How do Time Servers (NTP and HTTP) work on BrightSign players?

When I go to your time server ( http://time.brightsignnetwork.com/) there is just a reference to an image. 

I Would like to know how this works because we have a lan that is not connected to the internet, but one Server will be. We would like it to serve pages to the internal lan with things like weather and time etc.

Is the time somehow in this image?

Is there something else I should do other than using a php script to file_get_contents(" http://time.brightsignnetwork.com/") and echo it out to the client?

The unit must have Internet access in order to sync the time with the brightsign timeserver. You can point the unit to a different time server when creating setup files (Tools - Setup BrightSign Unit).

So what is the format of the time signal? Is BrightSigns expecting the unix epoch time code in a string? is it SNTP? Or NTP?

Sorry... I Didn't look above... I see that it is NTP... I will give that a try.

You have provisions to connect a GPS device to a USB port for geofencing. Is there a way to set the time using the GPS NEMA data stream time/date value? If not, inherent, can it be done with a script?

i was able to achieve time synchronization with a web server running on my LAN and 'cut out' our brightsigns' requests for http://time.brightsignnetwork.com/  (the project i'm currently working on requires an entirely 'closed' network, so any/all 'outside' requests are undesirable)

as it turns out, all the units expect is an HTTP 200 OK and a response that contains a valid Date header, such as:

Date: Wed, 18 Jan 2023 16:55:25 GMT

you only need to execute the following bits of BrightScript once:

systemTime = CreateObject( "roSystemTime" )
systemTime.SetTimeZone( "EST" )

where the time zone is whatever you prefer, and:

netCfg = CreateObject( "roNetworkConfiguration", 0 )
netCfg.SetTimeServer( "http://192.168.0.2" )
netCfg.SetTimeServerIntervalSeconds( 300 )
netCfg.Apply()

where the wired configuration is assumed (0), the url is the server running on your LAN (or elsewhere) and the interval is of your choosing (the above is 5 minutes)

for completeness sake, also execute this once:

regSection = CreateObject( "roRegistrySection", "networking" )
regSection.Write( "ts", "http://192.168.0.2" )
regSection.Write( "tz", "EST" )
regSection.Flush()

do note that modifying the registry but not the network configuration doesn't "do it" and the unit(s) will continue to attempt requests at the default time server.

i confirmed it is working as expected by inspecting the log via diagnostic web server, setting the system time on my web server, waiting 5 minutes, seeing the change to the 'wrong' time, and back again.

per the above example, you'd see a line in the log that states:

NetworkTime: server changed to 'http://192.168.0.2'

as an additional check, i added a monitor for 'roNetworkTimeEvent' in my custom autorun.brs and the event object .WasSuccessful() method returns True, and the event is fired at the specified interval. you can do this yourself with something like:

msgPort = CreateObject( "roMessagePort" )

sysTime = CreateObject( "roSystemTime" )
sysTime.SetPort( msgPort )

while True
    msgEvent = msgPort.WaitMessage( 10000 )
    if type( msgEvent ) = "roNetworkTimeEvent" then
        isOK = "no"
        if msgEvent.WasSuccessful() then
            isOK = "yes"
        endif
        REM do something useful here to indicate status
    endif
end while