The i-Telex device modules enable connection to other TTYs that use the i-Telex protocol. The software splits into the client part and the server part. The client part handles outgoing connections, the server part is responsible for incoming connections.

Outgoing connections are handled by the Client part.

When the module is enabled in the config file with the default values, you should be instantly able to connect to every i-Telex client as long as your piTelex knows the hostname and port of the remote system. The transformation from the subscriber number you dial to hostname:port of the remote system is done in a first step via local "phonebook" that defaults to userlist.csv in the piTelex directory. If there is no matching entry, piTelex tries to resolve the request via internet connection to the "TNS" dictionary server network (TNS = "TeilNehmerServer" = subscriber server). Without connection to the internet your local phonebook allows you to connect to i-Telex devices in your local LAN.

An example of the required file structure of userlist.csv is given in userlist_example.csvin the piTelex directory. userlist.csvcan also be used for speed dials, as entries in this local phonebook always take precedence over TNS queries. But be aware not to use shortcuts that overlap with real i-telex subscriber numbers. If you have a shortcut "83" in your userlist.csv that resolves to a specific hostname, all numbers starting with "83" will be masked and become unreachable.

There are several variants of how piTelex evaluates and processes the dialled number. This can be configured via the global parameter dial_timeout and is described in SW_ConfigJSON#dialing.

Incoming connections require the server part to be active, which is the default setting; to disable incoming connections, set port to zero.

Your piTelex instance will be reachable by every i-Telex client which knows hostname (or IP address) and configured port of your piTelex system. If the remote station is a piTelex system, it could add your number and hostname:port to it's local userlist.csv in order to reach you via telex number dialled at the remote station.

The more sleeky way is to get an entry in the "TNS", so that you can be reached via regular "telex number". For this you have to contact the i-Telex admins and send them a telex to one of the telex numbers

• 925302 (Fernschreibzentralzeugamt Blumenhagen)
• 952996 (Fernschreibzentrale Rödental)

and include the following information:

• your name and location (city)
• your telex id (answerback) (e.g. 123456 mytelex d)
• Desired subscriber number (at least five digits; should be the first part of your telex id, if possible)
• machine type (e.g. "Siemens T100")
• IPv4 address and port of your piTelex system (or address:port of your router, if piTelex is behind it)
• address mode (static, dynamic), see below

You will receive a confirmation message after the entry has been created.

none

  "i-Telex": {
      "type": "i-Telex",
      "enable": true,
      "port": 2342,
      "tns_dynip_number": 833788,
      "tns_pin": 12345
    },