Учет трафика

private static void ShowNetworkTraffic()
{
    PerformanceCounterCategory performanceCounterCategory = new PerformanceCounterCategory("Network Interface");
    string instance = performanceCounterCategory.GetInstanceNames()[0]; // 1st NIC !
    PerformanceCounter performanceCounterSent = new PerformanceCounter("Network Interface", "Bytes Sent/sec", instance);
    PerformanceCounter performanceCounterReceived = new PerformanceCounter("Network Interface", "Bytes Received/sec", instance);
 
    for (int i = 0; i < 10; i++)
    {
        Console.WriteLine("bytes sent: {0}k\tbytes received: {1}k", performanceCounterSent.NextValue() / 1024, performanceCounterReceived.NextValue() / 1024);
        Thread.Sleep(500);
    }
}

string instance = performanceCounterCategory.GetInstanceNames()[2];

PerformanceCounterCategory performanceCounterCategory = new PerformanceCounterCategory("Network interface");           
           
            string instance = performanceCounterCategory.GetInstanceNames()[1]; 
            //string instance = "WAN [PPP_SLIP] Interface"; //либо так
            PerformanceCounter performanceCounterSent = new PerformanceCounter("Network Interface", "Bytes Sent/sec", instance);
            PerformanceCounter performanceCounterReceived = new PerformanceCounter("Network Interface", "Bytes Received/sec", instance);
 
            for (int i = 0; i < 1000; i++)
            {
                Console.WriteLine("bytes sent: {0}k\tbytes received: {1}k", performanceCounterSent.NextValue()/1024 , performanceCounterReceived.NextValue()/1024);
                Thread.Sleep(500);
            }