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@@ -79,6 +79,53 @@ Coordination of volunteers and angels. Contact for all angels and crews to manag
 
 ## POC
 ## GSM
+
+
+## ISDN (and POTS)
+
+We are planning to operate an experimental ISDN and analog telephony network.
+
+The subscriber lines will be terminated using de-commissioned V5_Access_Multiplexers that were donated by telecom operators together with the osmo-v5 protocol stack and osmo-cc.
+
+This network will be provided for people to re-enact the good old telephony days, using anything as old as rotary dial phones, up to the 1990s ISDN experience.
+
+So if you still have your old wired telephones or ISDN equipment in a basement, feel free to bring it along and hook it up.
+
+### How to connect to the network?
+
+#### Types of interfaces
+
+We can offer
+
+* analog POTS ports, exposed as classic 2-wire "ab" interface according to German standards.
+* ISDN ports using Uk0 interface, using 4B3T according to German standards
+
+#### What Equipment do I need to bring?
+
+For analog lines, you can connect any analog phone, answering machine, fax, modem, etc. Even rotary phones from Sweden and New Zealand (with their special pulse sequences) will work.
+
+For ISDN lines, you should bring your NTBA/NT1 (to convert Uk0 to S0) and then any ISDN equipment like phones, ISDN adapters, PBXs, ... .
+
+If you only have ISDN equipment for S0-bus but no NTBA, we have a few NTBA around that we can lend you, as needed, on a first-come-first-serve basis.
+
+In addition, it is wise to bring sufficient length of telephony wires so you can connect to the closest "Point of Presence".
+
+#### Where can I connect to the network?
+
+You would need to run some telephony wire (or CAT5, if that's all you have) to one of our "points of presence", where we will put V5_Access_Multiplexers.
+
+We are planning to deploy those at only a few (2-3) "Datenklo" around the camp site. One of them will be in the vicinity of the PoC tent, the other locations are yet to be determined.
+
+#### What kind of services do you offer?
+
+Our experimental analog + ISDN network will be interconnected with the PoC/eventphone so you should be able to connect not only with other users of the analog/ISDN network, but also the PoC DECT subsribers, as well as the c3gsm GSM subscribers.
+
+There might also be connectivity with the OCTOI network, but we are uncertain if we can achieve that.
+How to contact you.
+
+Contact details on how to reach the ISDN team will be provided ahead of the camp.
+
+
 ## Network
 
 As usual there will be wired and wireless connectivity avaible.