EPVPN is EVENTPHONE’s permanent, experimental phone network. Think of it as a long-running event where you can stay in touch under your pseudonym between events.

The new EPVPN has been in production since 17 October 2026. The public beta has ended, existing accounts have been migrated, and the old system has been shut down. The platform formerly known as EPVPN Beta is now EPVPN. Read the switchover announcement (DE/EN).

EPVPN supports SIP extensions and features such as call groups, announcements, custom ringback tones and call forwarding within EPVPN. There is no PSTN dial-out.

Call forwarding between EPVPN and temporary events is currently unavailable in both directions.

1. Log in with your EVENTPHONE account or register for one.
2. Select EPVPN in the upper left corner, then open My Extensions. Use an existing extension or choose Add Extension for EPVPN. Please register only extensions you actively use.
3. Configure your SIP client as described below.

• PSTN dial-in: +49 221 59619 XXXX
• VoIP dial-in: sip:XXXX@hg.eventphone.de (dual stack)
  • IPv4-only: sip:XXXX@hg4.eventphone.de
  • IPv6-only: sip:XXXX@hg6.eventphone.de

Replace XXXX with the EPVPN extension you want to call.

• SIP proxy: hg.eventphone.de (dual stack), hg4.eventphone.de (IPv4-only) or hg6.eventphone.de (IPv6-only).
• SIP username: Your extension number, for example 1234.
• SIP password: In GURU3, open My Extensions and click the key icon next to your EPVPN extension.
• SIP port: 5060 for UDP or 5061 for TCP/TLS.
• RTP ports: Dynamically assigned between 10000 and 20000.
• Behind NAT? Configure your SIP client to send keep-alive packets about once a minute.
  • FRITZ!Box: Telephony → Telephone Numbers → Line Settings → Keep port sharing of the internet router enabled for telephony.

EPVPN has its own dial plan. The numbering and routing rules differ from those at temporary EVENTPHONE events.

• From EPVPN to a temporary event: While the event is running, dial 09 followed by the event extension.
• From a temporary event to EPVPN: Dial 01999 followed by the EPVPN extension.

• 0… → prefixes and routing
• 0310 → network announcement
• 1xxx → reserved for hackerspaces. Contact us if you need a number in this range.
  • 16xx → reserved for VOC
• 20xx → reserved for PoC
• 2100–7999 → user extensions
• 8xxx → IVRs, scripts, announcements and automated responses
• 9xxx → prefixes and routing

You can configure 01999 as a local prefix for EVENTPHONE on devices that route calls to different VoIP providers based on the dialled prefix, such as a FRITZ!Box. EPVPN strips the prefix before routing the call. For example, 01999-0310 is routed to 0310, the EPVPN network announcement.

The German numbering plan designates the (0)199 range for internal network routing. See section 3(g) of the Bundesnetzagentur numbering plan for traffic routing numbers.

See also the online EPVPN phonebook. If GURU3 shows another event’s phonebook, select EPVPN in the event picker.

• LDAP
• CardDAV

We regularly delete accounts whose registered email addresses can’t receive mail and release extensions that haven’t been used for more than a year.

Please check that you can receive mail at the address registered in GURU3 and release any extensions you no longer need.

EPDDI is available only at temporary events. EPVPN does not offer EPDDI.

Offering EPDDI on EPVPN would require us to purchase a license we do not currently hold, build a multi-OMM setup, and operate and maintain a permanent SIP-DECT installation. We’ve decided against taking on the licensing costs and ongoing maintenance.

• If your SIP client fails to register, check the server and the credentials for your EPVPN extension in GURU3.
• To test your connection, dial 0310 for the EPVPN network announcement.
• If you need help, contact GURU3 support.

• 2009-12-04: First successful test call.
• 2009-12-18: First successful NAT-to-NAT test call.
• 2009-12-18: Start of public testing.
• 2009-12-27 to 2009-12-30: Extensive testing at 26C3.
• 2010-02-01: Public testing ended and the original setup went live.
• 2012-09-17: Migration to new VoIP server software.
• 2013-02-05: SIP over TLS and SRTP added on hg.eventphone.de, port 5061.
• 2016-10-14: Operation confirmed.
• 2019-04-23: Operation confirmed.
• 2019-10-29: Brief outage during the upgrade from Debian 7 to Debian 10.
• 2020-06-10: Let’s Encrypt certificates added on port 5061.
• 2025-03-08: First successful test call on the new platform.
• 2025-04-21: Public beta of the new platform began.
• 2026-10-17: The new platform entered production as EPVPN. Existing accounts were migrated and the previous system was shut down.