I have set up were a client PC site on a vehicle which travels with about 30 km/h. The vehicle then passes several access points. I have a camera on the vehicle which delivers images to a PC sitting wired behind the AP’s. The problem is when the client hop’s to the next AP (hand over) I loose a small amount of data which causes a frame drop in the video signal.
Dose anyone knows of a solution which can deal with this handover data loss. This can be a solution which is implemented on the router and on the server.
One way I could see having a smooth transistion without any dropped packets using this off-the-shelf technology is to use a multiple radio unit. When near the trade-off point the unit would have a connection to each AP. This way there is never a time where the camera is transmitting data but has nowhere to send it.
The other method would be buffering the data locally, this way even with a momentary drop the data is preserved.
The solution with multiple radios may work, say we configure one radio on channel 1 on the vehicle and at the start of the travel this radio is in use. The second radio on the vehicle is configured on channel 6, at half distance travelled this radio is now able to see the radio installed at the endpoint of the travel also operated at channel 6. How can I perform a fast switching from one radio to the other? What mechanism would make this decision to use the secondary pathway?
Thanks for your help
The video stream is used to control the vehicle so buffering will not work.
Set it up WDS. If you’ve got enough overlap, should roam fine.
My problem with roaming while streaming (not that I do much of that) is the IP addresses. At home, I can swap between my home AP, my brother’s home AP, or my tower on 2.4 or 5.
The snag is the IP address. Even roaming from one AP to the other, both connected to the same 100mb ethernet, DHCP client lags long enough for data loss. Set static, all is well.
Running on MT, the IP didn’t seem to be the issue until I swapped to another IP range entirely.
I don’t get the DHCP issue, are you running DHCP on every AP? Move DHCP to a single device and configure each router as a DHCP repeater. No more DHCP issues.