultimate  destination.
> When you  have  contacted  the  remote  host  the  Gateway will show a 'Call
> connected to remote address' message.
> 
> _______________________________________________
> 7.   Facilities Provided by the Gateway Machine
> 
> __________________
> 7.1  HELP Facility
> 
> A HELP Facility is available which contains the whole of this guide  in  its
> most uptodate  form.  The utility which is used to view the guide allows the
> text to be searched for strings as well as allowing  random  movement  about
> the document.
> 
> There is  also  additional  up-to-the-minute  information  and  details   of
> forthcoming changes.   Use  the  HELP  system  from time to time to find out
> about changes which may affect your access to the machine.
> 
> 
> 
> 
> 
> 
> 
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> 16 August 1988                                                     Page    9
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> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
> 
> 
> To connect to the HELP system, simply make a terminal call to the Gateway as
> described in section 5 above.  When the Logging in  /  User  prompt  appears
> type HELP.  The following message will then be displayed.
> 
>      OS4000+Rlix V30 PSS Gateway
>      Logging in
>      user HELP
>      ID last used Wednesday, 10 December 1986 06:11
>      Started - Wed 10 Dec 1986 11:15:55
>      Please enter your name and establishment.
> 
> Enter your name and establishment.  You will be then be presented  with  the
> following message.
> 
>      The following options are available:
> 
>      NOTES  GUIDE  TITILES  ERRORS  TARRIF  HELP  QUIT
> 
>      Which option do you require?
> 
> The following list describes each command briefly.
> 
> NOTES    replies to user queries and any other useful information.
> GUIDE    the complete Gateway user guide.
> TITLES   list of JANET and PSS addresses and mnemonics
> ERRORS   list of error codes that you may receive.
> TARRIF   list of the PSS and IPSS charges.
> HELP     is the HELP option.
> QUIT     exits from the session.
> 
> When you exit from the HELP facility by typing QUIT, the  following  message
> will appear.
> 
>      If you have any comments, please type them now, terminate with E
>      on a line on its own. Otherwise just type <cr>
> 
>      CPU used: 1 ieu, Elapsed: 2 mins, IO: 1583 units, Breaks: 14
>      Budgets: this period = 10.00 AUs, used = 0.010 AUs, left = 9.51 AUs
>      User HELP terminal   2 logged out  Wed 10 Dec 1986 09:20:12
> 
> The above prompt gives the user an opportunity to type  in  any  queries  or
> comments that  he has about the Gateway.  These comments are viewed daily by
> the support staff at RAL.
> 
> ________________________________________________
> 7.2  Account Facility and Changing Your Password
> 
> An account can be inspected and the password changed by using this facility.
> First make a call to the Gateway  as  described  in  section  5.   When  the
> Logging in /User prompt appears type ACNT.
> 
> After a short delay, there will be a prompt for a Userid.   Enter  your  PSS
> userid, you  will  then  be prompted for your password.  Enter your password
> (this is not echoed), three  attempts  are  allowed  to  enter  the  correct
> password.  The message 'Enter command' will now appear.
> 
> 
> 
> 
> 16 August 1988                                                     Page   10
> 
> 
> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
> 
> 
> _______
> Example
> 
>      OS4000+Rlix V30 PSS Gateway
>      Logging in
>      user ACNT
>      ID last used Wednesday, 10 December 1986 09:14
>      Enter userid FRED
>      Password
> 
>      Enter command
> 
> The following commands are available:
> 
>      ACCOUNT   Prints the state of your account on the terminal
> 
>      PASSWORD  Allows the password to be changed. The new password
>                should be typed in twice on the following two
>                lines when prompted. It is not echoed
> 
>      END       Terminates the session.
> 
> Note that each command may be abbreviated to a minimum of 2 characters.
> 
> _____________________________________________
> 8.   Facilities Available Through the Gateway
> 
> ___________________________
> 8.1  Demonstration Facility
> 
> There is an account available which has a  small  allocation  available  for
> users to try out the Gateway.  The password will be supplied on request from
> the Network  Executive.   Note  that excessive use of this account will soon
> exhaust its allocation and deprive others of its use.
> 
> ___________________________________________________
> 8.2  Address Mnemonics of Remote Hosts on Networks
>      ________________________
>      Connected to the Gateway
> 
> Many network addresses consist  of  12  or  even  14  digits  which  may  be
> difficult to remember and awkward to enter.  To make life easier the Gateway
> has a  table  which  consists  of a number of mnemonics and their respective
> network addresses.  When these mnemonics are typed within a call through the
> Gateway the mnemonic is translated into the appropriate network address.
> 
> Therefore if you have a frequently used network address which is not in  the
> table, please  contact  the  Network  Executive with a request to insert the
> address along  with  an  appropriate  mnemonic.   Equally  if  you  know  of
> mnemonics which are no longer useable contact the Network Executive.
> 
> It is hoped that the Gateway will support the  Network  Registration  Scheme
> (NRS) in the near future.
> 
> JANET User Notes 5 and 6 include mnemonics for a number of  remote  machines
> and networks on both PSS and JANET.
> 
> 
> 
> 
> 
> 
> 
> 16 August 1988                                                     Page   11
> 
> 
> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
> 
> 
> _______________________________
> 9.  Facilities Available on PSS
> 
> ________________
> 9.1  Fast Select
> 
> This allows calls to have up to 128 bytes in the Call User Data field.   You
> can use this to expand address information available for the next hop of the
> call.  As  a  PSS  user  we  have  subscribed to this facility;  however you
> should note that some remote Hosts on PSS and IPSS cannot accept Fast Select
> calls.  If a Fast Select call is made to an address which does not subscribe
> to the Fast Select facility the call will fail with clearing  code  Hex'29'.
> 
> 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 the Gateway has to be told 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 just a delimiter which
> will be ignored.
> 
> For example, calling TELENET
> 
>       PSS(FRED,XYZ).NFS-311012345678
> 
> ____________________________
> 9.2  Reverse Charge Facility
> 
> If this facility is used the remote Host will accept all the  call  charges,
> therefore your  allocation  on  the Janet Gateway will not be debited.  Note
> that there are not many remote Hosts which will accept  'reverse  charging'.
> 
> Unfortunately the only way to find out if a remote Host will accept  reverse
> charging is  to  experiment.   Do this by appending 'R' to the authorisation
> field, for example
> 
>      (FRED,XYZ,R)
> 
> If this does not work, it could be because the remote host will only  accept
> calls from 'known' network addresses and the JANET addresses are 'unknown'
> 
> ___________________
> 9.3  Access to IPSS
> 
> It is possible to access  IPSS,  the  International  Packet  Switch  Stream,
> through PSS.   This is done by entering the IPSS address in place of the PSS
> address.  IPSS calls are accounted separately from PSS so you will  have  to
> make a  specific  request  for  an  IPSS allocation before you make calls on
> IPSS.
> 
> ___________________________________________________
> 9.4  Calls to Other, Non-Transport Service Networks
> 
> Some networks (for example, TYMNET) require a Call User Data  Field  with  a
> different format from the 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.  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.
> 
> 
> 
> 16 August 1988                                                     Page   12
> 
> 
> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
> 
> 
> _______
> Example
> 
>      PSS(FRED,XYZ).NFS-31060000*DZRRT;IPSSLON
> 
> This would call a (fictitious) address on TYMMNET.
> 
> Finally some machines do not expect to receive any user data at all, so  you
> will need to enter '*D' on its own for these.
> 
> _______
> Example
> 
>      PSS(FRED,XYZ).YONDER*D
> 
> ___________________________
> 9.5  Adjusting Packet Sizes
> 
> The Gateway normally tries to establish its calls with a packet size of  256
> bytes, even  if  the incoming call had only 128 byte packets.  This normally
> does not cause problems, but there may be difficulties  with  some  systems.
> If you  find  your  call  being  cleared  even  though all the addressing is
> correct, or if it fails as soon as data starts to flow, try calling with the
> additional data, '*P7W2', to force a packet size of 128 bytes.
> 
> _______
> Example
> 
>      PSS(FRED,XYZ).OVERTHERE*P7W2
> 
> If you also need to use the *D parameter that must follow the *P/W paramter.
> 
> _______
> Example
> 
>      PSS(FRED,XYZ).HERE*P7W2*DTOYOU
> 
> ___________________________________________________
> 10.  Protocols Available if Supported by Both Local
>      ________________________
>      and Remote Host Machines
> 
> Other sorts of calls, besides terminal calls, may be  possible  through  the
> Gateway.  In  these  cases  Transport  Service  is required.  The mechanisms
> required for insertion of authorisation information vary  from  computer  to
> computer, and  therefore  your  local  support staff should be consulted for
> information in this area.
> 
> Care needs to be exercised here, especially when replying to MAIL  from  PSS
> without considering  how  the  authorisation  will be managed.  Problems can
> also occur with FTP, which will continue to retry a call until it receives a
> fatal error, causing unnecessary network traffic.
> 
> _____________________________________________________
> 10.1 Network Independent File Transfer Protocol (FTP)
> 
> This allows files from one computer's file store to  be  sent  to  the  file
> store of  another  computer.   Although  the  two  computers  may  have very
> different ways of working internally, FTP will overcome  these  difficulties
> and arrange for the transfer of the file without the user being aware of the
> special procedures that are being carried out.
> 
> 
> 
> 
> 
> 16 August 1988                                                     Page   13
> 
> 
> 
> How to Use the U.K. Academic Network - Packet SwitchStream (PSS) Gateway
> 
> 
> ______________________
> 10.2 JNT MAIL Protocol
> 
> This allows MAIL messages to be sent from one user  to  another  user.   The
> users may  be  using  the same machine or may be using machines on different
> networks.  In both cases the user types his message into the  machine  being
> used and  the MAIL program then adds a header to the message, so that it can
> be transmitted to the remote Host by FTP.  The received message is stored on
> the remote Host and made available to the addressee.
> 
> __________________________________________________
> 10.3 Job Transfer and Manipulation Protocol (JTMP)
> 
> This protocol lets you:
> 
>      transfer files for storage or execution
>      make status enquiries and get reports on these files.
>      modify the progress of the above.
> 
> This protocol requires standard FTP to carry out the transfers.
> 
> ____________________________
> 11.  Restrictions and Errors
> 
> _________________
> 11.1 Restrictions
> 
> Due to the present lack of a full Transport  Service  in  the  gateway,  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 however support continuation of Transport  Service  Connect
> messages into  the  first  data  packet.   This  is particularly useful when
> attempting file transfers for which the  12-byte  CUDF  limitation  pertains
> (i.e.  NSF- calls).
> 
> ___________
> 11.2 Errors
> 
> When a call fails, there is an error code associated with the failure  which
> will normally be displayed on your PAD.  A list of the most common codes and
> their meanings is given in Network User Note 15.
> 
> 
> 
> 
