LaForge's home page (Posts about retronetworking)https://laforge.gnumonks.org/blog/categories/retronetworking.atom2022-09-23T09:48:05ZHarald WelteNikolaDeployment of future community TDMoIP hubhttps://laforge.gnumonks.org/blog/20220919-octoi_hub_colocation_noris/2022-09-19T00:00:00+02:002022-09-19T00:00:00+02:00Harald Welte<p>I've mentioned some of my various <em>retronetworking</em> projects in some
past blog posts. One of those projects is <a class="reference external" href="https://osmocom.org/projects/octoi/wiki">Osmocom Community TDM over
IP (OCTOI)</a>. During the
past 5 or so months, we have been using a number of GPS-synchronized
open source <a class="reference external" href="https://osmocom.org/projects/e1-t1-adapter/wiki/IcE1usb">icE1usb</a>
interconnected by a <a class="reference external" href="https://osmocom.org/projects/octoi/wiki/Proposed_efficient_TDMoIP">new, efficient but strill transparent TDMoIP protocol</a> in order to run a distributed
TDM/PDH network. This network is currently only used to provide ISDN
services to retronetworking enthusiasts, but other uses like frame relay
have also been validated.</p>
<p>So far, the central <em>hub</em> of this OCTOI network has been operating in
the basement of my home, behind a consumer-grade DOCSIS cable modem
connection. Given that TDMoIP is relatively sensitive to packet loss,
this has been sub-optimal.</p>
<p>Luckily some of my old friends at <a class="reference external" href="https://noris.net">noris.net</a> have
agreed to host a new OCTOI hub free of charge in one of their
ultra-reliable co-location data centres. I'm already hosting some other
machines there for 20+ years, and noris.net is a good fit given that
they were - in their early days as an ISP - the driving force in the
early 90s behind one of the Linux kernel ISDN stracks called <a class="reference external" href="http://matthias.urlichs.de/bio/comp/">u-isdn</a>. So after many decades, ISDN
returns to them in a very different way.</p>
<p>Side note: In case you're curious, a reconstructed partial release
history of the u-isdn code can be found <a class="reference external" href="https://gitea.osmocom.org/retronetworking/u-isdn">on gitea.osmocom.org</a></p>
<p>But I digress. So today, there was the installation of this new OCTOI
hub setup. It has been prepared for several weeks in advance, and the
hub contains two circuit boards designed entirely only for this use
case. The most difficult challenge was the fact that this data centre
has no existing GPS RF distribution, and the roof is ~ 100m of CAT5
cable (no fiber!) away from the roof. So we faced the challenge of
passing the 1PPS (1 pulse per second) signal reliably through several
steps of lightning/over-voltage protection into the icE1usb whose
internal GPS-DO serves as a grandmaster clock for the TDM network.</p>
<p>The equipment deployed in this installation currently contains:</p>
<ul class="simple">
<li><p>a rather beefy Supermicro 2U server with EPYC 7113P CPU and 4x PCIe, two of which are populated with Digium TE820 cards resulting in a total of 16 E1 ports</p></li>
<li><p>an icE1usb with RS422 interface board connected via 100m RS422 to an
Ericsson GPS03 receiver. There's two layers of of over-voltage
protection on the RS422 (each with gas discharge tubes and TVS) and
two stages of over-voltage protection in the coaxial cable between
antenna and GPS receiver.</p></li>
<li><p>a <a class="reference external" href="https://osmocom.org/projects/retronetworking/wiki/Livingston_Portmaster_3">Livingston Portmaster3</a> RAS server</p></li>
<li><p>a <a class="reference external" href="https://osmocom.org/projects/retronetworking/wiki/Cisco_AS5400">Cisco AS5400</a> RAS server</p></li>
</ul>
<p>For more details, see <a class="reference external" href="https://osmocom.org/projects/octoi/wiki/Colocated_Hub">this wiki page</a> and <a class="reference external" href="https://osmocom.org/issues/5542">this ticket</a></p>
<p>Now that the physical deployment has been made, the next steps will be
to migrate all the TDMoIP links from the existing user base over to the
new hub. We hope the reliability and performance will be much better
than behind DOCSIS.</p>
<p>In any case, this new setup for sure has a lot of capacity to connect
many more more users to this network. At this point we can still only
offer E1 PRI interfaces. I expect that at some point during the coming
winter the project for remote TDMoIP BRI (S/T, S0-Bus) connectivity will
become available.</p>
<section id="acknowledgements">
<h2>Acknowledgements</h2>
<p>I'd like to thank anyone helping this effort, specifically
* Sylvain "tnt" Munaut for his work on the RS422 interface board (+ gateware/firmware)
* noris.net for sponsoring the co-location
* sysmocom for sponsoring the EPYC server hardware</p>
</section>Progress on the ITU-T V5 access network fronthttps://laforge.gnumonks.org/blog/20220909-wobcom-v5/2022-09-09T00:00:00+02:002022-09-09T00:00:00+02:00Harald Welte<p>Almost one year after my post <a class="reference external" href="https://laforge.gnumonks.org/blog/20170212-libosmo_sigtran/">regarding first steps towards a V5
implementation</a>, some friends
and I were finally able to visit <a class="reference external" href="https://www.wobcom.de/">Wobcom</a>, a
small German city carrier and pick up a lot of decommissioned
POTS/ISDN/PDH/SDH equipment, primarily V5 access networks.</p>
<p>This means that a number of retronetworking enthusiasts now have a
chance to play with Siemens Fastlink, Nokia EKSOS and DeTeWe ALIAN
access networks/multiplexers.</p>
<p>My primary interest is in Nokia EKSOS, which looks like an rather easy,
low-complexity target. As one of the first steps, I took PCB
photographs of the various modules/cards in the shelf, take note of the
main chip designations and started to search for the related
data sheets.</p>
<p>The results can be found in the Osmocom retronetworking wiki, with
<a class="reference external" href="https://osmocom.org/projects/retronetworking/wiki/Nokia_EKSOS">https://osmocom.org/projects/retronetworking/wiki/Nokia_EKSOS</a> being the main entry page, and sub-pages about</p>
<ul class="simple">
<li><p><a class="reference external" href="https://osmocom.org/projects/retronetworking/wiki/Nokia_EKSOS_Node_Control_Unit">Node Control Unit</a></p></li>
<li><p><a class="reference external" href="https://osmocom.org/projects/retronetworking/wiki/Nokia_EKSOS_BRI_UK0_Line_Card">16x BRI Uk0 Line Card</a></p></li>
<li><p><a class="reference external" href="https://osmocom.org/projects/retronetworking/wiki/Nokia_EKSOS_POTS_Line_Card">32x POTS Line Card</a></p></li>
<li><p><a class="reference external" href="https://osmocom.org/projects/retronetworking/wiki/Nokia_EKSOS_Line_Measurement_Unit">Line Measurement Unit</a></p></li>
<li><p><a class="reference external" href="https://osmocom.org/projects/retronetworking/wiki/Nokia_EKSOS_Shelf">Shelf</a></p></li>
</ul>
<p>In short: Unsurprisingly, a lot of Infineon analog and digital ICs for
the POTS and ISDN ports, as well as a number of Motorola M68k based
QUICC32 microprocessors and several unknown ASICs.</p>
<p>So with V5 hardware at my disposal, I've slowly re-started my efforts to
implement the LE (local exchange) side of the V5 protocol stack, with
the goal of eventually being able to interface those V5 AN with the
<a class="reference external" href="https://osmocom.org/projects/octoi/wiki">Osmocom Community TDM over IP network</a>. Once that is in place, we
should also be able to offer real ISDN Uk0 (BRI) and POTS lines at
retrocomputing events or hacker camps in the coming years.</p>Retronetworking at VCFB 2022https://laforge.gnumonks.org/blog/20220916-vcfb_2022_and_retronetworking/2022-09-09T00:00:00+02:002022-09-09T00:00:00+02:00Harald Welte<p>I'm happy to announce active participation at the <a class="reference external" href="https://vcfb.de/2022/">Vintage Computing
Festival Berlin 2022</a> in two ways:</p>
<ul class="simple">
<li><p>Running a <a class="reference external" href="https://vcfb.de/2022/ausstellungen.html">retronetworking exhibit on Modem and ISDN dial-up</a></p></li>
<li><p>Giving a <a class="reference external" href="https://vcfb.de/2022/vortraege_workshops.html">talk on the Osmocom Community TDMoIP netwokr</a></p></li>
</ul>
<p>The exhibit will be similar to the exhibit at the retrocomputing village
of the last CCC congress (36C3): A digital telephony network with ISDN
BRI and POTS lines providing services to a number of laptops with Modems
and ISDN terminal adapters.</p>
<p>We plan to demo the following things:
* analog modem and ISDN dial-up into BBSs
** text / ANSI interfaces via Telix, Telemate, Terminate
** RIPterm graphical interfaces
* analog modem and ISDN dial-up IP/internet
* ISDN video telephony</p>
<p>The client computers will be contemporary 486/Pentium machines wit DOS,
Windows 3.11 and OS/2.</p>