SixXS::Sunset 2017-06-06


The SixXS software, the parts that run on the PoPs and is used for management has undergone a number of behind the scenes changes. The news pages also record a number of these events. Development is mostly an evolutionary process: design, initial implementation, design adjustment, modification, alpha test, missing feature addition, beta test, and finally deployment. After these minor changes, bug fixes and add-ons will be made. Re-designs or large improvements will only be brought into a new release.
Development:early 2000 - 2001-05-10
Deployed:2000-08-21 - 2002-10-23 was the first tunnel broker that the SixXS team ran. It was setup as a hobby project by Pim van Pelt and Cliff Albert around the beginning of 2000. Jeroen Massar joined near the end of 2000. This version is tagged v0 as it didn't carry the name SixXS then but it was a very good initial starting point with many lessons learnt from this project being a basis for the SixXS setup. The software for controlling the tunnelbroker consisted out of a number of shell scripts. Only a single PoP, which also ran the database and the website, was available and users had to signup per email being as polite as possible to get a tunnel and subnet. This software only allowed static tunnels and subnets.

The project ended 2004-06-06 decommissioning the PoP which ran for nearly four years.

There is a snapshot of the website available on's Wayback Machine:

Development:2001-05-03 - 2001-10-28

This was the first setup of SixXS. The target was to make a distributed tunnel broker where users could get tunnels to multiple physically separated PoPs, thus allowing failover and also allowing the user to choose the closest server in a method they wished, using one block of address space. During a brainstorming and design session at Pim's then house in Best we came up with the name SixXS, though at first it was spelled with both the X's in caps, later on it was decided to only capitalize the last X. Due to time constraints this version got into the abandoned state, also because we realized that there would be scalability issues with the design we had in mind.

There is a snapshot available of the website on's Wayback Machine: SixXS v1

Development:2002-05-17 - 2005-12-01
Deployed:2002-10-23 - 2006-02-20

As the setup took a lot of time to run, Pim and Jeroen came together in Belgium, where Pim was living at that time, and started designing a new system: SixXS v2. Due to even longer experience with and knowing the ins and outs of all the current problems a new system was designed that would be extendible and modular making the system future proof. The Tunnelbroker started running this software and was then fully integrated into the SixXS system. The v2 system has been extended a couple of times, providing features like dynamic tunnels which where not planned yet in the original version. GRH is also integrated into the system.

Development:2005-03-04 - 2009-12-31
Deployed:2006-01-09 - 2011-07-07

Due to growth and also the need to keep on enhancing we've developed the third version of SixXS. It brought full support for AYIYA.

Development:2010-01-01 - 2017-06-06
Deployed:2011-07-07 - 2017-06-06

For sixxsd v4 the primary focus lies with scalability and error reporting.

For the website the primary focus is on the signup process and user handling. The signup process will be changed so that users provide a name+country and can directly login with the password they receive. Then they can opt to request tunnel/subnet service by providing their full valid details and having these be verified by the SixXS Staff. Bounced emails, address/phone updates, also after rejection, can then be updated through the webinterface.

Offload functionality to the PoPs so that the systems become more resilient to outages. A new monitoring system will also be put in place allowing better diagnosis and even notification to users directly what problem they most likely have with their tunnel setup.

¹ Development: that new features are added and the existing code maintained to fix bugs.
Static Sunset Edition of SixXS
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