This gist demonstrates how to detect a network connection on a BrightSign, and only load the application if the network is available

networkdetect.brs

REM
REM
REM This code demonstrates how to detect a network configuration.
REM Read more: http://docs.brightsign.biz/display/DOC/roNetworkHotplug
REM
Sub Main()
  networkAvailable = false
  'Check ethernet
  nc = CreateObject("roNetworkConfiguration", 0)
  if type(nc) = "roNetworkConfiguration" then
    currentConfig = nc.GetCurrentConfig()
    if type(currentConfig) = "roAssociativeArray" then
      if currentConfig.ip4_address <> "" then
        networkAvailable = true
      endif
    endif
  endif
  nc = invalid
  'Check wifi
  nc = CreateObject("roNetworkConfiguration", 1)
  if type(nc) = "roNetworkConfiguration" then
    currentConfig = nc.GetCurrentConfig()
    if type(currentConfig) = "roAssociativeArray" then
      if currentConfig.ip4_address <> "" then
        networkAvailable = true
      endif
    endif
  endif
  mp = createObject("roMessagePort")
  hotPlug = createObject("roNetworkHotplug")
  hotPlug.setPort(mp)
  while true
    if networkAvailable = true then
      loadApplication()
    endif
    event = wait(0, mp)
    if type(event) = "roNetworkAttached"
      networkAvailable = true
    elseif type(event) = "roNetworkDetached"
      networkAvailable = false
    endif
  endwhile
End Sub

Sub loadAppliction()
  'Your loading code here
End Sub