public static int NbServerConn()
{
return knownChains.Count(row => row.Side == ChainSide.SERVER_CONN && row[0] is TcpReceiver);
/*lock (lockChainManagement)
{
return knownChains.Count(row => row.Side == ChainSide.SERVER_CONN && row[0] is TcpReceiver);
}*/
}