slow response time

[xeron333]

I'm using SharpPCap, but I'm still having the problem of slow response times between the HTTP request and the display of the corresponding packet, sometimes lasting several minutes. Therefore, I can't use SharpPCap for real-time analysis. However, I changed the settings when opening the IliveDevice interface. Here's the code managing the IliveDevice settings:

DeviceConfiguration config=new DeviceConfiguration();
config.Immediate = true;

and...

int readTimeoutMilliseconds = 1000;
deviceC.Open(mode: DeviceModes.MaxResponsiveness | DeviceModes.MaxResponsiveness | DeviceModes.MaxResponsiveness, read_timeout: readTimeoutMilliseconds);
deviceC.Open(config);

[kayoub5]

Do you experience same issue with Wireshark?

Such delays usually means your application is taking too long to process packets, thus the Libpcap queue is getting full.

[xeron333]

Thanks
I don't use Wireshark. Do you need my entire application code to see where the problem is coming from?

[kayoub5]

Do you performance issues when using the example applications?

[xeron333]

Hello and thank you.
I tried BasicCap Example 3:
https://github.com/dotpcap/sharppcap/blob/master/Examples/Example3.BasicCap/Program.cs

I see where the problem lies: the program slows down when querying the DNS. I want to know the hostname :

var packet = PacketDotNet.Packet.ParsePacket(rawPacket.LinkLayerType, rawPacket.Data);
var tcpPacket = packet.Extract<PacketDotNet.TcpPacket>();
if (tcpPacket != null)
{
var ipPacket = (PacketDotNet.IPPacket)tcpPacket.ParentPacket;
System.Net.IPAddress srcIp = ipPacket.SourceAddress;
System.Net.IPAddress dstIp = ipPacket.DestinationAddress;
int srcPort = tcpPacket.SourcePort;
int dstPort = tcpPacket.DestinationPort;
IPHostEntry hostSource;
string hSrc_ch=null;
IPHostEntry hostDest;
string hDest_ch=null;
//It is from these lines that the program slows down:
try
{
hostSource = Dns.GetHostEntry(srcIp);
hSrc_ch = (string)hostSource.HostName;
hostDest = Dns.GetHostEntry(dstIp);
hDest_ch = (string)hostDest.HostName;
}
catch (Exception e0)
{
Console.WriteLine("--Hôte Inconnu ! " + e0.Message);
}
}

Do you know how to speed up the DNS query?

[kayoub5]

Look at the HTTP URL instead of doing DNS to find the hostname

[kayoub5]

Not a sharppcap issue, closing