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<p class="MsoNormal">While looking through the PICS tests in the latest BPv7 OB draft, I was a bit confused about the handling of fragmentation in the light of the most recent discussions.<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:12.0pt;mso-fareast-language:EN-GB"><img width="638" height="570" style="width:6.65in;height:5.9416in" id="Picture_x0020_1" src="cid:image001.png@01DBE788.3FFDAE80"></span><span style="font-size:12.0pt;mso-ligatures:none;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Fragmentation itself is OPTIONAL in #31.<o:p></o:p></p>
<p class="MsoNormal">#32 is CONDITIONAL as it only makes sense if #31 is implemented.<o:p></o:p></p>
<p class="MsoNormal">#34 is OPTIONAL, so BPAs can choose to do on-path ADU reassembly.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">But #33 is MANDATORY, meaning EVERY BPA must support ADU reassembly.
<o:p></o:p></p>
<p class="MsoNormal">So even if we forbid fragmentation, and the feature at the source node is optional, all BPA that want to be compliant must still implement ADU reassembly logic and act upon it at the receiving end. This is quite a burden, increases attack
surface and just seems unnecessary for an optional feature and something which might be forbidden per policy in most deployments anyhow.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Wouldn’t it make sense to make this OPTIONAL as well since consensus now seems to be not to do fragmentation at all (at least in the short to mid term)?<o:p></o:p></p>
<p class="MsoNormal">One could also read the feature description as IF/WHEN doing reassembly (which itself is optional) it should then follow the rfc procedures, but then it would be CONDITIONAL, right?<o:p></o:p></p>
<p class="MsoNormal">Or maybe there is another way to read #33 that I missed…<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Kind regards and have a nice weekend,<o:p></o:p></p>
<p class="MsoNormal">Lars<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-GB">-- <o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-GB">Lars Baumgaertner<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-GB">Internal Research Fellow (OPS-GAE)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-GB">European Space Agency ESA/ESOC<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-GB">Robert-Bosch-Str. 5, D-64293 Darmstadt</span><span style="mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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