Rail connection system
In the foreground the place-name transmitter and the call and signal machine .
Railway self-connection systems ( BASA for short ) were telephone networks of Central European railway administrations, e.g. B. the ÖBB or the German railways . These administrative, non-public networks were each among the largest independent telecommunications networks in the respective countries. The abbreviation BASA is still a common term among railway workers to e.g. B. to differentiate internal numbers from public ones.
BASA in Germany
The BASA of the former Deutsche Bundesbahn was one of the largest independent telecommunication networks ( fixed network ) in Germany with 120,000 subscriber lines .
history
At a time when telecommunications sovereignty was constitutionally with the state telecommunications authority of the Post, the legislature for the first time consistently granted the Deutsche Reichsbahn the right to set up and operate its own telecommunications business network with the Telecommunications Systems Act of January 14, 1928 . In practical terms, the term “self-connection” refers to the waiver of a manual switching center in switching traffic. This self-dialing operation in the local and long-distance network could be implemented much earlier on the railways than in the public telephone network of the Reichspost , because here there was no need to calculate charges.
The first highways were built by a subsidiary of the Deutsche Reichsbahn. The BASA network of the Deutsche Reichsbahn consisted of lines along the routes as well as lines on motorways, which are no longer used for rail purposes today.
The BASA lines were initially designed as overhead lines parallel to the telecommunication cables, but were laid underground at the latest when the lines were electrified. Overhead lines that still exist on branch lines are only rarely used for the purposes of BASA operations.
In order to increase security in the BASA network, there were cross-connections between the exchanges in addition to the conventional network structure , with which connections could be established while bypassing the main exchanges . On the one hand, if a main exchange failed, one or more cross-connections could reach other main exchanges, and on the other hand, the main exchanges were relieved. Which exchange had been reached could be seen from an acoustic signal that was transmitted either as a single Morse code or as a spoken word. In the BASA network, for security reasons, it was possible right from the start to end an existing call from the called subscriber (back release). In other (analog) telephone networks at the time, the connection remained in place until the caller hung up.
In addition to telephones, other subscriber facilities such as Hellschreiber , telex and fax as well as systems for data transmission were part of the BASA network . The telecommunications service of the Federal Railroad also operated its own radio link .
The BASA network was spun off on the occasion of the restructuring of Deutsche Bahn . The telecommunications company Arcor was initially created from the existing telephone network by merging the companies CNI and DB-Kom GmbH & Co. KG . The telephone network was modernized to ISDN technology and partially marketed.
In the spring of 2001, Deutsche Bahn demanded the return of the network that had been handed over to Arcor in 1997 after the annual fees for the former railway's own communications systems had far exceeded the purchase price. At the time of the takeover, DB had undertaken to only use Arcor communication services for ten years. Around a third of Arcor's sales of more than three billion DM at that time was made up by the railway sector. In order to emphasize the demand, the DB rejected Arcor's planned IPO since the end of 2000.
The internal telecommunications network is currently operated by the Deutsche Bahn subsidiary DB Systel GmbH.
Between 2008 and 2019, all BASA connections were gradually migrated to IP technology.
Historical technology (before digitization)
Switching systems of the Deutsche Reichsbahn
- EB 1 - 1923 to 1927 Strowger selector, switching speed 33 / s
- EB 2 - not introduced
- EB 3 - new large railway system, rotary lever dial , switching speed 60 / s
- EB 4 - new small railway system (Klein-BASA)
- EB 5 - single basement, from 1935
- EB 6 - motor selector, switching speed 80 to 200 / s (with the DR no precious metal contact motor rotary selector )
- EB 7 - MSN 70 (middle switch, private branch exchange with 70 participants)
- EB 8 - ATZ 65 N + B (automatic switchboard 65 mobile PBX, train), crossbar
Technical implementation of the mediation
- "Small BASA" for a maximum of 10 participants (mostly over 7x and participant numbers from 1 to 10)
- "Basa district" only for the Deutsche Reichsbahn, several participants were connected in parallel on a twin wire by inductive dialing.
- "100-BASA" for a maximum of 100 participants
- "1,000-BASA" for a maximum of 1,000 subscribers (mostly numbers such as 81x to 89x and subscriber numbers from 001 to 999 possible)
- "10,000-BASA" (also large BASA) for a maximum of 10,000 subscribers (mostly 800 to 809 and subscriber numbers 0001 to 9999 possible)
Special numbers
- 100 - fault location (1000 for large switching systems)
- 510 - Fault location at the Deutsche Reichsbahn in the former West Berlin in the BASA office Berlin-Charlottenburg
- 111 - switching / information (with large switching systems 1111) (this number combination was chosen so that the switch could be reached with the hook switch in the event of a defective dial )
- 8111 - time announcement (last only available in Berlin; no longer in operation today), was particularly important because there was an operating regulation that stipulated that every railway worker must have access to the exact time.
Number blocks
- 0 = digit for accessing an outside line to the public network, but sometimes also possible with an earth key
- 1 to 6 = normal phone numbers, whereby the 1 and the 6 should not be carried out as "officially authorized"
- the 2 should be used for administration and workshop numbers
- 3, 4 and 5 should be used for offices with public traffic or with a lot of telephone traffic in the postal network
- the 1 and the 6 should be used as pure BASA numbers for pure operating locations
- at the Deutsche Reichsbahn, the number 6 was used to dial into company lines
- (This division, however, was hardly achieved "purely", since the restructuring after the Second World War had to resort to makeshifts and these remained in place)
- 7 = "Speed dial" to a small BASA or "cross connection" between two BASAs
- 8 = select BASA in your own district (e.g. 812 for Essen, 803 for Soest)
- 9 = Dial-up network, you always had to dial your own district node (e.g. Essen 812) first, in order to then dial the next major node (e.g. Munich 962). From here you dialed the BASA (e.g. Erding 845) again.
A major advantage of the BASA network to this day is that most of the phone numbers are still functionally assigned. Without knowing the person's name, you can contact the responsible authorities at the respective location.
- 22, 222 or 2222: dispatcher of the respective train station
- 365 or 1365 or 3365: locomotive line of the respective depot
- 391 station board, today usually the first district manager
- 393 Telecommunications mastery of the district
- 395 railway master
- 397 Signal service
- 1000 telecommunication suppression points of the respective basa
- 1055 3-S headquarters
- 2000 fault clearance agency DB-Netz (EVZS)
- 911-91 time announcement
literature
- Short dictionary of electrical telecommunications : published on behalf of the Federal Ministry for Post and Telecommunications; Revised edition, Bundesdruckerei Berlin, 1970, volumes A – F; Pp. 123-124
Individual evidence
- ↑ Report by rail calls for telecommunications network back . In: Eisenbahn-Revue International , issue 5/2001, ISSN 1421-2811 , p. 196.