TCP Connection Problems on Apple iOS 10


Since Apple’s release of iOS 10 for iPhones and iPads, we have been getting a number of calls and emails saying that various navigational Apps that read wireless NMEA data from our products have stopped working, including our free iAIS app.

There are two modes/protocols that our wireless NMEA products can work in; TCP which is a reliable one to one type connection supported by most apps and UDP which is a broadcast protocol that allows multiple devices to all receive the same data.

When we started to investigate, we found that TCP communication on all Apps no longer worked with iOS 10 and UDP only worked on some apps. At first we thought this might have been an Apple API type change that had caused the problem, but then we discovered that changing the IP address of our wireless NMEA products from to fixed the problem.

The IP address range is usually reserved for Ad-Hoc networks where there is no DHCP server and dates back to our first iAIS product (released in 2011) that only supported Ad-Hoc networks. With the release of Android, which did not support Ad-Hoc networks, we updated our wireless NMEA products to the more common Access Point mode but retained the IP address, to avoid changing too many Apps and Documentation.

Now it seems that Apple are clamping down on TCP connections on Ad-Hoc networks and this means that all customers who have updated their iPhone or iPad to iOS 10, will need to change the IP address of their wireless NMEA product, if they have one of our; iAIS, WLN10, WLN10HS, WLN20, NavLink, PilotLink or AIT3000 units. Please note that our iNavHub and Sonar Server products are not affected by the iOS change.

To make this procedure as easy and simple as possible, we have created a new Tech Note that explains what needs to be done Click here to download.


Related media

Download our media resources

Share this article
Shareable URL
Prev Post

New Products for 2017 at METS – Hall 1:434

Next Post

Digital Yacht 2017 French Product Guide Now Available

Comments 23
    1. Hi Jason,

      First let us see if the wireless NMEA device you have is using the older address or the newer address. Go to Settings>Wi-Fi on your iPhone, connect to our wireless device and then after the “Tick” appears to the left of the wireless network name, click on the “i” Info icon to the right of the wireless network name. This takes you to the network properties page and you will see the IP address that your iPhone has been given.

      If it is, then you have nothing to worry about and everything shoud be fine. If it is then you need to follow the instructions on the Tech Note that we give you the download link to in this article.

      Best regards

      1. Hi Paul
        I am following the steps as per the tech note to change the IP address using the Terra Term program but when get the page which should give me the “hello” prompt it starts with hello and then continues steaming other data to the effect that I can not put in the $ signs to continue.I am using an Ipad air with IOS 10

        1. Hi Arthur,

          When you have AIS/GPS data coming in to the wireless interface you will see it streaming down the screen in TeraTerm, BUT it is possible to still type the three dollar signs $$$ and press the Enter key. Alteratively, you can copy the three dollar signs from a text editor, email, etc. and paste them in to TeraTerm using the Paste option under the Edit menu of Tera Term.

          Best regards

    1. Hi Austin,

      Yes we do and I have emailed this to you separately as it is not currently in a suitable form for general release.

      Best regards

      1. Paul, I just used my Mac to make the change. The folks answering the phone said it could not be done. I was going to send you the procedure, but if you already have it (basically the same steps, but using, then I will not bother sending what I did.

        1. Hi John,
          Well done for proving the sales team wrong, they always “err on the side of caution” which is probably a good thing really.
          Glad you got everything sorted and if you have anymore questions, please just let me know.
          Best regards

  1. (AIS3000) Made the update for iOS 10 and wifi is now working fine, unit is receiving info from other boats and sharing to plotter via NMEA2k just fine, but it’s not sending our information out. Any suggestions?

    1. Hi Martin,
      Glad you got iOS 10 sorted and your AIT3000 is sending AIS data to your plotter. As long as the Green Power LED is constantly ON, then this indicates that the AIT3000 is passing all of its internal tests and is happy with Power, GPS and the VHF aerial which it does a VSWR test on, every time it transmits.
      I would have a read of this article I wrote which might give you some confidence that your AIT3000 is transmitting, but if you have any more questions after reading this, please let me know.
      Best regards

      1. Green power is solid. Green wi-if light is flashing. Anything I can do to fix this without a laptop?

  2. I have a connection problem with the WLN10HS that I bought 1 month ago. My iPad is 6 years old. It is running under iOS 9.3.5. Settings tell me the software is up to date. I managed to connect 3 times in UDP (I think I tried 50 or 100 times over a period of several weeks in different locations : harbour, sea ….).

    A test with a brand new iPhone7 gave a good result with the Digital Yacht iAIS app. It connects immediately in different situations, with a warning on the iPhone that the Wifi is connected, but not to an Internet connection (and therefore not safe). With my iPad I do not get this warning.

    What do you propose me to do ? Would the problem be solved by changing the IP-address ?

    Beste regards, Katelijne

    1. Hi Katelijine,
      If your WLN10HS is only six months old then it should already have the IP address change and all of the latest settings. If you want to check, on either device go to Settings>WiFi to view the Wi-Fi networks select the WLN10HS, after the tick appears to show you are connected, click the little blue “i” info icon to the right and you will be taken to the settings for this network. In here you can see what IP address your iPad/iPhone has got and if it starts then the WLN10HS is bang up to date and has the IP address change.

      The warning on your iPhone about No Internet on this network is to be expected with the latest iOS 10 update and is a warning that Apple have introduced. Any device network like the WLN10HS that does not have an internet connection will trigger the same warning.

      Have you any other marine apps on your older iPad that are not on your iPhone ? More and more apps are using similar network services to those that the WLN10HS does and they can sometimes block other apps, so always best to close all background apps before running iSailor or any other navigation app.

      Please let me know how you get on.

      Best regards


  3. Hi ! I just wanted to let you know, that your version of iAIS 3.0 does not work with iOS 11.2.1

    I can enter the correct ip-adress and ports, in my case and 10110, when flipping the link, I can see the NMEA sentences coming in, but after 1 or 2 seconds the system stops and is stalled.

    1. Hi,

      I can confirm that our iAIS 3.0 app is compatible with iOS 11.2.1 which I am running on my own iPhone and it works perfectly.

      I am not sure what equipment you are trying to connect to as that IP address and Port are not ones that Digital Yacht use.

      iAIS is designed as a free of charge app for Digital Yacht customers to use and I am afraid that we cannot test and ensure compatibility with other 3rd party equipment. If it works great, but if for some reason (I suspect data rather than network settings) it does not work, then I think you will need to use another paid for app that promotes compatibility with 3rd party equipment.

      Best regards


  4. Hi Paul ,
    I would value your help to establish a good working TCP/IP link. After instelling properly the VHF and powerleads I get a good WiFi signal but no connection On either the iAIS app, iSailor or Navionics Boating HD. The WiFi is On IP but I get no link and the green led keeps flashing slowly.
    Looking forward for your advice.

    Kind regards,

  5. Hi I have purchased a “Nomad” Unit and in the absence of a formal manual I wondered if there is anywhere external to the app which describes how the system is supposed to work?
    I have had a lot of pain getting the functionality that I now have but as there is no way of determining if it is functioning correctly I don’t know whether I have 100% functionality. It was nice to trip across the note above, about the new TCP/IP address.

    1. Hi Jonathan,

      Our Nomad can be connected to a wide variety of wireless devices; iOS or Android phones and tablets, Windows PCs and Tablets, Macs and LINUX PCs or even a Raspberry Pi. What software or apps you can use with Nomad will vary from device to device and many generic navigation apps, will display the AIS and GPS data from your Nomad, but give no real indication of whether the Nomad is functioning correctly.

      The best software program for testing/diagnosing one of our Nomad units is the proAIS2 software for Windows or Mac. Simply install the software, plug the Nomad in to a USB port on the computer and you will be able to see all of the features and functionality of the Nomad. I produced this proAIS2 video to help people to use it…

      Additionally, if you have an Android device, our AISConfig App is a useful free tool for wirelessly checking on the status of the Nomad. Unfortunately we do not have a similar tool for iOS (Apple) devices yet but if enough people asked for one, we would certainly consider it.

      Best regards

      1. Hi Paul

        Thank you for this it is very helpful. However as I have a Mac without an external disc drive I have downloaded ProAIS2 For Mac from your website and it seems to be frozen.

        You may be able to cut and paste this URL. I do not have the original AIS2 disc with me as I have been trying to crack this intermittently since buying the Nomad last summer.
        Any suggestions gratefully received.

      2. Hi Paul Please ignore that last comment. After a couple of minutes and by disconnecting and reconnecting the ProAIS2 software came to life and is confirming that the unit is functioning correctly. Thank you for your help.

Comments are closed.

Read next