I have read and followed the "Reporting Problems" section on the Contact page and am providing the following details for this report based on the list of items stated there: Hi. NIC handle MNC2-SIXXS Running a static 6to4 tunnel from 150.101.89.3. My understanding was that the v6 address that'd be allocated to the tunnel would be a /64. I have 2a01:348:6:4e::2 at my end, so that'd mean I'd be able to set up my tunnel end point as a router with reachability to anything that started with 2a01:348:6:4e::/64. However -- from 2001:44b8:f020::1, a traceroute yields the following: bdr1.sjc2>traceroute 2a01:348:6:4e::3 Type escape sequence to abort. Tracing the route to 2A01:348:6:4E::3 1 ge-3-7.r02.snjsca04.us.bb.gin.ntt.net (2001:418:0:5000::8D) 140 msec 104 msec 4 msec 2 ae-2.r20.snjsca04.us.bb.gin.ntt.net (2001:418:0:2000::12D) 0 msec 0 msec 0 msec 3 p64-1-3-0.r21.chcgil09.us.bb.gin.ntt.net (2001:418:0:2000::1BA) 56 msec 56 msec 60 msec 4 ae-0.r20.chcgil09.us.bb.gin.ntt.net (2001:418:0:2000::35) 56 msec 60 msec 56 msec 5 p64-0-0-0.r21.nycmny01.us.bb.gin.ntt.net (2001:418:0:2000::BE) 84 msec 84 msec 164 msec 6 p64-2-1-0.r22.londen03.uk.bb.gin.ntt.net (2001:418:0:2000::10E) 164 msec 164 msec 164 msec 7 xe-4-4.r01.londen03.uk.bb.gin.ntt.net (2001:728:0:2000::11A) 164 msec 164 msec 164 msec 8 po-0.goscomb.londen03.uk.bb.gin.ntt.net (2001:728:1C00:5000::26) 172 msec 176 msec 168 msec 9 gblon02.sixxs.net (2A01:348:0:4:0:3:1:1) !U !U !U (of course, tracerouting to :1 and :2 works) Is my understanding incorrect? Is the tunnel actually carrying a /126 instead of a /64 ? Thanks, - mark