TCP Connection Problems on Apple iOS 10

img_2705

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 169.254.1.1 to 192.168.1.1 fixed the problem.

The 169.254.1.1 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 169.254.1.1 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.

 

New set of “How To” Videos on our Long Range Wi-Fi Products

WL510+iNavConnect

Getting a good long range Wi-Fi connection in a marina can be a challenge, particularly if you have not used the equipment for a while and cannot remember the steps involved.

To try and help make this a little easier, Digital Yacht have created a set of “How To” videos that explain how to connect to the two main types of wireless hotspots that you will come across on your travels; the “Open” captive portal type hotspot favoured by most marinas these days and the “encrypted” password protected hotspot that most bars and restaurants still operate.

At the same time we also created a third video that covers the important process of securing your boat’s wireless, by changing the default wireless network name and password, so that only the people you want to connect, can join your network.

We recommend watching them in the order shown below and simply click on the link to take you to the video on our YouTube channel…

  1. Connecting our WL510 to a Captive Portal type Marina hotspot
  2. Connecting our WL510 to a Password Protected type Restaurant/Bar hotspot
  3. Changing the default SSID and Password on our iNavConnect/iNavHub/iKConnect routers

IMPORTANT NOTE
After Apple changed the way their auto login feature of iOS and Safari behaved earlier this year, we now recommend installing the free Google Chrome web browser for maximum compatibility when connecting to hotspots, on your iPad or iPhone and this is also true on Windows PCs as Internet Explorer does not always seem to trigger the re-direct to the marina’s welcome/login page.

Wi-Fi Congestion

WiFiAnalyzer

The range of 2.4GHz frequencies reserved for Wi-Fi is fairly limited and with so many Wi-Fi devices and networks these days, it is not unusual for wireless networks in the same location to share the same frequencies and this results in lower connection speeds and even connection drop outs in extreme situations.

The good news is that the wireless network(s) on your boat, once out at sea, will not be affected by the wireless networks on land or on other boats. That said, these days it is not unusual for larger yachts and powerboats to have two or more wireless networks and so it is really important to ensure that your own wireless networks are working at peak performance and not sharing the same frequencies.

The good news is that most Wireless Routers and Access Points can be configured to work on a specific frequency and so you should be able to ensure that each network is using its own frequency band without any overlaps.

There are affectively 13 frequencies in the 2.4GHz range and each wireless router will use five adjoining frequencies to setup its network. Looking at the diagram above, where each coloured curve is a separate wireless router/network, you can see that in general three frequencies are used; 1, 6 and 11. which allows three routers to work side by side with no overlapping/sharing of frequencies.

So how do you optimise the frequencies used by your wireless networks ? Well first you need to “see” what is going on by carrying out a wireless survey of your boat. This can be done using a number of free programs and apps. Unfortunately Apple do not allow iPhones and iPads to provide this level of Wi-Fi Information so you will need to use a Windows PC or Android device to do your wireless survey.

If you have an Android phone or tablet, then you are in luck as the free App “Wi-Fi Analyzer” is one of the best tools available and created the image above. For Windows PC users then “NetSurveyor” is very good or “WiFiInfoView” which is not so graphical but is only a few hundred Kilobytes in size and needs no installation, so can run straight from your memory stick.

Whichever tool you use, once you have conducted your wireless survey, you will be able to see what frequencies your wireless networks are operating on and decide if you need to change them. All Digital Yacht wireless products can be changed to use a different frequency and should you need to do this, please contact us for instructions.

Testing Wireless NMEA Data

iAIS TCP-IP Screen

 

With more and more wireless NMEA systems being installed on-board boats, it is very useful for dealers, installers and enthusiastic end users to have simple tools to “view” this wireless NMEA data.

Traditionally, wired NMEA0183 data was viewed using an NMEA to USB cable connected to a PC and then a program such as Hyperterminal (included with Windows up to WinXP) would be used to display the data. In fact Digital Yacht released a free, dedicated NMEA Display program to use on Windows Vista/7/8 and this proved to be a popular tool for testing wired NMEA0183 systems.

With wireless NMEA systems it is much easier to test using a smart phone or tablet and we would recommend the following free apps;

For Apple iOS Devices – our own free iAIS app (see image above) has a very simple raw data view window that can be used to display the wireless NMEA data in TCP or UDP mode. Alternatively iNMEA Logger is another free app, written by the company that developed the popular iRegatta App that can log 30 seconds of received data and create a text file of the results, useful if you do not understand NMEA0183 and want to send it to someone who does.

For Android Devices – there are no specific wireless NMEA Apps, but there are a lot of terminal programs that display TCP and UDP data and after trawling through a fair number of apps, we came across TCP/UDP Terminal App which we think is the best Android App found so far.

Once you have installed your app for displaying wireless NMEA data, then you need to know what you are looking at. To buy the NMEA0183 Specification costs quite a lot of money but there is quite a lot of data on-line, you just need to hunt it out.

Unfortunately a lot of the information on-line is quite old and some of the newer sentences are not fully explained. The NMEA do in fact publish a complete list of all Sentence Identifiers with a short description of what they are (not the complete sentence description) and this list also includes the proprietary Manufacturer’s ID – these sentences start $Pxxx, where xxx = the manufacturer identifier.

It should be noted that most wireless NMEA data is “human readable” (ASCII Text) but the AIS sentences VDM and VDO have what is called a “binary encapsulated” section (bit like a zip file) to reduce the sentence length – see example below.

!AIVDM,1,1,,A,13P;QeO001wrdB`M28kpmCa<0Ua0,0*5D
!AIVDO,1,1,,,B00000@00ovdqaWAUv“CwkUsP06,0*20

This means that you will not be able to make sense of the AIS target information in the VDM and VDO messages, but our free iAIS app does display this information on the main plotter screen, so worth having a copy of this app.

Digital Yacht Tech Training – A great resource

We’ve decided to publish our dealer training presentations on line so that the whole boating community can benefit.  Paul Sumpner, Digital Yacht’s CTO, was at the CA Clase distributor training event this week and presented a great overview on some of our core technologies including:

  • AIS – Hints and tips on transponder operation, programming and antenna selection
  • Wireless NMEA – differences between TCP/IP and UDP connections and app integration
  • GPS antennas and interfacing
  • Wireless internet and routers including common problems with accessing marina hotspots

Most importantly he covered lots of installation issues with hints and tips and important product selection advice.  Of course, reading a presentation on line is not as good as hearing the real thing so if you do have questions, feel free to contact us.

You can download the presentation from HERE  or click the picture below

tech training front cover

 

What’s in a Name ? – Good and Bad SSIDs

Bad SSID

We have noticed that quite a few of our WL450 and WL510 customers are using their long range Wi-Fi installation to connect to a “personal hotspot” or “tethered phone” depending upon whether they are an Apple or Android user. If you have a good or unlimited data plan on your phone, then this is a very useful way to get internet in places where the Wi-Fi is not so good but the 3G signal is strong. Normally it is the other way round, but if you find yourself in this situation, it is a “good tool to have in your tool box”.

The long range performance of the WL450/WL510, means that you can place the phone anywhere on the boat to get the best 3G signal and the WL450/WL510 will connect to it. If you also have the WL450/WL510 connected to a router like our iNavConnect then everyone on board connected to the router, will also be able to use the 3G internet connection.

Last week we were contacted by a customer trying to do just this with his iPhone but he could not get his WL510 to connect to his personal hotspot. After a bit of head scratching, we realised that he had an apostrophe in the SSID like the one in the image above “Paul&Kay’s iPhone” and this use of a special character was stopping the WL510 from connecting to it.

Looking online there did not seem to be a definitive Specification or RFC that stated what characters must or must not be used in an SSID, but the general recommendation seems to be that SSIDs should use standard characters, avoiding the use of special characters and spaces. So in our example above a much more compatible SSID would be “PaulandKays_iPhone”.

Once we changed the iPhone’s name (SSID) to a more compatible set of characters, the WL510 connected first time and he was able to get a very good 3G connection in the Norwegian Fjord he was moored in !