<html><head><meta http-equiv="Content-Type" content="text/html charset=windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div>This is complicate. In what scenarios do we need to use “up to a level” as an NDN name component?</div><div><br></div>Can we treat ‘.’ and ‘..’ as is without the special meaning of “this level” and “up to a level”? I’m also fine with treating them as illegal name components. <div><br></div><div>Beichuan<br><div><br><div><div>On Aug 10, 2014, at 9:35 PM, Junxiao Shi <<a href="mailto:shijunxiao@email.arizona.edu">shijunxiao@email.arizona.edu</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div dir="ltr">Dear folks<div><br></div><div>I looked at RFC3986 again.</div><div><br></div><div>Section 6.2.2.3. Path Segment Normalization states:<br></div><blockquote style="margin:0 0 0 40px;border:none;padding:0px">
<div>The complete path segments "." and ".." are intended only for use within relative references (Section 4.1) and are removed as part of the reference resolution process (Section 5.2). However, some deployed implementations incorrectly assume that reference resolution is not necessary when the reference is already a URI and thus fail to remove dot-segments when they occur in non-relative paths.</div>
</blockquote><div>This implies that "." and ".." are both permitted in absolute URIs.</div><div>The exact rules are defines in Section 5.2.</div><div><br></div><div>Therefore, these ndn: URIs are all equivalent:</div>
<div><ul><li>/A/B/C</li><li>ndn:/A/B/C</li><li><a href="ndn:///A/B/C">ndn:///A/B/C</a></li><li><a href="ndn://authority/A/B/C">ndn://authority/A/B/C</a></li><li>/A/./B/C</li><li>/A/D/../B/C</li><li>/../A/B/C</li><li>/./A/B/C</li></ul></div><div><br></div><div>Yours, Junxiao<div class="gmail_extra">
<br><div class="gmail_quote">On Wed, Aug 6, 2014 at 9:49 AM, Thompson, Jeff <span dir="ltr"><<a href="mailto:jefft0@remap.ucla.edu" target="_blank">jefft0@remap.ucla.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
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<div>Hi Junxiao,</div>
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</div>
<div>Using your example of the URL for RFC3986, the following link works:</div>
<div><a href="http://tools.ietf.org/html/rfc3986#section-3.3" target="_blank">http://tools.ietf.org/html/rfcblahblahblah/../rfc3986#section-3.3</a></div>
<div><br>
</div>
<div>So ".." is illegal in a URI, but legal in a URL? Maybe the support for .. In a URL is non-standard?</div>
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</div>
<div>- Jeff T</div>
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<div style="font-family: Calibri; font-size: 11pt; text-align: left; border-width: 1pt medium medium; border-style: solid none none; padding: 3pt 0in 0in; border-top-color: rgb(181, 196, 223);">
<span style="font-weight:bold">From: </span>Junxiao Shi <<a href="mailto:shijunxiao@email.arizona.edu" target="_blank">shijunxiao@email.arizona.edu</a>><br>
<span style="font-weight:bold">Date: </span>Tuesday, August 5, 2014 9:27 AM<br>
<span style="font-weight:bold">To: </span>Jeff Thompson <<a href="mailto:jefft0@remap.ucla.edu" target="_blank">jefft0@remap.ucla.edu</a>><br>
<span style="font-weight:bold">Cc: </span>nfd-dev <<a href="mailto:nfd-dev@lists.cs.ucla.edu" target="_blank">nfd-dev@lists.cs.ucla.edu</a>><br>
<span style="font-weight:bold">Subject: </span>Re: [Nfd-dev] How to treat ".." in an NDN URI?<br>
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<div dir="ltr">Hi JeffT
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<div>TLV spec cites RFC3986 for URI syntax. The processing of ".." doesn't need to be mentioned in TLV spec because it's inherited from RFC3986.</div>
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<div><a href="http://tools.ietf.org/html/rfc3986#section-3.3" target="_blank">RFC3986</a> says:</div>
<blockquote style="margin:0px 0px 0px 40px;border:none;padding:0px">
<div>The path segments "." and "..", also known as dot-segments, are defined for relative reference within the path name hierarchy. They are intended for use at the beginning of a relative-path reference to indicate relative position within the hierarchical
tree of names.</div>
</blockquote>
<div>Therefore, if ".." appears within an absolute ndn URI, the entire URI is invalid and should raise an error.</div>
<div><br>
</div>
<div>
<div class="gmail_extra">Yours, Junxiao<br></div></div></div></div></div></div></div></span></div></blockquote></div></div></div></div>
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