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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif"">All,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif"">I am now starting to look at our infrastructure design for deploying strongswan as a production VPN headend.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif"">We are looking at support around 70,000 VPN users, with persistent VPN connections (Always on).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif"">Are there any good resources on scaling up / i.e. At what point does throwing tin and string at an instance stop being effective (we are thinking virtualized
 infrastructures here).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif"">Hardware resources are not really a constraint currently – we have access to a large amount of compute / can expand and build more, the same with our network
 infrastructure. It is very greenfield currently. <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif"">What about scale out? I have read some about clustering – but have come to the conclusion that this is quite difficult within strong swan, so maybe DNS load balancing
 with sticky session is more appropriate?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif"">What about load testing – I know about the strongswan load tester, but am interested in what realworld overhead is placed on the VPN headend by pushing traffic
 (and therefore encrypting it).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif"">Any ideas would be greatly appreciated.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif"">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"HP Simplified Light","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:9.0pt;font-family:"HP Simplified","sans-serif";color:black">Andy Paton -
</span></b><span style="font-size:9.0pt;font-family:"HP Simplified","sans-serif";color:#262626">Bsc. (Hons), MBCS</span><b><span style="font-size:9.0pt;font-family:"HP Simplified","sans-serif";color:black"><br>
</span></b><span style="font-size:9.0pt;font-family:"HP Simplified","sans-serif";color:#717172">Innovation Engineer<br>
<br>
<a href="mailto:andy.paton@hp.com"><span style="color:#717172">andy.paton@hp.com</span></a><br>
<br>
</span><a href="http://www.hp.com/"><span style="font-size:9.0pt;font-family:"HP Simplified","sans-serif";color:#717172;text-decoration:none"><img border="0" width="30" height="30" id="Picture_x0020_2" src="cid:image001.png@01CE93AB.D7BFE050" alt="HP"></span></a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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