furuno FA-30 ais messages not being picked up by openCPN

[barnakiel]

Originally Posted by bobbylockes

(...) and sent it using my wireless network adapter address 192.168.178.15 to 192.168.178.7 on port 10034 (wireless adpater has submask 255.255.255.0). These !AIVDM messages that my program is forwarding as a UDP packet are indeed picked up by wireshark but despite configuring OpenCPN to 192.168.178.7 listening on port 10034 openCPN is STILL RECEVING NO MESSAGES!!!

(...)

any advice welcome.

Specify the talker IP, not the listener IP in the OpenCPN net interface.

You are sending from 192.168.178.15 to 192.168.178.7 THEN OpenCPN net port should be listening to 192.168.178.15.

Unless the UDP is so different from TCP that you indeed listen to the listener. Odd, but not impossible.

barnakiel

[barnakiel]

Originally Posted by bobbylockes

I GOT IT TO WORK!!!!!

(...)

what is packetsender doing that allows the java and opencpn to suddenly start receiving messages?!?!!? mmmmmm

(...)

CONGRATS!

PHP / java / C may be handling the nulls differently - then a piece of software in between your FA-30 and OpenCPN may in fact be dropping the nulls which gives you what the OpenCPN accidentally expects.

So I am not firing up that kplex router after all.

Well done. Where there is will, there is way.

Cheers,
b.

[did-g]

Originally Posted by bobbylockes

any idea why this only worked when I chose x.x.255.255 and x.x.x.255. this whole process doesnt't work if id dont use 255 in the ipaddress AND manuallyfire off a pcket with pacjet sender to said ip address?

windows firewalk as opened for 10033.

sounds something like this... Can't receive udp packets

Did you try with 127.0.0.1?
For testing you can disable the firewall , common causes for this kind of behavior are
- a firewall, with most of them sending a UDP packet to a IP port open the door.
- weird ARP issue but it's very unlikely on the same computer.

for the 255 ? I don't know windows very well and there's a lot of knobs but 255 are broadcast ip for /24 /16 /8 networks and it's possible windows doesn't use the same rules for broadcast, ie processes on the same computer don't see unicast packets only broadcast packets.

[bobbylockes]

Originally Posted by barnakiel

CONGRATS!

PHP / java / C may be handling the nulls differently - then a piece of software in between your FA-30 and OpenCPN may in fact be dropping the nulls which gives you what the OpenCPN accidentally expects.

So I am not firing up that kplex router after all.

Well done. Where there is will, there is way.

Cheers,
b.

Hi thanks!! And thanks for the help.

I wrote my java programto strip away the nulls. Then it broadcasts the clean aivdm messgaes on a differemt port also from woreless network card ipaddress and not ethernet (not sure whether thats signoficant, i did try broadcasting it on the differemt port from 172,31,24,7 but didnt get picked up by opencpn only wireshark). As didg states this could be the windows firewall.

[bobbylockes]

Originally Posted by did-g

Did you try with 127.0.0.1?
For testing you can disable the firewall , common causes for this kind of behavior are
- a firewall, with most of them sending a UDP packet to a IP port open the door.

yup. disabling it on "public network" caused messages to stream into my java and opencpn

Now trying to get this to work through wireless router instead of directly, whilst still being able to use the internet. I assume if I force an ipaddress 172.31.x.x on my wirrelss network card that I won't be able to surf the net.

[bobbylockes]

Originally Posted by did-g

Did you try with 127.0.0.1?
For testing you can disable the firewall , common causes for this kind of behavior are
- a firewall, with most of them sending a UDP packet to a IP port open the door.
- weird ARP issue but it's very unlikely on the same computer.

for the 255 ? I don't know windows very well and there's a lot of knobs but 255 are broadcast ip for /24 /16 /8 networks and it's possible windows doesn't use the same rules for broadcast, ie processes on the same computer don't see unicast packets only broadcast packets.

no haven't tried with 127.0.0.1 yet

Originally Posted by did-g

Did you try with 127.0.0.1?
For testing you can disable the firewall , common causes for this kind of behavior are
- a firewall, with most of them sending a UDP packet to a IP port open the door.

yup. disabling "public network" firewall caused messages to stream into my java and opencpn with any need for packersender!

Now trying to get this to work through wireless router instead of direct ethernet connection whilst still being able to use the internet. I've got it to work through wireless router when I manually assign my laptop top 172.31.24.x but then lose my internet connection. I guess the router won't except my laptops ip anymore. so two questions that google won't give me answers to
Can i configure my router to forward udp messages received from the furuno ais 172.31.24.2 to a 192.168 address? instead of what it currently is doing broadcasting to 172.31.255.255 and expecting a submask of 255.255.0.0?

or can I somehow configure my laptop not only to have a 172.31.*.* address but also still have it accepted by my router.

router configuration seems limited to port forwarding and I don't think thats what I want here.

[bobbylockes]

Originally Posted by did-g

Hi
it's a known issue, there's ascii null in Furuno data header (you can see them in your first screenshot, in the data hexa dump).

it currently doesn't work with opencpn.

Having now fixed it using a small udp server written in java, it would be very easy for opencpn developers to fix it too. just stripping everything in the furuno message before "!" in the message, and make sure the firewall on the laptop is disabled or perhsps have opencpn send a quick test packet to itself after udp config for ais in opencpn has been congiured by the user. I'll do it.

[muttnik]

Originally Posted by bobbylockes

Can i configure my router to forward udp messages received from the furuno ais 172.31.24.2 to a 192.168 address? instead of what it currently is doing broadcasting to 172.31.255.255 and expecting a submask of 255.255.0.0?

or can I somehow configure my laptop not only to have a 172.31.*.* address but also still have it accepted by my router.

The 3 obvious options are:
1. Change the FA-30's address and netmask to be on your 192.168.178/24 network. Ideally you want to make sure the address you assign it is not in the range your router hands out via dhcp to things connecting to the network (check your router manual). Don't forget to change the netmask to 255.255.255.0
2. Configure a secondary interface on your laptop's wireless interface and assign it a 172.31.x.x address with a net mask of 255.255.0.0. Someone Windows savvy could talk you through that one. Nothing wrong with having two lIP networks on the same medium.
3. Change the router's configuration so that it has an address on the 172.31.x.x network and hands out dynamic addresses on that network, ideally excluding 172.31.24.2

[bcn]

Originally Posted by bobbylockes

Having now fixed it using a small udp server written in java, it would be very easy for opencpn developers to fix it too. just stripping everything in the furuno message before "!" in the message, and make sure the firewall on the laptop is disabled or perhsps have opencpn send a quick test packet to itself after udp config for ais in opencpn has been congiured by the user. I'll do it.

In case this issue gets addressed please remember the short discussion about IEC61162-450 we had here several weeks before. This is NMEA0183 over IP4, or LightWeightEthernet (LWE)
https://en.wikipedia.org/wiki/IEC_61162

The implementation should be IEC61162 compliant, at least as listener. Asking for an IEC61162-450 data provider from within OCPN seems perhaps much to ask..

Hubert

[bobbylockes]

Originally Posted by muttnik

The 3 obvious options are:
1. Change the FA-30's address and netmask to be on your 192.168.178/24 network. Ideally you want to make sure the address you assign it is not in the range your router hands out via dhcp to things connecting to the network (check your router manual). Don't forget to change the netmask to 255.255.255.0

how do I change that? it seems to be hardcoded in furuno, the router its now attached to doesnt assign it an ipaddress?

2. Configure a secondary interface on your laptop's wireless interface and assign it a 172.31.x.x address with a net mask of 255.255.0.0. Someone Windows savvy could talk you through that one. Nothing wrong with having two lIP networks on the same medium.

seems the only software option available

3. Change the router's configuration so that it has an address on the 172.31.x.x network and hands out dynamic addresses on that network, ideally excluding 172.31.24.2

not sure the routers (from my internet provider#) gui allows me to do this. I could only find config for port forwarding and security . I could attach it to a second wireless router I've once bought myself and tryto configure that..

thanks

[muttnik]

Originally Posted by bobbylockes

how do I change that? it seems to be hardcoded in furuno, the router its now attached to doesnt assign it an ipaddress?

The Fine Manual seems to have instructions under "COM port setup, Network setup" if this is indeed the device you have:

https://www.furunousa.com/ProductDoc...%209-21-07.pdf

[bobbylockes]

Originally Posted by muttnik

The Fine Manual seems to have instructions under "COM port setup, Network setup" if this is indeed the device you have:

https://www.furunousa.com/ProductDoc...%209-21-07.pdf

thanks. btw notice the com port is with the powerlead. On mine only the powerleads are visible, which is why I thought it only had an ethernet port.

[bobbylockes]

Yup. Mine second hand o e just hadnred and black wire for power hence i was mistaken. My fa3 is missing the ra 422

[bobbylockes]

Originally Posted by muttnik

The Fine Manual seems to have instructions under "COM port setup, Network setup" if this is indeed the device you have:

https://www.furunousa.com/ProductDoc...%209-21-07.pdf

great...thanks for posting the manual. Handy web interface for furuno ais did the trick. I changed furunos ip address from the defaul 172.31.24.2 to 192.168.178.2 and submask from 255.255.0.0 to 255.255.255.0 and now I've got internet and ais data through my wireless router . I kept the default port furuno fa-30 is configured to as 10000. The strange thing is that its broadcasting on 10033 though (as picked up by wireshark - what a fantastic piece of software wireshark is for re-engineering stuff) - so why is the default port 10000? wierd.

[BlueDefendr]

Yes, I'm *that guy* who is resurrecting a four year old thread.

@bobbylockes - I'm hoping you are still around and still have that FA-30

I'm working on a related project, and this post is full of gold to help me on my way. Basically what I'm trying to do is take a Raspberry Pi with a dAISy AIS receiver and effectively emulate an FA-30 on the network. I'd like my device to be able to emit the UDP packet that can be received by my NavNet VX-2 to show targets on the screen.

To do this, I believe from reading this thread I need to do the reverse of what bobby was trying to do. Instead of stripping of the Furuno specific pre-amble on the UDP packets and emitting only the ASCII AIS sentences, I need to take a source of AIS sentences and wrap them up with the Furuno preamble so that the NavNet sees the data it expects.

Bobby - I'm hoping you'd be willing to (or still have) share some more wireshark traces of an actual FA-30 conversation - the more the better, so that I can try and reverse engineer the preamble format (assuming it's not static - and somehow a function of the included sentences).