Some questions for those who have tried netlink with VOIP

[SEGA RPG FAN]

I've been researching VOIP as a possibility for netlink, and I've read that some of you have tried to use it unsuccessfully. What were some of the specifics of what you tried?

In other words:
Did the netlinks connect at all?
What provider(s) did you use?
Was it a voip line to land line call or voip to voip?
Did you try changing audio codecs? (G711 is supposed to be "lossless")

Thanks, I just want to get some feedback before I waste some time/money on this.

[Warp2063]

I've been researching VOIP as a possibility for netlink, and I've read that some of you have tried to use it unsuccessfully. What were some of the specifics of what you tried?

In other words:
Did the netlinks connect at all?
What provider(s) did you use?
Was it a voip line to land line call or voip to voip?
Did you try changing audio codecs? (G711 is supposed to be "lossless")

Thanks, I just want to get some feedback before I waste some time/money on this.

-The game systems would try to connect for a long time, then give up. In rare occasions, it would let you get to the opponent display screen, but even more rarely would you make it further than that.
-A bunch of different providers were tried. I don't know specifically which ones.
-VOIP to land line, land line to VOIP, and VOIP to VOIP have all been tried. With very rare exception, it never works.
-To my knowledge, no. The users used whatever codec that was the default from their provider. Most people had a specific conversion box for their house, given to them by whatever company was charging them monthly fees. As far as I know, no one had their own VOIP box that they themselves had chosen.

I suspect the problem is one of synchronization, not audio quality. The XBAND and NetLink require VERY precise timings to work properly. I believe that the analog-digital conversion and then transmission time is what slows it just enough to be problematic. When the NetLink detects that it is losing synchronization, it pauses whatever the system is doing for a moment in an attempt to resynchronize. I believe this to be the long pause when you first try to establish the call - a whole bunch of short pauses lined up before it gives up and gives you an error message.

[SEGA RPG FAN]

This was an interesting read: http://www.telephonyworld.com/training/ ... cy_wp.html

The main reason I was asking about audio codecs was because they affect not only the quality of the audio but the latency as well.

The G.711 codec (which i believe many VOIP adapters can be set to use) should result in the best quality with the lowest analog to digital processing time because there is no compression.

If two VOIP adapters could connect directly to each other, this would further decrease latency. This can be done with unlocked adapters but I'm not sure about stock equipment from a provider like Vonage for example.

[rush6432]

Intresting info.... id like to know if say magicjack or the netduo can do this direct p2p connection stuff. if so we may have a way to netlink again in the new age

[JerryTerrifying]

Magic Jack doesn't work. It doesn't work very well in general and doesn't work at all with Netlink. I'd say just get an analog phone line if you're interested.

[rush6432]

Magic Jack doesn't work. It doesn't work very well in general and doesn't work at all with Netlink. I'd say just get an analog phone line if you're interested.

its all connection dependant. we know that by itself out of the box the magic jack wont work with netlink. however with a few tweaks someone has already proven it can.....

[rush6432]

The codec the magic jack or voip unit uses for transmission is the culprit.

i know for a fact the sega mega modem will probably work over G.726 codec as that codec was built to work with slower modems. yes built for modems.... however that modem is slow (1600 to 2400 baud) and thats the reason why it will work.

faster modems like the netlink modem. you havn't really got a chance in hell unless you write the codec yourself. most of the codecs for modems over a magic jack type connection only allow for a maximum speed of 14.4 kbps...


Very good document http://www.soft-switch.org/foip.html about this topic and why some stuff works and others do not.

There is a point where the modem speed exceeds the speed that the codec can ENCODE the digital info and send it over the internet and un pack it. if you exceed that speed then it starts losing info and packets thus causing lag or connection problems. if the netlink modem could be set to 14.4 speeds (like the japanese counter part, you could play this over the modem probably on magic jack.

[SEGA RPG FAN]

With a normal modem and dial-up procedure you could just use ATA commands to specify the speed to connect at. I don't know how you would achieve this in a direct-dial environment though.