private System.Net.IPEndPoint BBMDSentAdd(Net.IPEndPoint BBMD, Net.IPAddress Mask)
{
byte[] bm = Mask.GetAddressBytes();
byte[] bip = BBMD.Address.GetAddressBytes();
/* annotation in Steve Karg bacnet stack :
*
* The B/IP address to which the Forwarded-NPDU message is
* sent is formed by inverting the broadcast distribution
* mask in the BDT entry and logically ORing it with the
* BBMD address of the same entry. This process
* produces either the directed broadcast address of the remote
* subnet or the unicast address of the BBMD on that subnet
* depending on the contents of the broadcast distribution
* mask.
*
* remark from me :
* for instance remote BBMD 192.168.0.1 - mask 255.255.255.255
* messages are forward directly to 192.168.0.1
* remote BBMD 192.168.0.1 - mask 255.255.255.0
* messages are forward to 192.168.0.255, ie certainly the local broadcast
* address, but these datagrams are generaly destroy by the final IP router
*/
for (int i = 0; i < bm.Length; i++)
{
bip[i] = (byte)(bip[i] | (~bm[i]));
}
return(new System.Net.IPEndPoint(new System.Net.IPAddress(bip), BBMD.Port));
}
// Used to initiate the BBMD & FD behaviour, if BBMD is null it start the FD activity only
public void AddBBMDPeer(Net.IPEndPoint BBMD, Net.IPAddress Mask)
{
BBMD_FD_ServiceActivated = true;
if (BBMD != null)
{
lock (BBMDs)
BBMDs.Add(new KeyValuePair <System.Net.IPEndPoint, System.Net.IPAddress>(BBMD, Mask));
}
}
