Open cpn AIS

sailaboutvic said:
Quick update
I manage to get everything working but only on UDP and nothing with TCP , plain to email DY to morrow and see what they have to say , report back once I got a answer.
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Hi Vic .... I'm probably stating the obvious here, so apologies, but have you selected UDP rather than TCP on the set-up screen for your AIS unit? Or perhaps your unit defaults to UDP and you have to manually select TCP? Some AIS units can do both and some can only do TCP.

Richard
 
RichardS said:
Hi Vic .... I'm probably stating the obvious here, so apologies, but have you selected UDP rather than TCP on the set-up screen for your AIS unit? Or perhaps your unit defaults to UDP and you have to manually select TCP? Some AIS units can do both and some can only do TCP.

Richard
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Hi Richard
As you see by the photo I just posted , you can one or the other.
I tried both .
 
sailaboutvic said:
Hi Richard
As you see by the photo I just posted , you can one or the other.
I tried both .
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Hi, screen shot looks like an app which is listening to what's being sent out ? So if you are only seeing anything on UDP then the AIS unit seems to be only sending out UDP, not that it matters much if it's working. I did some tests onboard and UDP seemed plenty fast and reliable enough for our uses like this.

https://digitalyacht.net/testing-wireless-nmea-data/
 
GHA said:
Hi, screen shot looks like an app which is listening to what's being sent out ? So if you are only seeing anything on UDP then the AIS unit seems to be only sending out UDP, not that it matters much if it's working. I did some tests onboard and UDP seemed plenty fast and reliable enough for our uses like this.

https://digitalyacht.net/testing-wireless-nmea-data/
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If set to TCP it should work , but for some reason it don't , although it did at one point .
 
sailaboutvic said:
If set to TCP it should work ,
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Looks like it doesn't ;)

Are you logged onto the “DY-iAIS-xxxx” wifi network? Quick look in the manual says it should be tcp on 169.254.1.1 Port - 2000 , but you said you changed the address..

Yes the new gate way is 192.168.1.1 port 2000 . We did have a problem a while back on the iPad and it came to light that when apple updated their iOS the old gate way stop working so we have to re program the unit with a file they sent up .
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Screenshot has the address 192.168.1.12. If it is working and only on UDP maybe that reprogram changed to just UDP as well?

Since it is working I'd be tempted to leave well alone, after leaving it on for a few days to make sure it doesn't get grumpy after a while.. ;)




Installation Step 5 – Wireless Interfacing• The iAIS receiver has an integrated 802.11b+g wireless adaptor which creates a wireless hotspot on-board yourboat. The SSID (name) of the wireless hotspot that iAIS creates will be where xxxx is a four digitcode unique to your iAIS.• To connect to iAIS, simply scan for wireless hotspots on your wireless device. The exact procedure will vary fromdevice to device so consult the user manual for your device to understand how to connect to a wireless hotspot.• The iAIS uses the TCP/IP protocol to transmit serial NMEA data and it is important that the program or applicationon the wireless device supports data reception via TCP/IP in order to work correctly.• Once you have wirelessly connected your mobile device to the iAIS, you will need to run the Application on yourmobile device that accepts NMEA data over a TPC/IP connection. The TCP/IP address and port that iAIStransmits data on are;IP Address - 169.254.1.1Port - 2000• You should now be able to receive data wirelessly from the iAIS.
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GHA said:
Looks like it doesn't ;)

Are you logged onto the “DY-iAIS-xxxx” wifi network? Quick look in the manual says it should be tcp on 169.254.1.1 Port - 2000 , but you said you changed the address..

Any way email off to DY , they where very helpful last time , see how they respond is time .



Screenshot has the address 192.168.1.12. If it is working and only on UDP maybe that reprogram changed to just UDP as well?

Since it is working I'd be tempted to leave well alone, after leaving it on for a few days to make sure it doesn't get grumpy after a while.. ;)
Click to expand...

I could just leave it working on UDP , but I have so much help here and no doubt at some point someone else is going to have the same problem , so it be good to get to the bottom of it if I can , it many just say someone else hours of messing around .
 
Vic, like GHA I think the pic you've posted is of an app accessing the data from the iAIS wifi router. From the link GHA's posted I'd guess its DYs iAIS app on your iPad ? The address of the iAIS device is probably 192.168.1.1, your iPad is 192.168.1.12, your tablet will be another in the same sequence of 192.168.1.xx.

In principle the difference between UDP and TCP is speed, with UDP being the faster. This is pretty much because it dispenses with the error checking and sequencing inherent in the conversational style of TCP. Essentially if you're streaming TV you can miss bits of data and it doesnt matter much - same with some NMEA or radar data (UDP is used by the Navico systems to stream radar data) - no doubt if I've got this wrong laika will be along to correct me :)

If you would share the question you've sent DY and thier answer we can help decipher it - it may also be an idea to start from scratch (ie reset to defaults) with the iAIS device and rebuild it all from there
 
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RobbieW said:
Vic, like GHA I think the pic you've posted is of an app accessing the data from the iAIS wifi router. From the link GHA's posted I'd guess its DYs iAIS app on your iPad ? The address of the iAIS device is probably 192.168.1.1, your iPad is 192.168.1.12, your tablet will be another in the same sequence of 192.168.1.xx.

In principle the difference between UDP and TCP is speed, with UDP being the faster. This is pretty much because it dispenses with the error checking inherent in the conversational style of TCP, essentially if you're streaming TV you can miss bits of data and it doesnt matter much - same with some NMEA or radar data (UDP is used by the Navico systems to stream radar data) - no doubt if I've got this wrong laika will be along to correct me :)
Click to expand...

I'll augment that statement :-) But first...As GHA and Robbie say the screenshot definitely looks like the DY client app and the "host" box should contain the address of the iAIS server. If I understand Vic correctly, he's uploaded new firmware to the iais server and it should be servicing up TCP on 192.168.1.1 port 2000. So that "host" box should contain "192.168.1.1" NOT "192.168.1.12" as shown.

A screenshot of the OCPN data connections set-up page would be helpful if that's the thing you're trying to get sorted.

I'm pretty sure the older releases of the iAIS only supported one tcp client at a time but there's no mention of that limit in the current manual so hopefully the firmware upgrade has done away with that.

To return to the speed thing...this is a bit of a segue and not germane to the preceding discussion so unless interested look away now...Robbie's own research on data rates for radar over wireless highlights that things get a bit different over wifi where what happens a layer below the whole tcp/ip thing is a big factor. Unlike ethernet, wifi is very prone to interference so it has its own acknowledgement, retransmission and rate adaptation built in. However without special tricks this only works when sending data point to point ("unicast"). For broadcast or multicast (where a sender is sending to everyone or everyone who's interested) there's no acknowledgements and no rate adaptation, so normally this gets sent at a low "basic rate" which all stations are deemed to be able to support. So broadcast/multicast data over wifi will (without special tricks) generally be slow and prone to a lot of data loss. UDP is just a way to wrap data which can be sent addressed to a single endpoint (unicast), everything on the local network (broadcast) or everything which has expressed an interest in listening (multicast). However the iAIS uses UDP to send broadcast data which, as we've just discussed, will likely be sent slower than point to point data. Does that matter here? Not really: the AIS data rate is a small fraction of even the 802.11bg basic rates. Packet loss might be a more significant issue meaning full AIS data might take a bit longer to appear on your device.

Radar over wifi is a different case because the data rates are much higher which is why radar units which advertise themselves as having wifi capabilities use point to point connections rather than multicast as radar units have done traditionally over wired connections.
 
laika said:
I'll augment that statement :-) But first...As GHA and Robbie say the screenshot definitely looks like the DY client app and the "host" box should contain the address of the iAIS server. If I understand Vic correctly, he's uploaded new firmware to the iais server and it should be servicing up TCP on 192.168.1.1 port 2000. So that "host" box should contain "192.168.1.1" NOT "192.168.1.12" as shown.

A screenshot of the OCPN data connections set-up page would be helpful if that's the thing you're trying to get sorted.

I'm pretty sure the older releases of the iAIS only supported one tcp client at a time but there's no mention of that limit in the current manual so hopefully the firmware upgrade has done away with that.

To return to the speed thing...this is a bit of a segue and not germane to the preceding discussion so unless interested look away now...Robbie's own research on data rates for radar over wireless highlights that things get a bit different over wifi where what happens a layer below the whole tcp/ip thing is a big factor. Unlike ethernet, wifi is very prone to interference so it has its own acknowledgement, retransmission and rate adaptation built in. However without special tricks this only works when sending data point to point ("unicast"). For broadcast or multicast (where a sender is sending to everyone or everyone who's interested) there's no acknowledgements and no rate adaptation, so normally this gets sent at a low "basic rate" which all stations are deemed to be able to support. So broadcast/multicast data over wifi will (without special tricks) generally be slow and prone to a lot of data loss. UDP is just a way to wrap data which can be sent addressed to a single endpoint (unicast), everything on the local network (broadcast) or everything which has expressed an interest in listening (multicast). However the iAIS uses UDP to send broadcast data which, as we've just discussed, will likely be sent slower than point to point data. Does that matter here? Not really: the AIS data rate is a small fraction of even the 802.11bg basic rates. Packet loss might be a more significant issue meaning full AIS data might take a bit longer to appear on your device.

Radar over wifi is a different case because the data rates are much higher which is why radar units which advertise themselves as having wifi capabilities use point to point connections rather than multicast as radar units have done traditionally over wired connections.
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First thanks everyone for your input , you know what it's like when you have a bee in your bonnet , that's me at the moment , like to get to the bottom of it and understand it a bit better .

Laika yes your right I did update the fire wall ,
DY sent me a new file which I program to the IAIS using Tera Tera program .
This had to be done because the last Apple update did some thing so we could not use the address we was using , it seem a lot of people had the same problem .

Anyway , That seen to work fine , but on our sail over to Tunisia we found it kept disconnecting on the iPad , at time not connecting at all but now and then work on the laptop , I guess the reason for that is the laptop was working in UPD.
Cut a long story short , doing some test we now found that we can get it to work in UDP on the iPad, laptop and tablet, although it taken a long time to connect up at times .
As for the last two numbers in the address box , according to DY last time we chatted , it makes no different if it's .1 or.11 or .12 ,
I tried all them combinations at one point or another , also did as Richard suggested and used 001. Without any luck.

I just checked the address in DY-IAIS connection and it says 191.161.1.11 ,
In the set up box I have it as 191.161.1.1 guess what it's connected straight away .
I start to wonder if there some thing I interfering with it in the Marina .

Putting that all to one side , so are you saying I can only have one connection set to TCP ? And any other connection set to UPD ?

Also why at time can I see target in one or two of the receivers and not on the third although it's listed in the AIS target box . ( all setting are set the same ) on all three ( iPad, laptop, tablet ) .

Hopefully you get the drift what I wrote , long posting get worst as I write , haha.
 
sailaboutvic said:
As for the last two numbers in the address box , according to DY last time we chatted , it makes no different if it's .1 or.11 or .12 ,
I tried all them combinations at one point or another , also did as Richard suggested and used 001. Without any luck.

I just checked the address in DY-IAIS connection and it says 191.161.1.11 ,
In the set up box I have it as 191.161.1.1 guess what it's connected straight away .
[...]
Putting that all to one side , so are you saying I can only have one connection set to TCP ? And any other connection set to UPD ?
Click to expand...

At this point maybe we make sure we're all on the same page with this problem. The original question was about OCPN on a tablet but the connection box we saw a screenshot for was for the DY ias app, presumably on an ipad?

The screenshot you showed of the DY client app had 191.168.1.12 as the server address. But you're saying you're using 191.161.1.11 or 191.161.1.1 (I'm not clear which) but it should be 192.168.1.1 . The address definitely *does* matter here.

I suggest we get one thing working then work on the others. Do you want to start with OCPN on the tablet or the DY app?

There's no mention of limits or otherwise on the number of connected TCP clients in the latest manual but the early DY iAIS units definitely limited clients to either one or two I don't remember which. If we start by turning everything but one thing off we can work on that. What do you want to start with?
 
laika said:
... research on data rates for radar over wireless highlights that things get a bit different over wifi where what happens a layer below the whole tcp/ip thing is a big factor. Unlike ethernet, wifi is very prone to interference so it has its own acknowledgement, retransmission and rate adaptation built in....
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Thanks, I hadnt understood that subtlety
 
RobbieW said:
Thanks, I hadnt understood that subtlety
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Me neither until I started looking at why multicast radar was rubbish over wifi. I don't normally do layer 2 :-)

But back to the subject matter...

I sent a mail to DY who confirmed that the iAIS only supports one TCP client at a time. They say that if you want to receive data on multiple devices you need to listen for UDP broadcasts on port 2000. On the DY app switching to "UDP" should grey out the box for the server address. In the OCPN connections page it doesn't matter what address you put in the box for address when listening for UDP broadcasts, but you might as well use what OCPN will do under the hood: "0.0.0.0". I think Vic was saying that everything is working with UDP, yes?

What I didn't manage to clarify (sent the last mail just before 5 so maybe will get a reply tomorrow: they were pretty quick in responding to the first couple of mails) was whether connecting a TCP client would stop the UDP broadcasts.

But the address for a TCP connection should definitely be 192.168.1.1 port 2000 following the firmware update which Vic has done
 
laika said:
I sent a mail to DY who confirmed that the iAIS only supports one TCP client at a time.
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I've learned something there. My Vesper Marine XB8000 AIS transceiver supports 5 simultaneous clients over TCP/IP so I had always thought that 5 must be some kind of technical minimum. I wonder why DY would deliberately limit their device to 1 client as that seems to be defeating one of the big advantages of wifi over cable. :confused:

Richard
 
RichardS said:
I've learned something there. My Vesper Marine XB8000 AIS transceiver supports 5 simultaneous clients over TCP/IP so I had always thought that 5 must be some kind of technical minimum. I wonder why DY would deliberately limit their device to 1 client as that seems to be defeating one of the big advantages of wifi over cable. :confused:

Richard
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Probably because using TCP the server needs to track responses from the clients, restricting that to 1 makes it easy
 
I did ask digital yacht about the 1 tcp client thing at a boat show a while back. I understand it wasn't a conscious choice: they buy in boards with firmware libraries to do the networking and that's just what it supports. I assume the firmware writers are implementing this as a single-tasking microcontroller thing without much of a nod to concurrency. The iAIS only supports "up to 7" wireless clients. I've always found it odd that a £400 device should contain software with such limitations but I think the expectations of folks in the electronics world and those in the computing world are taking a while to converge. The iAIS is a very old product: One of the first of it's type IIRC.
 
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laika said:
At this point maybe we make sure we're all on the same page with this problem. The original question was about OCPN on a tablet but the connection box we saw a screenshot for was for the DY ias app, presumably on an ipad?

The screenshot you showed of the DY client app had 191.168.1.12 as the server address. But you're saying you're using 191.161.1.11 or 191.161.1.1 (I'm not clear which) but it should be 192.168.1.1 . The address definitely *does* matter here.

I suggest we get one thing working then work on the others. Do you want to start with OCPN on the tablet or the DY app?

There's no mention of limits or otherwise on the number of connected TCP clients in the latest manual but the early DY iAIS units definitely limited clients to either one or two I don't remember which. If we start by turning everything but one thing off we can work on that. What do you want to start with?
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Ok starting with IAIS
If I go I got connection for my wifi it say address is 191.168.1.11

If I try and connect using that address is wont ( see photo .

If I try and connect using 191.168.1.1 it will connect after a while .

Using UDP setting it connect again after a while , it may time out a few times before it connect.
I take this to mean there a delay in the signal .

Question , why do you think it won't connect to the same address as the address in the wifi setting box ? I guess this is why I was having a problem getting it to work as I was using the wifi address setting .

Question , if I have say laptop tablet and IPad working at the same time do you think it be best to have them all set to UDP or by having the iPad set to TPC that there be a conflict? or does it not matter

Wait for your reply before going on to the tablet setting .
In the mean time what setting you suggested I use the table and laptop ?
Thanks for being patient.
 
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