- retronet-discuss - lists.osmocom.org

RetroNetCall on Mar 6, 2024: Telefax G4 protocol trace decoding

by Harald Welte

Dear Osmocom community, we're happy to announce the next incarnation of RetroNetCall[1], the retronetworking oriented spin-off of OsmoDevCall[2]. when: Mar 6, 2024 at 20:00 CET where: https://osmocom.org/RetroNetCall This time, @laforge will be presenting on Decoding of Telefax G4 protocol traces. We'll look into the ITU-specs of Group 4 Facsimile Service as well as at an actual B-channel protocol trace taken a few days ago. This meeting will have the following schedule: 20:00 meet + greet 20:10 presentation as outlined above 21:00 unstructured supplementary social event [3] Attendance is free of charge and open to anyone with an interest in Osmocom or open source cellular technologies. More information about RetroNetCall, including the schedule for further upcoming events can be found at https://osmocom.org/projects/retronetworking/wiki/RetroNetCall Looking forward to meeting you soon! Best regards, Harald [1] https://osmocom.org/projects/retronetworking/wiki/RetroNetCall [2] https://osmocom.org/projects/osmo-dev-con/wiki/OsmoDevCall [3] this is how we started to call the "unstructured" part of osmocom developer conferences in the past, basically where anyone can talk about anything, no formal schedule or structure. -- - Harald Welte <laforge(a)osmocom.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)

1 year, 4 months

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Software to emulate V.xxx modulations in PCM sample stream?

by Mychaela Falconia

Hello fellow retrotechnologists, I am looking for any existing software implementations of V.xxx modulations, those used by analog modems over POTS. Specifically, I am looking for software that can grok and generate streams of G.711 PCMU or PCMA samples, whether it be ISDN/T1/E1 or RTP, and thereby digitally grok and generate voiceband modem waveforms that can interoperate with a real V.xxx modem on the other end of the link. I was previously given an impression that some free sw offerings already exist that do what I just described, but I don't remember any specific names, nor do I recall ever being given any direct links. Would anyone here happen to know about such software? In my corner of USA I still have a real POTS landline, served out of a real 5ESS switch. That switch turns this POTS line into a 64 kbit/s G.711 PCMU sample stream, and using SIP trunk providers like BulkVS, I can access those PCMU sample streams (which were, once upon a time, telco-internal, unless you had ISDN which was super-rare in USA) when making and receiving calls on USA PSTN. I have a US Robotics Courier "V.Everything" modem connected to this POTS line, and my idea is to run some modem-emulating software on G.711 PCMU RTP streams on the SIP end - and aim for working interoperation between the real POTS modem on one end and a software emulation of modem waveforms in G.711 PCMU on the other end. In this lovely country of USA we also still have some public (govt-operated) service numbers where an analog modem answers when you call: https://www.nist.gov/pml/time-and-frequency-division/time-distribution/auto… I can call that NIST ACTS number from any voice phone and hear the answering modem screeching at me. Back when GSM/2G service of T-Mobile USA was in much better condition (as recently as 2018), I was able to make CSD calls to that ACTS number from my FreeCalypso GSM MS devices, and I used to get reliable connections, receiving the time code in ASCII each time - thus T-Mobile must have had a working IWF gateway that turned CSD into analog modem emulation, the exact same emulation I am currently after. That sweet CSD IWF seems to be broken now, but last night I tried a long-distance call from my POTS line (with my USR Courier modem) to that ACTS number in Colorado, and on the second try I got a successful connection at 9600 baud. Thus NIST ACTS itself appears to still be up and functional, and if I can find some working modem emulation software, I want to try connecting to ACTS with a modem-emulating G.711 PCMU RTP stream. Given that I operate my own Osmocom-based GSM network, my eventual goal is to build my own interworking gateway from GSM CSD to analog modem emulation, replicating the functionality that was wrongfully taken away by T-Mobile. However, before I bring GSM CSD into the mix, I seek to test the PSTN side of the equation by itself, just the leg between a software modem emulator in G.711 RTP and a real POTS modem on the other end. Toward that end, I would appreciate any pointers to suitable software implementations of V.xxx modulation standards. M~

1 year, 4 months

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Suggestion for documentation clarification Osmo-v5

by Jens Müller

Regarding https://osmocom.org/projects/retronetworking/wiki/Osmo-v5 I'm somewhat confused how this software interacts with other systems hardware-wise. Maybe you can add this to that documentation page for clarity? I understand this provides the network side of the E1 connection, but where does this run/how does it get connected to for example a Nokia EKSOS from a hardware perspective? Thanks for your work, Jens

1 year, 5 months

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RetroNetCall on Jan 3, 2024 (no presentation)

by Harald Welte

Dear Osmocom community, we're happy to announce the next incarnation of RetroNetCall[1], the retronetworking oriented spin-off of OsmoDevCall[2]. when: Jan 3, 2024 at 20:00 CET where: https://osmocom.org/RetroNetCall This time, there will not be any formal presentation. However, if people are interested, laforge can report on his most recent equipment acquisitions, primarily a vvariety of PDH (Siemens_FastLink) and SDH gear. Apart from that, we can chat about anything retro. This meeting will have the following schedule: 20:00 meet + greet 20:10 unstructured supplementary social event [3] Attendance is free of charge and open to anyone with an interest in retronetworking technologies. More information about RetroNetCall, including the schedule for further upcoming events can be found at https://osmocom.org/projects/retronetworking/wiki/RetroNetCall Looking forward to meeting you soon! Best regards, Harald [1] https://osmocom.org/projects/retronetworking/wiki/RetroNetCall [2] https://osmocom.org/projects/osmo-dev-con/wiki/OsmoDevCall [3] this is how we started to call the "unstructured" part of osmocom developer conferences in the past, basically where anyone can talk about anything, no formal schedule or structure. -- - Harald Welte <laforge(a)osmocom.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)

1 year, 6 months

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RetroNetCall on Dec 6, 2023: Tour of DIVF (yate + dahdi-trunkdev)

by Harald Welte

Dear Osmocom community, we're happy to announce the next incarnation of RetroNetCall[1], the retronetworking oriented spin-off of OsmoDevCall[2]. when: Dec 6, 2023 at 20:00 CET where: https://osmocom.org/RetroNetCall This time, @laforge will be presenting on A tour of DIVF, the OCTOI softswitch based on yate + dahdi-trunkdev We'll look into how subscriber E1 terminate in osmo-e1d + dahid-trunkdev, how that feeds into yate, how the routing/dialplan works, as well as the new SS7/ISUP interconnects to the two EWSD. This meeting will have the following schedule: 20:00 meet + greet 20:10 presentation as outlined above 21:00 unstructured supplementary social event [3] Attendance is free of charge and open to anyone with an interest in Osmocom or open source cellular technologies. More information about RetroNetCall, including the schedule for further upcoming events can be found at https://osmocom.org/projects/retronetworking/wiki/RetroNetCall Looking forward to meeting you soon! Best regards, Harald [1] https://osmocom.org/projects/retronetworking/wiki/RetroNetCall [2] https://osmocom.org/projects/osmo-dev-con/wiki/OsmoDevCall [3] this is how we started to call the "unstructured" part of osmocom developer conferences in the past, basically where anyone can talk about anything, no formal schedule or structure. -- - Harald Welte <laforge(a)osmocom.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)

1 year, 7 months

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RetroNetCall on Nov 1, 2023: EWSD Rescue + Bildtel 001

by Harald Welte

Dear Osmocom community, we're happy to announce the next incarnation of RetroNetCall[1], the retronetworking oriented spin-off of OsmoDevCall[2]. when: Nov 1, 2023 at 20:00 CET where: https://osmocom.org/RetroNetCall There won't be a formal presentation, but @lafforge will give an update on the "EWSD rescue" and his recent early research on the "BildTel 001" ISDN video phone. Attendance is free of charge and open to anyone with an interest in Osmocom or open source cellular technologies. More information about RetroNetCall, including the schedule for further upcoming events can be found at https://osmocom.org/projects/retronetworking/wiki/RetroNetCall Looking forward to meeting you soon! Best regards, Harald [1] https://osmocom.org/projects/retronetworking/wiki/RetroNetCall [2] https://osmocom.org/projects/osmo-dev-con/wiki/OsmoDevCall -- - Harald Welte <laforge(a)osmocom.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)

1 year, 8 months

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DEC VAX computer architecture

by Mychaela Falconia

Hello fellow retrotechnologists, This morning (my UTC-8:00 time zone) there was a USSE-only OsmoDevCall, but most of the topics discussed were more of RetroNetCall nature, which I don't mind at all - I am a retrocomputist first and foremost, and retronetworking goes quite well along with retrocomputing. Somehow the discussion touched the recent Vintage Computer Festival event that apparently happened somewhere in Germany (being on a different continent with no current passport and no travel budget, I am not exactly in the loop about European events), and it was mentioned that someone brought a VAX machine (running VMS) to the event, a model from the VAX 4000 family which I am not super-familiar with. (It's a quite late model as far as VAXen go, much newer than those I play with, but it appears to be an NVAX-based machine that is closer to a MicroVAX than a true VAX.) DEC VAX computer architecture is a topic very near and dear to my heart, as I worked on it very actively from late 1990s into early 2000s. Most of my work with this architecture has been with Q22-bus machines of MicroVAX II (MV2) and MicroVAX III (MV3) variety - to be pedantic, DEC never had an official model named MicroVAX III, but the informal designation MV3 is most fitting to describe the hw concoction that results if one takes an MV2 system in a BA123 cabinet and upgrades the CPU board from KA630 to KA650 or KA655. I still have several of these MV3 machines (some with KA650 and some with KA655) in my home machine room, and one of them I even keep running and still use for some everyday functions, mostly maintaining some notes in plain text files in vi and occasionally producing some TPS reports with troff suite. I run my own version of 1980s UNIX on these MicroVAXen, a derivative of 4.3BSD from UC Berkeley which I named 4.3BSD-Quasijarus back in late 1990s. The choice of name is certainly quite odd - I named it after a certain alien world (or maybe interdimensional pocket would be a better term) from Star Revenge sci-fi epic by Yury Petuhov - or maybe Petukhov ought to be "officially correct" transliteration, I dunno. The difficulty of transliterating Russian names into ASCII strings that can be pronounced by English-speaking tongues is a recurring problem, and the name of that alien world is no exception. In the original Russian, the name of that alien world or interdimensional pocket or whatever it should be called is \u041A\u0432\u0430\u0437\u0438\u044F\u0440\u0443\u0441 (yes, that's a Unicode string in C99 notation), and back in 1997 or so, when I was a fresh migrant from Russia to USA and spoke more Russian than English at home, I decided that Quasijarus was the best ASCIIfied rendition of that Russian sci-fi name - and so my MicroVAX UNIX OS was named. As this dear-to-me ancient computer architecture was brought up in this morning's ODC/RetroNetCall, I got into trying to explain the difference between a true VAX (such as VAX-11/780, VAX-11/750, VAX 8600, VAX 6000 series etc) and a much smaller MicroVAX - and then someone jokingly said something like "there is also Anti-VAX". How can I put it politely... I really, really don't like it when the name of my beloved vintage computer architecture has been hijacked to refer to a certain pharmaceutical product that is the antithesis of everything I stand for - hence I ask people to please differentiate between the two by using different spelling. The slang abbreviation for "vaccine" should NOT be "vax" - that's the name of the computer architecture - so please call that thing "vaxx" instead. Hence the abbreviations should be: pro-vaxer: someone in favor of DEC VAX computer architecture anti-vaxer: someone against this computer arch (all RISC lovers etc) pro-vaxxer: someone in favor of vaccination anti-vaxxer: someone against those poison injections By this terminology, I am very strongly pro-vax and equally strongly anti-vaxx. Any clearer now? :) It is also worth pointing out that the plural form of VAX (as in machines based on this CPU architecture) is VAXen, not *VAXes, just like the plural form of "ox" is oxen and not *oxes. (Asterisk prefix before a word form is standard linguistic notation for malformed words.) To the best of my knowledge (I never got to live through that history myself, but I once knew people who did), this plural form of VAX was established back in 1980s, back when this computer architecture was in active use, long before it transitioned to being a retrotechnology in the care of people like me. It certainly doesn't help that spoken pronunciation of "VAXen" in most English dialects sounds awfully close to that toxic pharma product, but oh well, what can we do - changing the name of a Holy retrotechnology from decades ago is NOT permissible for a maintainer and lorekeeper of said retrotech. At least it is very clearly distinct in ASCII-based written communication. Hasta la Victoria, Siempre, Mother Mychaela

1 year, 9 months

2
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RetroNetCall on Jul 5, 2023: Teletext

by Harald Welte

Dear Osmocom community, we're happy to announce the next incarnation of RetroNetCall[1], the retronetworking oriented spin-off of OsmoDevCall[2]. when: Jul 5, 2023 at 20:00 CEST where: https://osmocom.org/RetroNetCall This time, @casandro will be presenting on Teletext: A digital medium transcending a factor of 10e6 in technical progress NOTE: Teletext (covered here) is the service transporting textual information alongside TV broadcast signals. It is not to be confused with the completely unrelated Teletex (subject of previous RetroNetCall)! This meeting will have the following schedule: 20:00 meet + greet 20:10 presentation as outlined above 21:00 unstructured supplementary social event [3] Attendance is free of charge and open to anyone with an interest in Osmocom or open source cellular technologies. More information about RetroNetCall, including the schedule for further upcoming events can be found at https://osmocom.org/projects/retronetworking/wiki/RetroNetCall Looking forward to meeting you soon! Best regards, Harald [1] https://osmocom.org/projects/retronetworking/wiki/RetroNetCall [2] https://osmocom.org/projects/osmo-dev-con/wiki/OsmoDevCall [3] this is how we started to call the "unstructured" part of osmocom developer conferences in the past, basically where anyone can talk about anything, no formal schedule or structure. -- - Harald Welte <laforge(a)osmocom.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)

2 years

1
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RetroNetCall on Jun 7, 2023: Teletex

by Harald Welte

Dear Osmocom community, we're happy to announce the next incarnation of RetroNetCall[1], the retronetworking oriented spin-off of OsmoDevCall[2]. when: Jun 7, 2023 at 20:00 CEST where: https://osmocom.org/RetroNetCall This time, @laforge will be presenting on Teletex: The brief abandoned step between Telex and Telefax Everyone knows Telefax, and most people will have heard what Telex was. Few people are aware of the designated intermediate system Teletex. It was used like a "remote type writer", where formatted pages of (monospaced) text could be entered, transmitted and printed by a remote typewriter This meeting will have the following schedule: 20:00 meet + greet 20:10 presentation as outlined above 21:00 unstructured supplementary social event [3] Attendance is free of charge and open to anyone with an interest in Osmocom or open source cellular technologies. More information about RetroNetCall, including the schedule for further upcoming events can be found at https://osmocom.org/projects/retronetworking/wiki/RetroNetCall Looking forward to meeting you soon! Best regards, Harald [1] https://osmocom.org/projects/retronetworking/wiki/RetroNetCall [2] https://osmocom.org/projects/osmo-dev-con/wiki/OsmoDevCall [3] this is how we started to call the "unstructured" part of osmocom developer conferences in the past, basically where anyone can talk about anything, no formal schedule or structure. -- - Harald Welte <laforge(a)osmocom.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)

2 years, 1 month

1
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RetroNetCall on May 4, 2023: E1 - The analog side (part 1)

by Harald Welte

Dear Osmocom community, we're happy to announce the next incarnation of RetroNetCall[1], the retronetworking oriented spin-off of OsmoDevCall[2]. when: May 4, 2023 at 20:00 CEST where: https://osmocom.org/RetroNetCall This time, @tnt will be presenting on E1: The analog side (part 1) Many of us know E1 circuits from ISDN or GSM A-bis, and are familiar with the digital side of them. Building a related E1 interface mostly uses [still] available LIU (Line Interface Unit) integrated circuits. @tnt took it one step further and started to think along the lines of what if I had to do my own LIU analog circuit design? This meeting will have the following schedule: 20:00 meet + greet 20:10 presentation as outlined above 21:00 unstructured supplementary social event [3] Attendance is free of charge and open to anyone with an interest in Osmocom or open source cellular technologies. More information about RetroNetCall, including the schedule for further upcoming events can be found at https://osmocom.org/projects/retronetworking/wiki/RetroNetCall Looking forward to meeting you soon! Best regards, Harald [1] https://osmocom.org/projects/retronetworking/wiki/RetroNetCall [2] https://osmocom.org/projects/osmo-dev-con/wiki/OsmoDevCall [3] this is how we started to call the "unstructured" part of osmocom developer conferences in the past, basically where anyone can talk about anything, no formal schedule or structure. -- - Harald Welte <laforge(a)osmocom.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)

2 years, 2 months

2
1
0 0

2025

2024

2023

2022

retronet-discuss