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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='font-family:"Aptos",serif'>Right, the service interface in the CCSDS BP specification -- like all service specifications -- is abstract; it defines the properties of a BP API for the purpose of explaining the required behavior of a Bundle Protocol Agent. Any number of existing and future BP implementations with very different APIs can be wholly conformant to that specification. But a BP sockets specification would enable any application that currently communicates over POSIX (BSD) sockets to use BP instead of UDP without extensive code changes; the syntax is already in place. That’s the compelling advantage of the idea.<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Aptos",serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Aptos",serif'>Scott<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Aptos",serif'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From:</b> Jeremy.Mayer@dlr.de <Jeremy.Mayer@dlr.de> <br><b>Sent:</b> Monday, March 11, 2024 3:48 AM<br><b>To:</b> Felix.Flentge@esa.int; sburleig.sb@gmail.com; vint@google.com<br><b>Cc:</b> sis-dtn@mailman.ccsds.org<br><b>Subject:</b> RE: BP Sockets [was RE: [Sis-dtn] IP networking within DTN-based protocol architectures]<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-GB>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB>In the abstract, I’d say so, but (let’s be honest) many developers tend to ignore the abstract notion of the service interface and prefer to have a tangible set of API operations.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB>Jeremy<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From:</b> Felix Flentge <<a href="mailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int</a>> <br><b>Sent:</b> Montag, 11. März 2024 11:46<br><b>To:</b> <a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>; Mayer, Jeremy <<a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a>>; <a href="mailto:vint@google.com">vint@google.com</a><br><b>Cc:</b> <a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b> BP Sockets [was RE: [Sis-dtn] IP networking within DTN-based protocol architectures]<o:p></o:p></p></div></div><p class=MsoNormal><span lang=DE><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>I like the idea but isn’t this already covered (partially) by the CCSSDS BP service interface, eg:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=DE style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=DE>Bind – register EID in passive state<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Listen – </span><span lang=DE>register EID in active state</span><span lang=EN-GB><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Connect – sets a default destination for future send.request<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Send – send.request <o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Recv – poll.request<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><div><p class=MsoNormal><span lang=EN-GB>Regards,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB>Felix<o:p></o:p></span></p></div><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='margin-left:.5in'><b>From:</b> SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a>> <b>On Behalf Of </b>sburleig.sb--- via SIS-DTN<br><b>Sent:</b> Saturday, March 9, 2024 6:56 PM<br><b>To:</b> <a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a>; <a href="mailto:vint@google.com">vint@google.com</a><br><b>Cc:</b> <a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b> Re: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></p></div></div><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span style='font-family:"Aptos",serif'>Thanks for that analysis, Jeremy. We’ve been talking about at least since STINT several years ago, and I really think it’s an idea whose time has come.<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span style='font-family:"Aptos",serif'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span style='font-family:"Aptos",serif'>Scott<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span style='font-family:"Aptos",serif'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='margin-left:.5in'><b>From:</b> <a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a> <<a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a>> <br><b>Sent:</b> Saturday, March 9, 2024 8:01 AM<br><b>To:</b> <a href="mailto:vint@google.com">vint@google.com</a>; <a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a><br><b>Cc:</b> <a href="mailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de</a>; <a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b> RE: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></p></div></div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB>Hi,<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB>That’s a fair point. Generally, I’d say that BP-POSIX could work with the following:<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Bind – works: sets source EID.<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Listen – works; sets source EID and opens reception. <o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Connect – UDP style, sets default destination address.<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Send – only valid for connected bundlesocks. <o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Sendto/sendmsg – works.<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Recv – works.<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Recvfrom/recvmsg – works, probably should support “wildcard” EIDs, at least for services. <o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Getaddrinfo and friends – not required<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span lang=EN-GB style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-GB>Select – Works, highly implementation dependent.<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB>BSD sockets really do work for everything!<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB>Thanks,<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB>Jeremy<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span lang=EN-GB><o:p> </o:p></span></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='margin-left:.5in'><b>From:</b> Vint Cerf <<a href="mailto:vint@google.com">vint@google.com</a>> <br><b>Sent:</b> Samstag, 9. März 2024 16:51<br><b>To:</b> Scott Burleigh <<a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>><br><b>Cc:</b> Mayer, Jeremy <<a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a>>; de Cola, Tomaso <<a href="mailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de</a>>; Dr. Keith L Scott via SIS-DTN <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>><br><b>Subject:</b> Re: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'><span lang=DE><o:p> </o:p></span></p><div><p class=MsoNormal style='margin-left:.5in'><span lang=DE>Yes generally speaking<o:p></o:p></span></p></div><p class=MsoNormal style='margin-left:.5in'><span lang=DE><o:p> </o:p></span></p><div><div><p class=MsoNormal style='margin-left:.5in'><span lang=DE>On Sat, Mar 9, 2024, 10:43 <<a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>> wrote:<o:p></o:p></span></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span style='font-family:"Aptos",serif'>I think we get closer to BSD/POSIX if we use UDP as a model. The attenuated UDP notion of connect() would work for BP, I think.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span style='font-family:"Aptos",serif'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span style='font-family:"Aptos",serif'>Scott</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span style='font-family:"Aptos",serif'> </span><o:p></o:p></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><b>From:</b> SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org" target="_blank">sis-dtn-bounces@mailman.ccsds.org</a>> <b>On Behalf Of </b>Jeremy Mayer via SIS-DTN<br><b>Sent:</b> Saturday, March 9, 2024 12:35 AM<br><b>To:</b> <a href="mailto:vint@google.com" target="_blank">vint@google.com</a>; <a href="mailto:Tomaso.deCola@dlr.de" target="_blank">Tomaso.deCola@dlr.de</a><br><b>Cc:</b> <a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b> Re: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB>Hi,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB>I’m tempted to agree. I’ve seen limited utility in IP->BP encap, as (other than some unidirectional UDP-based applications), the assumptions made in IP networks (especially TCP) do not scale well to DTN environments. The two largest issues I see are:</span><o:p></o:p></p><p class=m-2940071027920571956msolistparagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l1 level1 lfo4'><![if !supportLists]><span style='mso-list:Ignore'>A.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span lang=EN-GB>The assumption that relatively low-latency and bidirectional communication is available.</span><o:p></o:p></p><p class=m-2940071027920571956msolistparagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l1 level1 lfo4'><![if !supportLists]><span style='mso-list:Ignore'>B.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span lang=EN-GB>The layering of stream and message-based semantics.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB>Almost every TCP-ish application which I’ve seen run over BP winds up with exceptionally low performance, unless some sort of PEP is integrated, which adds complexity, failure points, and fragility. </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB>+1 for the notion of a standard API though, with the additional caveat that we should standardize nomenclature across implementations. We could likely reuse about 80% of the BSD/POSIX interface for BP, with the notable exception of connect.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB>Thanks,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB>Jeremy</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=EN-GB> </span><o:p></o:p></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><b>From:</b> SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org" target="_blank">sis-dtn-bounces@mailman.ccsds.org</a>> <b>On Behalf Of </b>Vint Cerf via SIS-DTN<br><b>Sent:</b> Freitag, 8. März 2024 12:31<br><b>To:</b> de Cola, Tomaso <<a href="mailto:Tomaso.deCola@dlr.de" target="_blank">Tomaso.deCola@dlr.de</a>><br><b>Cc:</b> <a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b> Re: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE> </span><o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE>The more I think about this, the less I like trying to manage off-Earth IP networks remotely. I think I would much rather see native applications running over BP. In any case we need to develop standard APIs for BP, such as the Sockets interface for Linux/Unix/Posix. </span><o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE> </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE>We do need to figure out how IP-based and BP-based applications interwork. What do Domain Names mean in the BP context for example. </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE> </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE>v</span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE> </span><o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE> </span><o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE>On Fri, Mar 8, 2024 at 4:24 AM Tomaso de Cola via SIS-DTN <<a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a>> wrote:</span><o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt'><div><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE>Dear All,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>as mentioned yesterday during our DTN weekly, during the past Fall meeting a presentation was given by University of Nanjing with the support of Chinese agency about IP-networking within DTN-based protocol stacks, especially for planetary network segments (i.e. what is often referred to as IP-islands). <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>The link to that presentation is as follows:<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><a href="https://cwe.ccsds.org/sis/docs/SIS-DTN/Meeting%20Materials/2023/Fall%202023%20SIS-DTN/Possible%20BOF%20Discussion.pptx?d=w44d31f0b3be649e4bf24ec4ae50479a1" target="_blank">https://cwe.ccsds.org/sis/docs/SIS-DTN/Meeting%20Materials/2023/Fall%202023%20SIS-DTN/Possible%20BOF%20Discussion.pptx?d=w44d31f0b3be649e4bf24ec4ae50479a1</a><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>The proposal made there was for a BOF (i.e. towards a WG formation), which I see however too premature. On the contrary, I’d be more in favour for a SIG (Special Interest Group), happening outside the DTN WG.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>As discussed yesterday, key points to clarify/agree are:<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=m-2940071027920571956m128766250028595583msolistparagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l0 level1 lfo6'><![if !supportLists]><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>Is the proposal sound and meaningful to be addressed?<o:p></o:p></p><p class=m-2940071027920571956m128766250028595583msolistparagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l0 level1 lfo6'><![if !supportLists]><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>Is appropriate for the SIS area or should be better addressed at architectural level in SEA (maybe it can be even a cross-area initiative)?<o:p></o:p></p><p class=m-2940071027920571956m128766250028595583msolistparagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l0 level1 lfo6'><![if !supportLists]><span style='mso-list:Ignore'>3.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>In the case of SIS, is there significant support to start this? In other words, which agencies have interest in contributing to this activity?<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>Thank you for sharing comments/objections/suggestions.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>Have a nice weekend,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'>Tomaso<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>————————————————————————</span><span lang=DE style='font-size:12.0pt;font-family:"Times New Roman",serif'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><b><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>Deutsches Zentrum für Luft- und Raumfahrt</span></b><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'> (DLR)</span><span lang=DE style='font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D'> <br></span><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>German Aerospace Center</span><span lang=DE style='font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D'> <br></span><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>Institute of Communications and Navigation | Satellite Networks | Oberpfaffenhofen | 82234 Wessling | Germany</span><span lang=DE style='font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in'><b><span lang=IT style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>Tomaso de Cola, Ph.D.</span></b><span lang=IT style='color:#1F497D'> | </span><b><span lang=IT style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>Integrated Satellite Systems (INS) Team Leader<br></span></b><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>Telefon <a href="tel:+49%208153%20282156" target="_blank">+49 8153 28-2156</a> | Telefax <a href="tel:+49%208153%20282844" target="_blank">+49 8153 28-2844</a> |</span><span lang=DE 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