<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><div>On 10 Feb 2013, at 01:34, Erik Kline <<a href="mailto:ek@google.com">ek@google.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><blockquote type="cite">I certainly know that it's doable, I'm more curious to know how much the two can differ (ULA, PD, PI, privacy, etc.). I'm looking into using two prefixes because of the privacy options ($WORK is health care, so some data is highly sensitive), but there may be other reasons to use two prefixes.<br></blockquote><br>I believe I would just use privacy/temporary addresses by default, and<br>pull MAC<->L3 mappings off the switches/routers for the purposes of<br>auditing. That way you're more likely to notice when someone changes<br>IP addresses (IPv6 or otherwise).<br></blockquote><br></div><div>This is I think what most campus enterprises are doing. It's certainly exactly what we do here. </div><div><br></div><div>Below is a snapshot for the last 7 days for one of my devices, searching by Ethernet address, and listing the switch ports and IPv4/IPv6 addresses, including privacy addresses, that have been observed through polling devices as Erik suggests. This is using NAV, which is a nice open source package we have run for a while now. It's developed by the Norwegian academic network team at UNINETT. But I'm sure other packages are quite capable of doing this too. Or they should be!</div><div><br></div><div>The example below shows the device's link local IPv6 address in use for the whole time period, along with the IPv4 address, and IPv6 privacy addresses changing over time. Note the EUI-64 doesn't actually show up, presumably since nothing connects *to* this device by its static global address, and it only uses its current privacy address to initiate connections externally.</div><div><br></div><div>Apologies if the format is a bit odd for non graphic UIs :)</div><div><br></div><div><div id="navbody" style="margin: 0px; padding: 0px; font-family: Arial, Helvetica, sans-serif; font-size: 13.513513565063477px; "><div class="tabcontent" style="margin: 0px 0px 1em; padding: 1em; border: 1px solid rgb(153, 153, 153); position: static; z-index: auto; "><div class="results" style="margin: 0px; padding: 0px;"><table class="listtable" style="border: 1px solid rgb(153, 153, 153); caption-side: top; margin-bottom: 1em; position: static; z-index: auto; "><caption style="text-align: left; background-color: rgb(86, 120, 153); color: white; border-bottom-width: 2px; border-bottom-style: solid; border-bottom-color: white; font-size: 1.2em; padding: 0.3em 0.5em; ">MAC Search results<br><span class="subtitle" style="font-size: 0.9em; ">2 hits</span></caption><thead><tr style="text-align: left; vertical-align: top;"><th colspan="2" style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">Switch</th><th style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">Module</th><th colspan="2" style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">Interface</th><th style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">Start time</th><th style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">End time</th><th style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">Mac</th></tr></thead><tbody><tr class="oddrow" style="background-color: white; text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/swp/?switch=b32-l3-cat1.ecs.soton.ac.uk&module=&port=&days=7" title="Search for other machines on this switch" style="color: rgb(45, 90, 134); text-decoration: initial;">b32-l3-cat1.ecs.soton.ac.uk</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/b32-l3-cat1.ecs.soton.ac.uk/" title="Browse this switch (IP Device Info)" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Device info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/swp/?switch=b32-l3-cat1.ecs.soton.ac.uk&module=&port=Gi4/0/44&days=7" title="Search for other machines on this port" style="color: rgb(45, 90, 134); text-decoration: initial;">Gi4/0/44</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/b32-l3-cat1.ecs.soton.ac.uk/ifname=Gi4/0/44/" title="Browse this interface (IP Device Info)" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-06 12:23</td><td style="margin: 0px; padding: 0.1em 0.5em;">Still active</td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/mac/?mac=c8:2a:14:20:24:71&days=7&dns=" title="Search for this MAC address" style="color: rgb(45, 90, 134); text-decoration: initial;">c8:2a:14:20:24:71</a></td></tr><tr class="evenrow" style="background-color: rgb(246, 246, 246); text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-05 16:53</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-06 11:25</td><td style="margin: 0px; padding: 0.1em 0.5em;"></td></tr></tbody><tfoot><tr style="text-align: left; vertical-align: top;"><th colspan="0" style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">2 hits</th></tr></tfoot></table></div><div class="results" style="margin: 0px; padding: 0px;"><table class="listtable" style="border: 1px solid rgb(153, 153, 153); caption-side: top; margin-bottom: 1em; "><caption style="text-align: left; background-color: rgb(86, 120, 153); color: white; border-bottom-width: 2px; border-bottom-style: solid; border-bottom-color: white; font-size: 1.2em; padding: 0.3em 0.5em; ">IP search results<br><span class="subtitle" style="font-size: 0.9em; ">16 hits</span></caption><thead><tr style="text-align: left; vertical-align: top;"><th style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">IP</th><th style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; "></th><th style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">MAC</th><th style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">Start time</th><th style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">End time</th></tr></thead><tbody><tr class="oddrow" style="background-color: white; text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/ip/?ip_range=152.78.65.110&days=7&dns=&active=on" title="Search for this IP address" style="color: black; ">152.78.65.110</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/ip=152.78.65.110/" title="Lookup this IP in IP Device Info" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/mac/?mac=c8:2a:14:20:24:71&days=7&dns=" title="Search for this MAC address" style="color: rgb(45, 90, 134); text-decoration: initial;">c8:2a:14:20:24:71</a></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-05 16:51:57</td><td style="margin: 0px; padding: 0.1em 0.5em;">Still active</td></tr></tbody><tbody><tr class="evenrow" style="background-color: rgb(246, 246, 246); text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/ip/?ip_range=2001:630:d0:f111:5420:e84f:86fe:c3e5&days=7&dns=&active=on" title="Search for this IP address" style="color: rgb(45, 90, 134); text-decoration: initial;">2001:630:d0:f111:5420:e84f:86fe:c3e5</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/ip=2001:630:d0:f111:5420:e84f:86fe:c3e5/" title="Lookup this IP in IP Device Info" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/mac/?mac=c8:2a:14:20:24:71&days=7&dns=" title="Search for this MAC address" style="color: rgb(45, 90, 134); text-decoration: initial;">c8:2a:14:20:24:71</a></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 16:22:01</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-10 19:51:58</td></tr></tbody><tbody><tr class="oddrow" style="background-color: white; text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/ip/?ip_range=2001:630:d0:f111:943b:a03b:38ac:8b0&days=7&dns=&active=on" title="Search for this IP address" style="color: rgb(45, 90, 134); text-decoration: initial;">2001:630:d0:f111:943b:a03b:38ac:8b0</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/ip=2001:630:d0:f111:943b:a03b:38ac:8b0/" title="Lookup this IP in IP Device Info" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/mac/?mac=c8:2a:14:20:24:71&days=7&dns=" title="Search for this MAC address" style="color: rgb(45, 90, 134); text-decoration: initial;">c8:2a:14:20:24:71</a></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-07 16:52:08</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-08 20:22:00</td></tr></tbody><tbody><tr class="evenrow" style="background-color: rgb(246, 246, 246); text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/ip/?ip_range=2001:630:d0:f111:a83e:a90c:2760:f20c&days=7&dns=&active=on" title="Search for this IP address" style="color: rgb(45, 90, 134); text-decoration: initial;">2001:630:d0:f111:a83e:a90c:2760:f20c</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/ip=2001:630:d0:f111:a83e:a90c:2760:f20c/" title="Lookup this IP in IP Device Info" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/mac/?mac=c8:2a:14:20:24:71&days=7&dns=" title="Search for this MAC address" style="color: rgb(45, 90, 134); text-decoration: initial;">c8:2a:14:20:24:71</a></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-10 02:21:59</td><td style="margin: 0px; padding: 0.1em 0.5em;">Still active</td></tr><tr class="oddrow" style="background-color: white; text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 19:52:03</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-10 01:51:59</td></tr><tr class="evenrow" style="background-color: rgb(246, 246, 246); text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 13:52:01</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 17:51:58</td></tr><tr class="oddrow" style="background-color: white; text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 09:22:03</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 13:21:57</td></tr><tr class="evenrow" style="background-color: rgb(246, 246, 246); text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 01:21:58</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 07:51:57</td></tr><tr class="oddrow" style="background-color: white; text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-08 07:52:01</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 00:21:56</td></tr><tr class="evenrow" style="background-color: rgb(246, 246, 246); text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-07 22:21:59</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-08 07:21:56</td></tr><tr class="oddrow" style="background-color: white; text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-07 09:21:58</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-07 20:51:58</td></tr><tr class="evenrow" style="background-color: rgb(246, 246, 246); text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;"></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-05 16:51:57</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-07 08:21:57</td></tr></tbody><tbody><tr class="oddrow" style="background-color: white; text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/ip/?ip_range=2001:630:d0:f111:bde3:17c9:1ac8:af3a&days=7&dns=&active=on" title="Search for this IP address" style="color: rgb(45, 90, 134); text-decoration: initial;">2001:630:d0:f111:bde3:17c9:1ac8:af3a</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/ip=2001:630:d0:f111:bde3:17c9:1ac8:af3a/" title="Lookup this IP in IP Device Info" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/mac/?mac=c8:2a:14:20:24:71&days=7&dns=" title="Search for this MAC address" style="color: rgb(45, 90, 134); text-decoration: initial;">c8:2a:14:20:24:71</a></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-10 16:22:02</td><td style="margin: 0px; padding: 0.1em 0.5em;">Still active</td></tr></tbody><tbody><tr class="evenrow" style="background-color: rgb(246, 246, 246); text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/ip/?ip_range=2001:630:d0:f111:edee:ce84:c7f1:4dfa&days=7&dns=&active=on" title="Search for this IP address" style="color: rgb(45, 90, 134); text-decoration: initial;">2001:630:d0:f111:edee:ce84:c7f1:4dfa</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/ip=2001:630:d0:f111:edee:ce84:c7f1:4dfa/" title="Lookup this IP in IP Device Info" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/mac/?mac=c8:2a:14:20:24:71&days=7&dns=" title="Search for this MAC address" style="color: rgb(45, 90, 134); text-decoration: initial;">c8:2a:14:20:24:71</a></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-06 16:51:55</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-07 20:51:58</td></tr></tbody><tbody><tr class="oddrow" style="background-color: white; text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/ip/?ip_range=2001:630:d0:f111:f5c4:fe31:6493:eaec&days=7&dns=&active=on" title="Search for this IP address" style="color: rgb(45, 90, 134); text-decoration: initial;">2001:630:d0:f111:f5c4:fe31:6493:eaec</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/ip=2001:630:d0:f111:f5c4:fe31:6493:eaec/" title="Lookup this IP in IP Device Info" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/mac/?mac=c8:2a:14:20:24:71&days=7&dns=" title="Search for this MAC address" style="color: rgb(45, 90, 134); text-decoration: initial;">c8:2a:14:20:24:71</a></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-08 16:51:59</td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-09 20:21:58</td></tr></tbody><tbody><tr class="evenrow" style="background-color: rgb(246, 246, 246); text-align: left; vertical-align: top; "><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/ip/?ip_range=fe80::ca2a:14ff:fe20:2471&days=7&dns=&active=on" title="Search for this IP address" style="color: rgb(45, 90, 134); text-decoration: initial;">fe80::ca2a:14ff:fe20:2471</a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/ipdevinfo/ip=fe80::ca2a:14ff:fe20:2471/" title="Lookup this IP in IP Device Info" style="color: rgb(45, 90, 134); text-decoration: initial;"><img src="http://nav2.ecs.soton.ac.uk/images/arpcam/ipinfolink.png" alt="IP Info search" style="border: 0px; vertical-align: middle;"></a></td><td style="margin: 0px; padding: 0.1em 0.5em;"><a href="http://nav2.ecs.soton.ac.uk/machinetracker/mac/?mac=c8:2a:14:20:24:71&days=7&dns=" title="Search for this MAC address" style="color: rgb(45, 90, 134); text-decoration: initial;">c8:2a:14:20:24:71</a></td><td style="margin: 0px; padding: 0.1em 0.5em;">2013-02-05 16:51:55</td><td style="margin: 0px; padding: 0.1em 0.5em;">Still active</td></tr></tbody><tfoot><tr style="text-align: left; vertical-align: top;"><th colspan="0" style="margin: 0px; padding: 0.3em 0.5em; background-color: rgb(238, 238, 238); vertical-align: middle; ">16 hits</th></tr></tfoot></table></div></div></div><div id="footer" style="margin: 0px; padding: 0px; clear: both; font-size: 13.513513565063477px; text-align: center; font-family: Arial, Helvetica, sans-serif; "></div></div><div><br></div><div><br></div><div>Tim</div><br></body></html>