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BBSes, Modems, and VoIP

I would love to see it done. Been meaning to try but hadn't made the voip commitment yet. The quality of the phone connections today (cell and voip) does a lot of compression so some think it may not work if it drops the quality low enough, but I think a lower baud rate would technically work, depending on quality of the connection. Certainly something to try if anyone has the spare time and gear already in place.
 
I've gotten into retrocomputing hardcore over the past few months. I used to run a BBS as a kid, and had a linux box with a VT-220 terminal next to my bed, just because it was fun. It was fun being up at like 1am on friday and saturday nights dialing into all sorts of random BBS to find random things.

They were like hyper-local internet pockets. I feel that people need that again. The purity of a dialup 2400 baud modem, taking time reading characters, etc. I hope that at some point there could be a resurgence of retrocomputing enthusiasts that could have a healthy network of dialup bbs humming along and creating a new culture. It's like the rebirth of the flapper era now, with Boardwalk Empire and the like. Sure, it's complicated and takes a lot more time than it should have, but that's the point. It's cool because you have to put in the work.
 
Well, there are two realistic definitions of "VOIP".

1. A 100% internet/computer-based voice system, such as Skype or Google Voice. Obviously, there is no way to interface a modem with these, so you can't be talking about these.

2. A VOIP-to-POTS adapter that lets you plug a conventional RJ-11 telephone into a box that connects to the internet and provides dial tone and telephone service. This would be something like MagicJack or Vonage. These, in theory, will work with a modem.

I have used a VOIP-to-POTS service (Packet 8, similar to Vonage,) with a fax machine before, and had to turn the transmission speed down (to between 2400 baud and 9600 baud,) to get a reliable connection - which means you should be able to connect using a conventional data modem at those same speeds.
 
VoIP modem connections kind of suck. I managed a VoIP office system for one of my previous employers. Even with compression on our end turned done and high quality Digium boards, sending fax over VoIP was far from adequate. We did have good luck with using the VoIP PBX to switch faxes from a POTS line during business hours (the line was switched to other uses after hours, and served as failover if the Internet link or SIP trunk failed).

If you do get it to work, don't expect more than 300 or 1200 BPS. That's all we ever managed.
 
Here has been my experience:

With Vonage, I can dial out to another BBS as long as the other BBS has a real POTS line to dial into. I cannot however get VoIP to VoIP dial-up to work, even down to 300bps (although it's better). It appears that the compression is just too much for the signal, although the lower baud seems to a help a little, but not enough.

I have magic jack now, but have not tried a modem on it yet, I suspect it may work the same though. I also have not tried a normal POTS dialing into a VoIP, but it should work.

As far as faxes go, faxes worked fine on my Vonage line.
 
If your voip system is using a speech codec you wont be able to hit more than 2400 and 1200 will be iffy. Even if you are connecting through only a local LAN using full bandwith channels (pcm) between a pair of FXS ports, the packetization jitter will likely cap the speed at 9600. You really need a local circuit switched connection (key system/PBX) or ISDN card with modem emulation.
 
RetroHacker_ and I are currently experimenting with VoIP and modems. I've got an Asterisk box with some pretty high quality Digium analog hardware, and so far 300 baud has been painfully error prone to non-functional. RetroHacker_ reports better luck with 2400 baud modems with another friend over VoIP, due to the error checking available with the particular modems used. He also reports that his friend has had good luck with VoIP -> VoIP modem connections; that is, one VoIP number calling another.

It seems that the point of real weakness is the link between the PSTN and the VoIP provider. It seems likely that this is due to VoIP providers trying to squeeze as many calls through as little bandwidth as possible.
 
Sure, did4sale for incoming and Flowroute for outgoing. They both come in through a pfSense firewall to an Asterisk box running Asterisk 10 on Arch Linux, kernel 3.2.6. The actual box is a 2.66 GHz Pentium IV with 2 GB DDR1 RAM and an 80 GB WD Caviar IDE disk. Ethernet is all gigabit after the router, which probably doesn't matter since VoIP for one channel isn't bandwidth-intensive. The modems have been plugged into a Digium WildCard TDM400 and a Digium IAXy -- results tend to be exactly the same with both, as one would expect if the VoIP provider -> PSTN link is the weak point.
 
This is a great thread - I too have a bit of the retro computing bug. I started out with a 2400 baud modem and a 386 with an old version of DOS back in the day. Tied up my folks phone lines for hours dialing BBS's! I got a hold of an old Apple IIe which actually predates my original setup by quite a few years, I'm dying to take this puppy online through it's modem. Only problem is that I don't have a conventional phone line. VoIP seems like a possible solution. I started another thread under the apple forum. I'm wondering if there's a way to convert the analog line out of the modem into an ethernet port with some sort of adapter like a MagicJack or something? An Uthernet card would be a dream...but I'm not holding my breath for one of those anytime soon.
 
I know everyone is talking about using modems and such, but I’ve always thought of putting up a BBS and allowing people to telnet to it. I used to run a Renegade BBS back in the day and I would put it up again if people were willing to “call it” (telnet).

I suppose if you want the speed of a 2400 baud modem, you could set your terminal interface to 2400 baud. :)

There is a program called mTelnet for Windows which seemed to work pretty good for me when I tried it about 10 years ago. You can find it here.
 
Dante Trasatti said:
Not sure I follow you...PM me if you could. I don't want to change the thread's direction too much..
Click to expand...

It's been discussed here before. Set one modem to answer mode and leave your Apple modem to originate. Go off-hook with the answer modem and the originate modem will connect. Shove anything down the answer side that you want--run a BBS, for example.

It's mostly a matter of connecting and finding the right software.
 
Two great programs for running a bbs on a old machine.

1. BBS Server by Leif Bloomquist, This program seem to have many more features for the bbs auto/answer and disconnect.
(I can get my c128 with centipede to work with this one.)
It also supports modem emulation for outgoing.

http://www.jammingsignal.com/leif/bbs/

2.TCPSER

This is a program from Jim Brain that supports modem emulation, with multiple modems in a modem pool.
It's available in most linux distros, and a java version is also available.

TCPSER Windows exe.
http://www.jbrain.com/pub/linux/serial/

TCPSERJ (Java Version, it's what I prefer.)
http://www.jbrain.com/pub/xplatform/serial/

These solutions leave the modems out of it and use a serial port to the pc and emulate a modem with incoming on a definable port.

Later,
dabone
 
Problem, da, is that he's using an Apple II with a modem card. Not sure if he even has a serial card in the box. If that's the case, it's modem-to-modem.
 
I've done quite a bit of research into using analog modems with various ATAs and VoIP services. A number of publications, including those from Cisco, list various recommendations for optimal modem-passthrough support. Some of the more important recommendations include:

- Use of a G.711 CODEC
- Packetization of 10ms - 20ms
- Disabling the echo canceller and voice activity detection / comfort noise generator
- Fixed, 200ms jitter buffers

From my own experience, I would like to add that V.34 and V.42bis compatibility is a must for whichever modem you'll be using. The newer your modem is, the better off you'll be.

I'd looked into a number of ATAs, including highly-configurable ones from both Cisco and Obihai, but opted to try the all-in-one, single-purchase package that is the NetTalk Duo WiFi.

"WHAT!? WiFi and VoIP with an analog modem!? That's got to be the suckiest thing ever!"

No, it actually works a lot better than even I thought it would. I'm pretty pleased, in fact. :)

While the NetTalk device isn't as configurable as some of the others, I was able to get the G.711 CODEC prioritized over the default, G.722 option. This change alone has resulted in consistently solid 14400bps connections using a newer USR 56k modem, and 19200bps connections (matching the DTE rate) using my Diamond SupraSonic modem. That's not to say that there isn't some inconsistency - the range has been between 9600bps and 26400bps - and given the error-correcting involved, I hesitate to say that the performance matches the connection rate, but overall, and given a week's worth of testing, I think the Duo WiFi is a well-performing, inexpensive option for casual dial-up use.

One bit of unfortunate warning: NetTalk isn't for everyone. I certainly recommend doing your own homework regarding any product or service provider, but can say that my experience with them has been pretty stellar so far.
 
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