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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><o:p> </o:p></p><p class=MsoPlainText>Hello,<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>We are deploying IPV6 to our customers and are carefully planning the architecture of how we are going to deploy prefixes, assign customer gateways and how we are going to number our own infrastructure in a meaningful way. Although I think Stateless Autoconfiguration will be used quite a deal for nodes that are "clients", most of my customers have large server farms and our infrastructure, of course, has many routers. I would think it would be preferable to be able to either use a DHCPV6 pool or to use manual configuration so that the resulting Interface Identifier is either bounded within a known range (tighter than 64 bits wide) or is a specific predictable address (like ::ABC/128 for all customer Gateways, etc.) or to have patterns like :AAAA: within an Identifier for all Edge Routers for easier "on sight" identification by SysAdmins...<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>However, after many days of reading, I cannot find any place that specifically details the method one would use to identify suitable ranges to choose from for a manually configured Interface ID or a pool of such IDs. Is it as simple as setting the 71st and 72nd bit and avoiding Anycast addresses?<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>RFC 5453 seems to be written to address this, but seems to have all the relevant detail missing...<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>What am I missing? Isn't this a concern for everyone?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:8.0pt'><img width=138 height=21 id="Picture_x0020_1" src="cid:image001.gif@01CBA02D.7FBA9D60" alt="Onramp Access"><br></span><b><span style='font-size:9.0pt;font-family:"Arial","sans-serif"'>chad kissinger </span></b><span style='font-size:9.0pt;font-family:"Arial","sans-serif"'> <b><span style='color:olive'>|</span> <span style='color:olive'>founder-vp |</span> <span style='color:olive'> </span></b><span style='color:olive'>onramp access, llc<b> <br>p: </b>512.322.9200</span><b> </b> <b><span style='color:olive'>|</span> </b> <b><span style='color:olive'>f:</span></b> <span style='color:olive'>512.476.2878<b> | </b> <u><a href="http://www.onr.com/" title="http://www.onr.com/ blocked::http://www.onr.com/"><span style='color:olive'>www.onr.com</span></a></u></span><u><br></u><b><span style='color:olive'>your internet operations</span></b><span style='color:olive'> | built | deployed | managed</span></span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>