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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-size:11.0pt;font-family:"Aptos",serif'>Hi, Marc. A lot of the motivation for a “BP Sockets” API is that it could potentially minimize the cost of modifying IP applications that are already based on POSIX sockets I/O to use BP instead – you’d just modify a little bit of socket code and presto! your application now sends/receives bundles. Is the TAPS API lexically close enough to the POSIX sockets API to preserve this advantage? Or would the “AF_BUNDLE implementation delegating actual behavior to a userspace BPA implementation” that Brian references be a better way to accomplish that?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'>Scott<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;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><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> SIS-DTN <sis-dtn-bounces@mailman.ccsds.org> <b>On Behalf Of </b>Marc Blanchet via SIS-DTN<br><b>Sent:</b> Thursday, March 21, 2024 12:45 AM<br><b>To:</b> Brian J. Sipos <Brian.Sipos@jhuapl.edu><br><b>Cc:</b> Dr. Keith L Scott via SIS-DTN <sis-dtn@mailman.ccsds.org><br><b>Subject:</b> Re: [Sis-dtn] [EXT] Re: BP Sockets [was RE: IP networking within DTN-based protocol architectures]<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>Le 21 mars 2024 à 17:15, Sipos, Brian J. via SIS-DTN <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>> a écrit :<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>All,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>I meant to post this earlier to the mailing list instead of individual people.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Another thought related to kernel vs. userspace implementations of protocols are the pattern described in [3], specifically the design in Figure 3 where a kernel module implements the socket API for a new address family but delegates all behavior to a userspace daemon. This is akin to an AF_BUNDLE implementation delegating actual behavior to a userspace BPA implementation (as others have mentioned).<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Finally, there is also an IETF Transport Services (TAPS) <o:p></o:p></span></p></div></div></blockquote><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I said exactly that on this mailing list a while ago. One looking at defining a new Transport API should really look into TAPS. TAPS is a generic API for any transport: tcp, quic, udp, sctp, … It has generic transport semantics and a modern approach (all asynchronous).<o:p></o:p></p></div><p class=MsoNormal><br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>effort to create a socket API [4] that has similar logic and behavior to POSIX sockets but presumably not directly tied to kernel implementation so easier to adapt to new AFs and protocols. It looks preliminary, but could be an interesting avenue for prototyping these ideas without getting into kernel module stuff.<o:p></o:p></span></p></div></div></blockquote><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>It is more than preliminary. A well-known implementation is Apple, in production, in iOS and MacOSX: i.e. in your hands. I developed networking apps using it, and it is very modern. See: <a href="https://developer.apple.com/documentation/network">https://developer.apple.com/documentation/network</a> . TAPS is an IETF working group that has almost completed its work. See: <a href="https://datatracker.ietf.org/wg/taps/documents/">https://datatracker.ietf.org/wg/taps/documents/</a> (most documents are in or near IESG queue for publication). <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Regards, Marc.<o:p></o:p></p></div><p class=MsoNormal><br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>[3]<span class=apple-converted-space> </span><a href="https://www.usenix.org/system/files/conference/usenixsecurity18/sec18-o_neill.pdf">https://www.usenix.org/system/files/conference/usenixsecurity18/sec18-o_neill.pdf</a><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>[4]<span class=apple-converted-space> </span><a href="https://www.ietf.org/archive/id/draft-dreibholz-taps-neat-socketapi-14.html">https://www.ietf.org/archive/id/draft-dreibholz-taps-neat-socketapi-14.html</a><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='border:none;border-left:solid windowtext 1.5pt;padding:0in 0in 0in 4.0pt;border-color:currentcolor currentcolor currentcolor blue;border-image: none'><div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0in 0in 0in;border-color:currentcolor currentcolor;border-image: none'><div><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Sipos, Brian J.<span class=apple-converted-space> </span><br><b>Sent:</b><span class=apple-converted-space> </span>Wednesday, March 20, 2024 1:09 AM<br><b>To:</b><span class=apple-converted-space> </span>'<a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>' <<a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>>;<span class=apple-converted-space> </span><a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a>;<span class=apple-converted-space> </span><a href="mailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int</a>;<span class=apple-converted-space> </span><a href="mailto:vint@google.com">vint@google.com</a><br><b>Subject:</b><span class=apple-converted-space> </span>RE: [EXT] Re: [Sis-dtn] BP Sockets [was RE: IP networking within DTN-based protocol architectures]<o:p></o:p></span></p></div></div></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>All,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>I agree that the POSIX socket interface provides all of the needed mechanisms do the job of datagram sending/receiving. One thing that I think is an important aspect of BP agent--application interface is the ability for the application to influence sourced metadata and have visibility into delivered metadata (e.g. in addition to the primary block EIDs, things like the Lifetime value or Hop Count values). Since there is a similar need in IP land there are mechanisms like IP_PKTINFO and “control data” like IP_TOS / IP_RECVTOS or IP_TTL / IP_RECVTTL with recvmsg [1].<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>All of that is when used with SOCK_DGRAM -type sockets sending/receiving ADUs as the msg data. A separate interface with SOCK_RAW -type sockets could have the entire encoded bundle present as the msg data. Similar to using (AF_INET, SOCK_RAW) sockets this allows full visibility into header contents but puts a quite large burden on the application to properly handle and process that data.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>On the other hand, implementations of recent transports like QUIC have specifically opted out of in-kernel processing with an associated POSIX socket API. Just something to consider from another recent transport protocol development. Putting implementation into kernel space is quite a large hurdle to clear. But also nothing says you cannot implement a ‘prototype’ userspace API modeled after the sockets API like `bp_socket()` `bp_sendmsg()`, etc.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>[1]<span class=apple-converted-space> </span><a href="https://man7.org/linux/man-pages/man7/ip.7.html">https://man7.org/linux/man-pages/man7/ip.7.html</a><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>[2]<span class=apple-converted-space> </span><a href="https://stackoverflow.com/questions/16165542/is-it-possible-to-read-the-ttl-ip-header-field-when-receiving-udp-packets">https://stackoverflow.com/questions/16165542/is-it-possible-to-read-the-ttl-ip-header-field-when-receiving-udp-packets</a><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='border:none;border-left:solid windowtext 1.5pt;padding:0in 0in 0in 4.0pt;border-color:currentcolor currentcolor currentcolor blue;border-image: none'><div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0in 0in 0in;border-color:currentcolor currentcolor;border-image: none'><div><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a>><span class=apple-converted-space> </span><b>On Behalf Of<span class=apple-converted-space> </span></b>sburleig.sb--- via SIS-DTN<br><b>Sent:</b><span class=apple-converted-space> </span>Monday, March 11, 2024 10:22 AM<br><b>To:</b><span class=apple-converted-space> </span><a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a>;<span class=apple-converted-space> </span><a href="mailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int</a>;<span class=apple-converted-space> </span><a href="mailto:vint@google.com">vint@google.com</a><br><b>Cc:</b><span class=apple-converted-space> </span><a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b><span class=apple-converted-space> </span>[EXT] Re: [Sis-dtn] BP Sockets [was RE: IP networking within DTN-based protocol architectures]<o:p></o:p></span></p></div></div></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><div id=APLWarningText><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 align=left><tr><td width="100%" style='width:100.0%;background:#E0E0E0;padding:0in 0in 0in 0in'><div><p class=MsoNormal style='mso-element:frame;mso-element-frame-hspace:2.25pt;mso-element-wrap:around;mso-element-anchor-vertical:paragraph;mso-element-anchor-horizontal:column;mso-height-rule:exactly'><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:red'>APL external email warning:<span class=apple-converted-space> </span></span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:black'>Verify sender<span class=apple-converted-space> </span><a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a>before clicking links or attachments</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></td></tr></table><p><span style='font-size:10.5pt;font-family:"Helvetica",sans-serif'> <o:p></o:p></span></p></div></div><div><p class=MsoNormal><span style='font-size:11.0pt;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.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'>Scott</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0in 0in 0in;border-color:currentcolor currentcolor;border-image: none'><div><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a><span class=apple-converted-space> </span><<a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a>><span class=apple-converted-space> </span><br><b>Sent:</b><span class=apple-converted-space> </span>Monday, March 11, 2024 3:48 AM<br><b>To:</b><span class=apple-converted-space> </span><a href="mailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int</a>;<span class=apple-converted-space> </span><a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>;<span class=apple-converted-space> </span><a href="mailto:vint@google.com">vint@google.com</a><br><b>Cc:</b><span class=apple-converted-space> </span><a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b><span class=apple-converted-space> </span>RE: BP Sockets [was RE: [Sis-dtn] IP networking within DTN-based protocol architectures]<o:p></o:p></span></p></div></div></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Hi,</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>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.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Thanks,</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Jeremy</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0in 0in 0in;border-color:currentcolor currentcolor;border-image: none'><div><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Felix Flentge <<a href="mailto:Felix.Flentge@esa.int">Felix.Flentge@esa.int</a>><span class=apple-converted-space> </span><br><b>Sent:</b><span class=apple-converted-space> </span>Montag, 11. März 2024 11:46<br><b>To:</b><span class=apple-converted-space> </span><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>>;<span class=apple-converted-space> </span><a href="mailto:vint@google.com">vint@google.com</a><br><b>Cc:</b><span class=apple-converted-space> </span><a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b><span class=apple-converted-space> </span>BP Sockets [was RE: [Sis-dtn] IP networking within DTN-based protocol architectures]<o:p></o:p></span></p></div></div></div><div><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Hi,</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>I like the idea but isn’t this already covered (partially) by the CCSSDS BP service interface, eg:</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=DE style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=DE style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Bind – register EID in passive state</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Listen –<span class=apple-converted-space> </span></span><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>register EID in active state</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Connect – sets a default destination for future send.request</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Send – send.request<span class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Recv – poll.request</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Regards,</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Felix</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0in 0in 0in;border-color:currentcolor currentcolor;border-image: none'><div style='margin-left:.5in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org">sis-dtn-bounces@mailman.ccsds.org</a>><span class=apple-converted-space> </span><b>On Behalf Of<span class=apple-converted-space> </span></b>sburleig.sb--- via SIS-DTN<br><b>Sent:</b><span class=apple-converted-space> </span>Saturday, March 9, 2024 6:56 PM<br><b>To:</b><span class=apple-converted-space> </span><a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a>;<span class=apple-converted-space> </span><a href="mailto:vint@google.com">vint@google.com</a><br><b>Cc:</b><span class=apple-converted-space> </span><a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b><span class=apple-converted-space> </span>Re: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></span></p></div></div></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;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.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'>Scott</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0in 0in 0in;border-color:currentcolor currentcolor;border-image: none'><div style='margin-left:.5in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a><span class=apple-converted-space> </span><<a href="mailto:Jeremy.Mayer@dlr.de">Jeremy.Mayer@dlr.de</a>><span class=apple-converted-space> </span><br><b>Sent:</b><span class=apple-converted-space> </span>Saturday, March 9, 2024 8:01 AM<br><b>To:</b><span class=apple-converted-space> </span><a href="mailto:vint@google.com">vint@google.com</a>;<span class=apple-converted-space> </span><a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a><br><b>Cc:</b><span class=apple-converted-space> </span><a href="mailto:Tomaso.deCola@dlr.de">Tomaso.deCola@dlr.de</a>;<span class=apple-converted-space> </span><a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b><span class=apple-converted-space> </span>RE: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></span></p></div></div></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Hi,</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>That’s a fair point. Generally, I’d say that BP-POSIX could work with the following:</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Bind – works: sets source EID.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Listen – works; sets source EID and opens reception.<span class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Connect – UDP style, sets default destination address.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Send – only valid for connected bundlesocks.<span class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Sendto/sendmsg – works.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Recv – works.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Recvfrom/recvmsg – works, probably should support “wildcard” EIDs, at least for services.<span class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Getaddrinfo and friends – not required</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:1.0in'><p class=MsoNormal style='text-indent:-.25in'><span lang=EN-GB style='font-size:11.0pt;font-family:Symbol'>·</span><span lang=EN-GB style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Select – Works, highly implementation dependent.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>BSD sockets really do work for everything!</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Thanks,</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Jeremy</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0in 0in 0in;border-color:currentcolor currentcolor;border-image: none'><div style='margin-left:.5in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Vint Cerf <<a href="mailto:vint@google.com">vint@google.com</a>><span class=apple-converted-space> </span><br><b>Sent:</b><span class=apple-converted-space> </span>Samstag, 9. März 2024 16:51<br><b>To:</b><span class=apple-converted-space> </span>Scott Burleigh <<a href="mailto:sburleig.sb@gmail.com">sburleig.sb@gmail.com</a>><br><b>Cc:</b><span class=apple-converted-space> </span>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><span class=apple-converted-space> </span>Re: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></span></p></div></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Yes generally speaking</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>On Sat, Mar 9, 2024, 10:43 <</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><a href="mailto:sburleig.sb@gmail.com"><span lang=DE>sburleig.sb@gmail.com</span></a></span><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>> wrote:</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></div><blockquote style='border:none;border-left:solid windowtext 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt;border-color:currentcolor currentcolor currentcolor rgb(204, 204, 204);border-image: none'><div><div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;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><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'>Scott</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Aptos",serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0in 0in 0in;border-color:currentcolor currentcolor;border-image: none'><div style='margin-left:.5in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org" target="_blank">sis-dtn-bounces@mailman.ccsds.org</a>><span class=apple-converted-space> </span><b>On Behalf Of<span class=apple-converted-space> </span></b>Jeremy Mayer via SIS-DTN<br><b>Sent:</b><span class=apple-converted-space> </span>Saturday, March 9, 2024 12:35 AM<br><b>To:</b><span class=apple-converted-space> </span><a href="mailto:vint@google.com" target="_blank">vint@google.com</a>;<span class=apple-converted-space> </span><a href="mailto:Tomaso.deCola@dlr.de" target="_blank">Tomaso.deCola@dlr.de</a><br><b>Cc:</b><span class=apple-converted-space> </span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b><span class=apple-converted-space> </span>Re: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></span></p></div></div></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Hi,</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>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><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><p class=m-2940071027920571956msolistparagraph style='margin-left:1.0in;text-indent:-.25in'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>A.</span><span style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>The assumption that relatively low-latency and bidirectional communication is available.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p><p class=m-2940071027920571956msolistparagraph style='margin-left:1.0in;text-indent:-.25in'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>B.</span><span style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>The layering of stream and message-based semantics.</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>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 class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>+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><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Thanks,</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Jeremy</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='border:none;border-top:solid windowtext 1.0pt;padding:3.0pt 0in 0in 0in;border-color:currentcolor currentcolor;border-image: none'><div style='margin-left:.5in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span class=apple-converted-space><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>SIS-DTN <<a href="mailto:sis-dtn-bounces@mailman.ccsds.org" target="_blank">sis-dtn-bounces@mailman.ccsds.org</a>><span class=apple-converted-space> </span><b>On Behalf Of<span class=apple-converted-space> </span></b>Vint Cerf via SIS-DTN<br><b>Sent:</b><span class=apple-converted-space> </span>Freitag, 8. März 2024 12:31<br><b>To:</b><span class=apple-converted-space> </span>de Cola, Tomaso <<a href="mailto:Tomaso.deCola@dlr.de" target="_blank">Tomaso.deCola@dlr.de</a>><br><b>Cc:</b><span class=apple-converted-space> </span><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank">sis-dtn@mailman.ccsds.org</a><br><b>Subject:</b><span class=apple-converted-space> </span>Re: [Sis-dtn] IP networking within DTN-based protocol architectures<o:p></o:p></span></p></div></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>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><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>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><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>v</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></div></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>On Fri, Mar 8, 2024 at 4:24 AM Tomaso de Cola via SIS-DTN <</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><a href="mailto:sis-dtn@mailman.ccsds.org" target="_blank"><span lang=DE>sis-dtn@mailman.ccsds.org</span></a></span><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>> wrote:</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div></div><blockquote style='border:none;border-left:solid windowtext 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt;border-color:currentcolor currentcolor currentcolor rgb(204, 204, 204);border-image: none'><div><div><div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Dear All,</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>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).<span class=apple-converted-space> </span><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>The link to that presentation is as follows:<o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><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></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>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></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>As discussed yesterday, key points to clarify/agree are:<o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><p class=m-2940071027920571956m128766250028595583msolistparagraph style='margin-left:1.0in;text-indent:-.25in'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>1.</span><span style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Is the proposal sound and meaningful to be addressed?<o:p></o:p></span></p><p class=m-2940071027920571956m128766250028595583msolistparagraph style='margin-left:1.0in;text-indent:-.25in'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>2.</span><span style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>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></span></p><p class=m-2940071027920571956m128766250028595583msolistparagraph style='margin-left:1.0in;text-indent:-.25in'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>3.</span><span style='font-size:7.0pt'> <span class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>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></span></p><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Thank you for sharing comments/objections/suggestions.<o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Have a nice weekend,<o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Tomaso<o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> <o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>————————————————————————</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><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 class=apple-converted-space><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'> </span></span><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>(DLR)</span><span lang=DE style='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='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 style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p></o:p></span></p></div><div style='margin-left:.5in'><p class=MsoNormal><b><span lang=IT style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>Tomaso de Cola, Ph.D.</span></b><span class=apple-converted-space><span lang=IT style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> </span></span><span lang=IT style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>|<span class=apple-converted-space> </span></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<span class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><a href="tel:+49%208153%20282156" target="_blank"><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif'>+49 8153 28-2156</span></a></span><span class=apple-converted-space><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'> </span></span><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>| Telefax <span class=apple-converted-space> </span></span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><a href="tel:+49%208153%20282844" target="_blank"><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif'>+49 8153 28-2844</span></a></span><span class=apple-converted-space><span lang=DE style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'> 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