All headers and filter headers are encoded with an arbitrary two byte prefix (currently "2001:"), followed by a 0-indexed order nibble (as nameservers often reorder responses). Bitcoin headers are then prefixed by a single 0 byte (two 0 nibbles) and placed into the remaining 80 bytes of six IPv6 addresses. Filter headers are simply placed into three IPv6 addresses with a 17-nibble (8.5 byte) 0 suffix.
</p>
<p>
All headers and filter headers are encoded with an arbitrary two byte prefix (currently "2001:"), followed by a 0-indexed order nibble (as nameservers often reorder responses). Bitcoin headers are then prefixed by a single 0 byte (two 0 nibbles) and placed into the remaining 80 bytes of six IPv6 addresses. Filter headers are simply placed into three IPv6 addresses with a 17-nibble (8.5 byte) 0 suffix.
</p>
<p>
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:0:1000::
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:1000::
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:2000::3ba:3edf
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:3d7a:7b12:b27a:c72c:3e67:768f:617f
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:4c81:bc38:88a5:1323:a9fb:8aa4:b1e5
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:0:1000::
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:1000::
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:2000::3ba:3edf
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:3d7a:7b12:b27a:c72c:3e67:768f:617f
0.0.bitcoinheaders.net. 604800 IN AAAA 2001:4c81:bc38:88a5:1323:a9fb:8aa4:b1e5
-0.0.bitcoinheaders.net. 604800 IN AAAA 2001:5e4a:29ab:5f49:ffff:1d:1dac:2b7c
-which decodes to
-0100000000000000000000000000000000000000000000000000000000000000000000003ba3edfd7a7b12b27ac72c3e67768f617fc81bc3888a51323a9fb8aa4b1e5e4a29ab5f49ffff001d1dac2b7c
- </pre>and the first filter header encoded as:<pre>
+0.0.bitcoinheaders.net. 604800 IN AAAA 2001:5e4a:29ab:5f49:ffff:1d:1dac:2b7c</pre>
+ <p>which decodes to</p>
+ <p class="hex">
+ 0100000000000000000000000000000000000000000000000000000000000000000000003ba3edfd7a7b12b27ac72c3e67768f617fc81bc3888a51323a9fb8aa4b1e5e4a29ab5f49ffff001d1dac2b7c
+ </p>
+ <p>and the first filter header encoded as:</p>
+ <pre>
0.0.basic.filter.bitcoinheaders.net. 604800 IN AAAA 2001:9f3:c30f:c37:fb97:7cf3:e1a3:173c
0.0.basic.filter.bitcoinheaders.net. 604800 IN AAAA 2001:2802:139c:2020::
0.0.basic.filter.bitcoinheaders.net. 604800 IN AAAA 2001:9f3:c30f:c37:fb97:7cf3:e1a3:173c
0.0.basic.filter.bitcoinheaders.net. 604800 IN AAAA 2001:2802:139c:2020::
-0.0.basic.filter.bitcoinheaders.net. 604800 IN AAAA 2001:1631:e8ff:119a:d308:8b6f:5b2b:ced0
-which decodes to 9f3c30f0c37fb977cf3e1a3173c631e8ff119ad3088b6f5b2bced0802139c202
- </pre>
+0.0.basic.filter.bitcoinheaders.net. 604800 IN AAAA 2001:1631:e8ff:119a:d308:8b6f:5b2b:ced0</pre>
+ <p>which decodes to</p>
+ <p class="hex">
+ 9f3c30f0c37fb977cf3e1a3173c631e8ff119ad3088b6f5b2bced0802139c202