On Nov 2, 2012, at 6:14 PM, Peter Lothberg wrote:
If you guys actually try to do DECnet over radio I'd be interested...
=20
As long as you have a link-layer that takes a packet in and spit's it
out on the other side, taking care of retransmission, FEC coding etc,
it should work.
More precisely, you need either (a) a point to point reliable channel (anal=
ogous to DDCMP) or (b) a multicast datagram channel (analogous to Ethernet)=
.
IP over packet radio uses the latter, via the datagram mode of AX.25. That=
's a reasonable option for DECnet as well if the packet loss rate is low. =
If it's high, then the connection mode of AX.25 is a more efficient option,=
in spite of the design bugs that AX.25 inherited from X.25 and HDLC.
I was assuming using the "PTP" link mode.
The "error profile" of a HF chanel is such that the chances of
transmitting a packet without error with just HDLC decreeses with the
lenght of the packet. Ie, you might retransmitt the 576 byte packet
forever, having different bits being corupted every time.
To do this succesfull on a HF chanel, you need some kind of forward
error correct scheme.
There is a "hard decition" FEC named CI-BCH-3, that does better than
10db.
AX.25/HDLC likes VHF FM chanels with HIFI quality.
-P
On Nov 2, 2012, at 6:14 PM, Peter Lothberg wrote:
If you guys actually try to do DECnet over radio I'd be interested...
As long as you have a link-layer that takes a packet in and spit's it
out on the other side, taking care of retransmission, FEC coding etc,
it should work.
More precisely, you need either (a) a point to point reliable channel (analogous to DDCMP) or (b) a multicast datagram channel (analogous to Ethernet).
IP over packet radio uses the latter, via the datagram mode of AX.25. That's a reasonable option for DECnet as well if the packet loss rate is low. If it's high, then the connection mode of AX.25 is a more efficient option, in spite of the design bugs that AX.25 inherited from X.25 and HDLC.
paul
If you guys actually try to do DECnet over radio I'd be interested...
As long as you have a link-layer that takes a packet in and spit's it
out on the other side, taking care of retransmission, FEC coding etc,
it should work.
S9 on a clean 2.2Khz chanel is almost 2000 bit/s -:)
--P
On Nov 2, 2012, at 10:21, Cory Smelosky <b4 at gewt.net> wrote:
On Nov 2, 2012, at 10:14 AM, Brian Hechinger <wonko at 4amlunch.net> wrote:
Am I nuts?
Yes, but I like the idea.
Of corse you do. Compared to some of your ideas this is downright sane!!
:)
-brian
On Nov 2, 2012, at 10:39 AM, Sampsa Laine <sampsa at mac.com> wrote:
On 2 Nov 2012, at 16:31, Cory Smelosky wrote:
On Nov 2, 2012, at 10:21 AM, Sampsa Laine <sampsa at mac.com> wrote:
Doesn't DOSBox do exactly this with it's modem emulator, you basically ATDT <host>:<port> and it connects you over TCP/IP, presenting itself as a Hayes AT modem attached to a COM port to the DOS programs?
It's how I run Waffle's UUCICO on UUHECNET.
Anyway, the idea of actual, real, live, callable POTS numbers is cool too. Ooooh, could we somehow emulate ISDN over IP?
Could we? I have no idea. Will we? We must.
You know this will end with someone registering an ITU country code for HECnet..
Would this be a problem? :p
Sampsa
On Fri, Nov 2, 2012 at 10:39 AM, Sampsa Laine <sampsa at mac.com> wrote:
On 2 Nov 2012, at 16:31, Cory Smelosky wrote:
On Nov 2, 2012, at 10:21 AM, Sampsa Laine <sampsa at mac.com> wrote:
Doesn't DOSBox do exactly this with it's modem emulator, you basically ATDT
<host>:<port> and it connects you over TCP/IP, presenting itself as a Hayes
AT modem attached to a COM port to the DOS programs?
It's how I run Waffle's UUCICO on UUHECNET.
Anyway, the idea of actual, real, live, callable POTS numbers is cool too.
Ooooh, could we somehow emulate ISDN over IP?
Could we? I have no idea. Will we? We must.
You know this will end with someone registering an ITU country code for
HECnet..
Sampsa
Hello!
Now there is an idea.
Say Sampsa, why is there a poker convention of seven individuals who
might be cybermen sitting and playing poker......
-----
Gregg C Levine gregg.drwho8 at gmail.com
"This signature fought the Time Wars, time and again."
On 2 Nov 2012, at 16:31, Cory Smelosky wrote:
On Nov 2, 2012, at 10:21 AM, Sampsa Laine <sampsa at mac.com> wrote:
Doesn't DOSBox do exactly this with it's modem emulator, you basically ATDT <host>:<port> and it connects you over TCP/IP, presenting itself as a Hayes AT modem attached to a COM port to the DOS programs?
It's how I run Waffle's UUCICO on UUHECNET.
Anyway, the idea of actual, real, live, callable POTS numbers is cool too. Ooooh, could we somehow emulate ISDN over IP?
Could we? I have no idea. Will we? We must.
You know this will end with someone registering an ITU country code for HECnet..
Sampsa
On Nov 2, 2012, at 10:21 AM, Sampsa Laine <sampsa at mac.com> wrote:
Doesn't DOSBox do exactly this with it's modem emulator, you basically ATDT <host>:<port> and it connects you over TCP/IP, presenting itself as a Hayes AT modem attached to a COM port to the DOS programs?
It's how I run Waffle's UUCICO on UUHECNET.
Anyway, the idea of actual, real, live, callable POTS numbers is cool too. Ooooh, could we somehow emulate ISDN over IP?
Could we? I have no idea. Will we? We must.
Sampsa
On 2 Nov 2012, at 16:14, Brian Hechinger wrote:
Is it just me or does the whole conversion of serial to modem to pots to voip back and forth there seem a little excessive?
So I had an idea. What about a software modem that natively talks VoIP.
Then I had a better idea. I'm going to look into writing something similar to Johnny's serial bridge program only making it a proper "modem" with enough of the AT command set to be able to dial numbers and then make "phone numbers" actually be IP+port somehow.
Am I nuts?
-brian
On Nov 2, 2012, at 8:53, Joe Ferraro <jferraro at gmail.com> wrote:
If someone in the states gets something going, let me know.. I'd like to do an initial test to see if I can connect over my voip lines (may have to do a little tweaking). I attempted to connect with Sampsa a few years ago, unsuccessfully; however, I'm almost certain it had to do with switching VOIP across the atlantic, as I've been somewhat successful connecting to C64 bbses in the US.
Worse case, I'll just buy a POTS line... but I prefer the free long-distance.
On Fri, Nov 2, 2012 at 8:15 AM, Fred <fcoffey at misernet.net> wrote:
On Thu, 1 Nov 2012, Cory Smelosky wrote:
Count me in for UUHecnet as well. Happen to have any dial in-capable systems Fred? I just got my modem working and you're in the same state and it might cut down on long distance. ;)
Modems? I've got modems ... I came from the days before all this high speed stuff.:) Let me see what I'd need to hook one up - however my Asterisk system is essentially in the way so an FXS card will probaby need to be purchased (they aren't that expensive, I have a card that will accept any four of FXS/FXO - only two are populated at the moment)
Fred
Somebody already did the heavy lifting in the Hercules IBM emulator they emulate an IBM 2703 with BSC and IIRC serial lines over TCP look thru the source and find a file named com adapt.c or something like that I suspect all you have to do is replace the front end to match DEC interfaces.
BSC would be neat since DECNet used that as long haul links - seem to remember that from a DEC class in DECNet in Albuquerque in the 1970s (or was it the 1980s .)
On Nov 2, 2012, at 10:21 AM, Sampsa Laine <sampsa at mac.com> wrote:
Doesn't DOSBox do exactly this with it's modem emulator, you basically ATDT <host>:<port> and it connects you over TCP/IP, presenting itself as a Hayes AT modem attached to a COM port to the DOS programs?
It's how I run Waffle's UUCICO on UUHECNET.
Anyway, the idea of actual, real, live, callable POTS numbers is cool too. Ooooh, could we somehow emulate ISDN over IP?
Sampsa
On 2 Nov 2012, at 16:14, Brian Hechinger wrote:
Is it just me or does the whole conversion of serial to modem to pots to voip back and forth there seem a little excessive?
So I had an idea. What about a software modem that natively talks VoIP.
Then I had a better idea. I'm going to look into writing something similar to Johnny's serial bridge program only making it a proper "modem" with enough of the AT command set to be able to dial numbers and then make "phone numbers" actually be IP+port somehow.
Am I nuts?
-brian
On Nov 2, 2012, at 8:53, Joe Ferraro <jferraro at gmail.com> wrote:
If someone in the states gets something going, let me know.. I'd like to do an initial test to see if I can connect over my voip lines (may have to do a little tweaking). I attempted to connect with Sampsa a few years ago, unsuccessfully; however, I'm almost certain it had to do with switching VOIP across the atlantic, as I've been somewhat successful connecting to C64 bbses in the US.
Worse case, I'll just buy a POTS line... but I prefer the free long-distance.
On Fri, Nov 2, 2012 at 8:15 AM, Fred <fcoffey at misernet.net> wrote:
On Thu, 1 Nov 2012, Cory Smelosky wrote:
Count me in for UUHecnet as well. Happen to have any dial in-capable systems Fred? I just got my modem working and you're in the same state and it might cut down on long distance. ;)
Modems? I've got modems ... I came from the days before all this high speed stuff.:) Let me see what I'd need to hook one up - however my Asterisk system is essentially in the way so an FXS card will probaby need to be purchased (they aren't that expensive, I have a card that will accept any four of FXS/FXO - only two are populated at the moment)
Fred
There's a peripheral emulator for the 8-bit Atari computers called SIO2OSX. One of the peripherals it emulates is a modem. It simulates the AT command set enough for you to make a 'modem' connection to another IP address (and port number) using the Telnet protocol.
Because of this, you can use real BBS dialed software on your old Atari and instead of a phone number you put in an IP address. As far as the Atari is concerned, it's making a dial-up call.
Ian
Sent from my iPad
On 2012-11-02, at 7:14 AM, Brian Hechinger <wonko at 4amlunch.net> wrote:
Is it just me or does the whole conversion of serial to modem to pots to voip back and forth there seem a little excessive?
So I had an idea. What about a software modem that natively talks VoIP.
Then I had a better idea. I'm going to look into writing something similar to Johnny's serial bridge program only making it a proper "modem" with enough of the AT command set to be able to dial numbers and then make "phone numbers" actually be IP+port somehow.
Am I nuts?
-brian
On Nov 2, 2012, at 8:53, Joe Ferraro <jferraro at gmail.com> wrote:
If someone in the states gets something going, let me know.. I'd like to do an initial test to see if I can connect over my voip lines (may have to do a little tweaking). I attempted to connect with Sampsa a few years ago, unsuccessfully; however, I'm almost certain it had to do with switching VOIP across the atlantic, as I've been somewhat successful connecting to C64 bbses in the US.
Worse case, I'll just buy a POTS line... but I prefer the free long-distance.
On Fri, Nov 2, 2012 at 8:15 AM, Fred <fcoffey at misernet.net> wrote:
On Thu, 1 Nov 2012, Cory Smelosky wrote:
Count me in for UUHecnet as well. Happen to have any dial in-capable systems Fred? I just got my modem working and you're in the same state and it might cut down on long distance. ;)
Modems? I've got modems ... I came from the days before all this high speed stuff.:) Let me see what I'd need to hook one up - however my Asterisk system is essentially in the way so an FXS card will probaby need to be purchased (they aren't that expensive, I have a card that will accept any four of FXS/FXO - only two are populated at the moment)
Fred
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