The Serial Port podcast guys had a demo at vcf east that might of had that? Also, livingston portmaster 3s. This stuff should all be scrap now. Merlin Legend pbx can do t1 and analog and probably free now. On Mon, 15 Jul 2024, John Heritage via vcf-midatlantic wrote:
Thanks again Devin!
I think given the going $$ rate for ISDN Simulators+other equipment needed to support analog incoming RJ11 calls (i.e. the DIVA T/A ISDN Terminal), I think I'll give up on 56K for now. Hopefully I'll have a chance to see the full hardware set working in person at a VCF event in the future.
I am revisiting some of my past (BBS era, OS/2, etc). and just wanted to mess around with setting up a PCBoard BBS that could receive 56K calls, even if only within my home. (And mail a configured ATA to my father and have him dial in from his home using an analog modem. I also plan to try my hand at writing a file transfer protocol).
Thanks all for helping me understand this a bit more.
John
On Mon, Jul 15, 2024 at 5:57 PM Devin Heitmueller < devin.heitmueller@gmail.com> wrote:
Hi John,
Yeah, so back in the day the TCH was probably one of the most popular systems for large scale ISP termination of 56k calls. This was largely because a single card in a TCH could terminate a PRI and thus support up to 24 calls. And a TCH rack could hold a bunch of those cards. There were also TCH cards which had ISDN BRI interfaces and could terminate I think something like four calls. Another option that Dave mentioned is the Cisco AS5200, which can also terminate V.90 with the appropriate firmware. The one we had required a PRI interface; I don't recall if there was a version of the 5200 which took a BRI (which you could then use with your ISDN simulator).
So much of this comes down to what you're trying to accomplish. If you just want the person to know what it feels like to surf the web at 56k, then you can simply use two ISDN terminal adapters with an ISDN simulator in between and don't use both channels (in fact, you can connect at 56Kbps instead of 64Kbps assuming the line is properly provisioned). The terminal adapters can be any variant and don't actually need any analog support.
If the goal is for the user to hear the screeching of the client modem during connection, and you have an ISDN simulator at your disposal, then I would probably suggest that you still use two ISDN terminal adapters, but one of them should have analog POTS ports on it. So the client computer has an V.90 analog modem connected to the POTS port on the client ISDN terminal adapter, the ISDN simulator in the middle, and the server side has the Courier I connected, which will allow the call to be terminated at 56k.
It's worth noting that the quality of analog ports on various ISDN terminal adapters does vary. Some of the cheaper ones were good enough for voice calls but didn't really hold up when running a modem over them (and in fact some ISDN TAs had no POTS support at all). Personally I can only vouch for the 3Com ISDN gear I worked on as having analog support which was well-tested (3ComImpact IQ, ISDN Lan Modem, Courier-I).
Devin
On Sun, Jul 14, 2024 at 8:17 PM John Heritage via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
Devin - Thanks for the info; What were ISPs using then to take 56K calls outside of the USR Total Control racks and Courier I Modems?
Also, Devin/others - the link from above:
https://www.reddit.com/r/retrobattlestations/comments/t5m6od/56k_upgrade_to_...
.. If I wanted to simplify to support one 56K call internally between an analog modem (originating) and the Courier I-Modem (receiving), besides
the
Dialup Server and ATA, is there any way to drop the DIVA T/A Terminal and just use the I-modem with ISDN simulator?
For ease of reading, his hardware list was as follows:
-
Cobalt Qube 2 Dialup Server -
Teltone ILS-2000 ISDN Simulator -
US Robotics Courier I-Modem -
DIVA T/A ISDN Terminal -
US Robotics Courier V.EVERYTHING Modem -
Grandstream HT802 ATA
On Wed, Jul 3, 2024 at 11:55 AM Devin Heitmueller via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
For what it's worth, everything everybody here has said I agree with. The only point I would add is that the Courier I was the only ISDN terminal adapter on the market that can terminate an analog call at 56k. In other words, it can't simply be an ISDN terminal adapter with an analog modem behind it.
Nowadays you can buy entire Total Control racks for a few hundred bucks on eBay. Of course you do still need some sort of switch to route the calls over (in the ISDN lab I worked in when I was at 3Com, we had a Siemens switch which let me do all sorts of such combinations). And if you're only looking to terminate a single 56K connection the TCH is massive overkill and a Courier I would do just fine.
While talking about the Courier I, probably also worth noting that while in theory it can digitally terminate two 56K connections (since ISDN has 2B+1D), the analog modem subsystem can only terminate a single analog call.
Devin
On Wed, Jul 3, 2024 at 11:24 AM Jonathan Chapman via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
Getting closer. The dialin line that comes out of the 56K modem bank
actually runs over the digital side, you won't need a POTS line simulator, you'll need a FXS line card. Probably the simplest (least hardware, that is) way to accomplish what you want is to drop a dual T1 card in an Asterisk box and plug in an ADIT 600 or similar. You may be able to accomplish it with a Cisco ISR that supports voice cards like the Cisco 2800, too.
The most common carrier-grade hardware for running 56K is going to
be a rack mountable unit with 23/24/46/48 digital modems in it, like the US Robotics Total Control. They take one or more T1s in the back for the "voice" lines, and various things for the Internet end (V.35 sync serial, ATM, Ethernet, etc). We may actually still have a spare kicking around, I'll check and see if it's available if you're actually interested in running such a monster.
If you really want to run 56K you are going to need to "simulate"
most of the phone company. "Simulate" in quotes because you'll be actually implementing a tiny central office.
There will be nontrivial dialplan programming/configuration
required, no matter what you go with. Other folks have had this going though -- TangentDelta had such a setup running when he worked here, and I think ShadyTel has done it in recent memory. If you're going to be at VCF MW, there's going to be a pretty extensive telecom setup that would likely answer most of your questions.
Thanks, Jonathan
On Monday, July 1st, 2024 at 20:56, John Heritage via
vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
Ok I've been thinking about this a bit more. Is all of the
equipment
required as follows:
"iSP" / receiver end - a modem capable of interfacing digitally and talking to analog modems. (I.e. USR Courier I-modem).
An ISDN simulator to create the digital connection.
A telephone line simulator - to provide dial tone and handle call routing between the ISDN simulator and your analog modem.
Of course a computer on the "dial end" with a terminal program, and either ISP software or a BBS application, or terminal program with auto answer capability at a minimum on the "ISP side".
The digital side avoids an extra DA conversion which is what allows the 56K "download" from the 'callers' perspective.
Do I have it now?
Thanks!
On Mon, Jul 1, 2024, 6:18 PM John Heritage john.heritage@gmail.com wrote:
> Thanks Dean, Gregg, and others -- that's what I wanted to confirm, to make > sure I understood there was another ("digital connection") component > required to enable "56K", and that there wasn't some simple method like > using two Courier I-Modems. I assume a line simulator alone won't do this > since the reddit poster used: a Dial-up server, an ISDN simulator, a T/A > ISDN terminal, and an ATA to make it work. > > I got out of the BBS scene a little early in 1994 (visit from Microsoft > and Novell), so I was familiar with HST, V.34, and compression methods, but > when I eventually got back into computers "with the internet", I never took > the time to learn how 56K really worked before switching to cable modem. > > Is anyone aware of any "hacks" that can simulate ISDN / DS0 stuff using a > Raspberry Pi or similar? or is it pretty much - go source old hardware > that does this if you want 56K for a home lab test environment? I can't > seem to find any via searching. > > Thanks! > John > > On Mon, Jul 1, 2024 at 10:55 AM Dean Notarnicola dnotarnicola@gmail.com > wrote: > >> 56K modems were never meant to direct connect to each other when both >> ends were terminated on analog POTS lines. I remember having to explain >> this to people back in the day that wanted to connect house to house or >> connect branch offices faster than 33.6K. Service providers had dialup >> Points of Presence that had incoming digital connections and could >> negotiate 56K. The upstream connection was established at 53K to 56K (under >> the right conditions) and the downstream connection back to the user was >> 33.6K max (analog.) >> >> David was right and you will definitely need to simulate a digital >> connection to get 56K. >> >> On Sun, Jun 30, 2024 at 7:12 PM John Heritage via vcf-midatlantic < >> vcf-midatlantic@lists.vcfed.org> wrote: >> >>> Hi Gregg! >>> >>> Right now they're just direct connected via q phone cable. No phone line >>> simulator was required for the 33.6kbps speed I'm getting. (Ignore dial >>> done on one modem works while the other answers via ATA). >>> >>> I'm just trying to understand all that is required to enable 56K >>> capability.. Thanks! >>> >>> On Sun, Jun 30, 2024, 6:40 PM Gregg Levine gregg.drwho8@gmail.com >>> wrote: >>> >>>> Hello! >>>> How are you connecting them together? You'd need two phones and and a >>>> phone-line simulator, or two phones and an ATA, see here for advice, >>>> https://gekk.info/articles/ata-config.html >>>> Finding them things is easy, oddly enough the one I used was from our >>>> free pile from a recent (not this year) swap meet. >>>> >>>> And the dinos are dancing in the light rain. >>>> ----- >>>> Gregg C Levine gregg.drwho8@gmail.com >>>> "This signature fought the Time Wars, time and again." >>>> >>>> On Sun, Jun 30, 2024 at 4:09 PM David Ryskalczyk via vcf-midatlantic >>>> vcf-midatlantic@lists.vcfed.org wrote: >>>> >>>>> I found a few other Reddit posts with details but don’t have them >>>>> immediately on hand. Pretty much yes, you’ll need digital phone line / >>>>> ISDN >>>>> hardware. >>>>> >>>>> David >>>>> >>>>> On Jun 30, 2024, at 4:04 PM, John Heritage john.heritage@gmail.com >>>>> wrote: >>>>> >>>>> Thanks! >>>>> >>>>> I was reading this reddit thread earlier, and was having a little >>>>> trouble following, so I wrote below to verify what I took away. >>>>> >>>>> (Thanks again) >>>>> >>>>> On Sun, Jun 30, 2024 at 15:43 David Ryskalczyk d235j.1@gmail.com >>>>> wrote: >>>>> >>>>>> There is a good writeup of what you’ll be facing here: >>> >>>
https://old.reddit.com/r/retrobattlestations/comments/t5m6od/56k_upgrade_to_...
>>> >>>>>> David >>>>>> >>>>>> On Jun 30, 2024, at 3:01 PM, John Heritage via vcf-midatlantic < >>>>>> vcf-midatlantic@lists.vcfed.org> wrote: >>>>>> >>>>>> Hi folks! >>>>>> >>>>>> I'm messing around with a bunch of modems at home, and would like to >>>>>> know >>>>>> what's required to set up one system to receive 56K calls from >>>>>> another >>>>>> system. >>>>>> >>>>>> I'm able to get 33.6kbps bi-directionally (or 31.2K) with just a >>>>>> phone >>>>>> line >>>>>> between the two modems, and using ATX1D and ATA commands. >>>>>> >>>>>> I think to get 56K I require some equipment to simulate a digital >>>>>> connection, and I'm also not sure if a 56K analog modem can even >>>>>> receive >>>>>> 56K calls. Is this true? >>>>>> >>>>>> Modems I have on hand: >>>>>> - a USRobotics Courier I-Modem >>>>>> - 2 x USRobotics V.Everything, and a USRobotics 56K/X2 Sportster >>>>>> external >>>>>> modem >>>>>> >>>>>> I am also unable to get the I-Modem to connect to any of the analog >>>>>> modems, >>>>>> and although it does have the protocols to support analog, it seems >>>>>> like >>>>>> it's expecting a BRI / ISDN connection to allow that connection. >>>>>> Is >>>>>> this >>>>>> true? >>>>>> >>>>>> If the above are true - what's the minimum / cheapest solution for >>>>>> being >>>>>> able to at least establish a V.90 connection given the equipment I >>>>>> have >>>>>> already? >>>>>> >>>>>> Thanks for your help! >>>>>> John