TCP Connection Problems on Apple iOS 10

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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.

 

National Coast Watch Doing a Great Job

NCI Mablethorpe Station

Since their formation in 1994, the UK’s National Coast Watch Institution (NCI) have been doing invaluable work around the UK coastline. With 50 stations, manned by over 2000 volunteers, the NCI are the marine watch keepers, alerting and coordinate MCA and RNLI rescue operations whilst also monitoring the general coastal environment and weather conditions.

A number of the NCI stations have Digital Yacht AIS units installed, including Mablethorpe (shown above) and the most recent installation was recently completed at Barry Island in South Wales (image below). Using one of our latest AISNet units, they were able to receive AIS targets all the way across the Bristol Channel and up the Avon.

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It is not always possible to get an internet connection in some of these very remote NCI stations, but in the Barry station, AISNet was able to send live reception data to an AIS webserver hosted by PocketMariner where it could be viewed online or on a mobile device using their Boat Beacon or our NavLink apps. The image below shows the typical reception the NCI station would see and you can click here to see a live view of the Barry Island station.

Boat Watch Live View

The NCI is entirely staffed by volunteers, with funding managed by a Board of Trustees based on a constitution agreed by the Charity Commission. It may not be as dramatic and high profile as the RNLI, but the work they do is of equal importance and relies heavily on local support and donations. If you ever chance upon an NCI station, just knock on the door and the officers on watch will give you a warm welcome and be delighted to show you what they do.

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Wi-Fi Congestion

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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.

NavLink iOS App Gets Canada Charts

NavLink US is Digital Yacht’s popular and low cost charting app for iOS devices.  It utilises detailed NOAA Government charts for excellent detail and clarity of US waters.  Navigate in real time, create routes and waypoints and connect to your boat’s GPS and AIS system via any of Digital Yacht’s NMEA-WiFi servers for real time AIS overlays and reliable positioning.  Your iPhone or iPad is transformed into a powerful, simple to use, touch screen chart plotter.

IPAD AIR MONTAGE TRANSPARENT

AIS presentations are fantastic with vessel scaling and course prediction vectors – advanced visualisations that really enhance navigation safety.

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Detailed Canadian Office CHS charts have now been added as a low cost (US$29.95) in app purchase.  To get NavLink US, simply visit the Apple App Store on your iOS device and download the app.  Contact us directly for details on our NMEA to Wireless devices for complete on board integration – details HERE

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Digital Update Feb 2015 Now Available

Digital Update is Digital Yacht’s monthly newsletter keeping you abreast of the latest marine electronic developments.  You can download this month’s edition from HERE
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In this month’s edition we look at our new AISnode NMEA 2000 AIS receiver as well as upgrades to our NavLink iOS and MAC apps for navigation.

 

 

USCG Class A AIS Mandate Now Approved

If you own or operate a commercial vessel in US waters (ports, rivers, lakes, and seas) you are likely to be affected by this new rule. The United States Coast Guard is publishing a new rule which will require most commercial vessels operating in US waters to fit and operate a USCG certified AIS transceiver. On 23rd December 2014, President Obama signed the final rule documentation relevant to the new USCG AIS Rule. We expect it to be formally published in the coming weeks whereupon those vessels affected shall have a limited window of 7 months to install an AIS Class A transceiver to be operating legally.  Currently only vessels over 300GRT on an international voyage are required to have an AIS Class A transponder.  It is likely this ruling will impact on 40,000 vessels.

AIS Basics

An AIS transponder send your boat’s identity, position, course and speed to other vessels equipped with an AIS unit. This data can then be interfaced to a chart plotter display to present an overlay of targets with their heading information.   It greatly aids navigation and helps with collision avoidance.  Signals are transmitted over two dedicated VHF frequencies so typical range from a Class A unit is 20-30NM depending upon antenna height.  All commercial ships over 300GRT are mandated to carry a Class A AIS transponder and the new USCG ruling will also mean other commercial vessels in the US will require a Class A unit.  Class A units have a display to show an overlay of targets and also connect to the vessels electronic chart plotter.  Voyage data can be entered into the Class A display.

Other users including yachtsmen can opt for the cheaper Class B type units like the Digital Yacht AIT1500/AIT2000/AIT3000.  Class B units are fully integrated into the AIS system but have a lower 2W transmit power and only send their data every 30 seconds.  They also require a chart plotter to display target data

What equipment is required?

A USCG approved Class A transponder like Digital Deep Sea’s CLA1000 meets the requirement of the mandate.  Its built tough, is extremely reliable, fully approved and competitively priced as well as supported through a technical dealer network.

The CLA1000 requires two antennas – a GPS antenna (included) and connection to a dedicated VHF antenna.  It may be your vessel already has a spare VHF antenna but if not a good quality (3dBi) VHF antenna should be fitted and ideally a version which is tuned to AIS frequencies (162MHz) which are slightly higher than the normal 156MHz range used for voice traffic.  Digital Deep Sea can help specify the right antenna for your vessel and even have a bundle package available

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The picture above also shows a couple of useful accessories like our HSC100 fast compass sensor which can be connected to the CLA1000 to provide Rate-of-Turn and vessel heading data for the AIS transmissions.  Also show is our Pilot Plug cable allowing connection of a PC or MAC to the CLA1000

What’s in the box?

This video is a little old, but we’ve been in the AIS business for a while which helps us support you better.  Here’s a video showing what’s included with the CLA1000

I know I have to get one but are there any advantages of installing an AIS?

Nobody likes a mandate with deadlines for installation but AIS genuinely improves navigation, safety and will make vessels more efficient for the future.  Unlike radar, AIS positively identifies a target with MMSI, callsign and name allowing communications to be quickly established.  The CLA1000 can also decode ATON (AIS aids to navigation) – these synthetic markers show on an AIS display but may not physically exist allowing dynamic management of the waterways.  AIS Personal SARTs are also available for MOB applications.  Additionally the AIS network can transmit information such as weather to mariners in real time.

iPad, MAC and PC Navigation

The CLA1000 is fitted with a pilot plug connector on the front of the display.  This allows GPS and AIS data to be connected to other devices either wirelessly (to an iPad or tablet using our WLN10HS NMEA to WiFi Server or PilotLink) or via a cable to a PC or MAC.  Digital Yacht has a great range of apps like NavLink US – a full featured charting and navigation program with detailed NOAA charts and a great AIS overlay including vessel scaling

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How do I get more information?

You can get further information on the CLA1000 from HERE

List price on the CLA1000 is $2799 but there’s amazing deals and offers for all commercial operators either through your local dealer or direct from us.  Contact us direct on 978 277 1234 to learn more and get instant savings today.

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.