I guess 'interruption' is defined by 'being offline after X minutes pass'.

Yes, the tunnel must really ping. It is not enough that your ipv6 connection is working. Besides, as reported by other users, in certain cases the aiccu makes you think that it is having a connection, without reaching ipv6 connectivity (aiccu remains in the tray answering heartbeats but cannot configure properly the ipv6 connection). So, the first thing to do is take care that ipv6 connectivity is really working (e.g., visit some sixxs.org webpage, and if you see below that webpage your ipv4 ip address, then ipv6 connectivity is NOT working. If you see below it an ipv6 address (e.g. "SSL IPv6 connection from ..................") then ipv6 connectivity is working. If the sixxs.org webpage takes too long to load, then ipv6 connectivity is not working either. Then, you have to care that your ipv6 endpoint is answering pings with an icmp echo. I advise to enable ping echo (icmp echo) in your router AND in your Windows firewall (or whatever firewall you use). Inside the FAQ, it is explained that if your ipv6 endpoint answers at least one ping during each (and every) day of one week (or two weeks, maybe), that counts as 5 extra credits. E.g., I have a perfect AYIYA connection through a dynamic tunnel with Windows 2003 SP1, default firewall activated, icmp echo enabled for all network connections, through a router that does not support any ipv6 protocol and it does not support proto-41. I disabled router's option of ignoring ping from WAN and I enabled all other options of router's protection against DDOS, Ping of Death and so on. The NAT firewall of the router is activated and router's UPnP is activated. I have neither demillitarized zones nor port forwarding of any sort.

I had a similar problem. It turned out that my firewall was dropping the stateful rules for the tunnel after periods of no activity. I finally scheduled a cron on the machine with the tunnel endpoint to ping6 www.kame.net every 5 minutes. This has kept the tunnel alive and earning points for about 6 weeks now. According to the FAQ: --- Every PoP tests your connection by pinging using ICMPv6 packets from the PoP's IPv6 endpoint to your IPv6 tunnel endpoint. One way to easily find out if you have a setup problem is by doing a tcpdump and pinging the PoP's endpoint and checking if you see a response coming back if that's the case leave your tcpdump running and see if you get the 20 ping's which are sent every 15 minutes. Thus you have 24 * 4 * 20 = 1920 pings the chance to be up every day. --- I don't know if dynamic tunnels just have to ping once in a day or every time pings are sent in order to be considered up.