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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Hey,<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Alex mentioned long ago the idea\option to add an ICAP service as an external_acl helper.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>I want to highlight my understanding of couple things about the subject.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Currently external_acl helpers are required to "decide" on an action based only on couple basic parts of the request.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>It's not bad or wrong but ICAP can extend squid helpers assistance.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>It can extend the decision to the brief request and response details.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Alex mentioned at the time that ICAP services implements ACLs but in a form which the interface maybe was not designed for.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>I think that the ICAP services interface usage might be used a bit "off" to what it was designed for but it seems OK to me for many cases.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Also any ICAP implementation requires a more deep understanding of HTTP in general which has it’s own pros and cons.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>The main benefit of an ICAP service as I see it is that it's not bound to squid or c++ compared to eCAP.<br>Means I like ICAP better and maybe since I have better luck with it.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>And to the actual implementation idea:<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>There are couple options on how an ICAP service should respond.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>I think that "OK" or "ERR" are good but a "DUNNO" ie use default action could be used.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>I hope that you have comments to write about the subject.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Will it be good to add ICAP based external acl interfaces?<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Maybe it's too complex?<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Are there any benefits to external_acl helpers over ICAP services?<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Thanks,<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Eliezer<o:p></o:p></p><p class=MsoNormal dir=RTL><span lang=HE style='font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><span dir=LTR></span><span dir=LTR></span><span style='font-family:"Arial Rounded MT Bold","sans-serif"'><span dir=LTR></span><span dir=LTR></span>----<o:p></o:p></span></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><span style='font-family:"Arial Rounded MT Bold","sans-serif"'><a href="http://ngtech.co.il/lmgtfy/">Eliezer Croitoru</a><br>Linux System Administrator<br>Mobile: +972-5-28704261<br>Email: eliezer@ngtech.co.il<o:p></o:p></span></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><img border=0 width=183 height=69 id="Picture_x0020_1" src="cid:image001.png@01D1CA52.18ECDBC0"><o:p></o:p></p><p class=MsoNormal dir=RTL><span dir=LTR><o:p> </o:p></span></p></div></body></html>