TL;DR

• Registration is open – register your number in Guru3
• Don’t forget your phone (ISDN, DECT, GSM, SIP)
• Remember batteries, charging cables, and CCC SIM card
• There will be eSIMs for the GSM network
• The dial-in number from outside is: +49 40 5730830 xxxx

Preparations for 39C3 are already in full swing. You have already registered more than 5,600 extensions. We are very excited. We would like to take this opportunity to provide some information about telephony at 39C3 and have compiled the following details on all the technologies you can use to participate in the Congress telephone …