how to setup a wireshark capture filter for udp ports

Observe the packet details in the middle Wireshark packet details pane.

Select the first DNS packet, labeled Standard query.

To view only UDP traffic related to the DHCP renewal, type udp.port = 53 (lower case) in the Filter box and press Enter.

Observe the traffic captured in the top Wireshark packet list pane.Notice that it is bootpc (68), the bootp client port.Īctivity 3 - Analyze UDP DNS Traffic Notice that it is bootps (67), the bootp server port. Notice that the destination address is your IP address. Notice that the source address is the DHCP server IP address. The destination should be your MAC address and the source should be your DHCP server's MAC address. Observe the Destination and Source fields.In the top Wireshark packet list pane, select the second DHCP packet, labeled DHCP ACK.

Notice that it is bootpc (68), the bootp client port. Expand User Datagram Protocol to view UDP details.Notice that the destination address is the DHCP server IP address. Notice that the source address is your IP address. Expand Internet Protocol Version 4 to view IP details.The destination should be your DHCP server's MAC address and the source should be your MAC address. Expand Ethernet II to view Ethernet details.Notice that it is an Ethernet II / Internet Protocol Version 4 / User Datagram Protocol / Bootstrap Protocol frame. Select the first DHCP packet, labeled DHCP Request.To view only UDP traffic related to the DHCP renewal, type udp.port = 68 (lower case) in the Filter box and press Enter.

Type nslookup 8.8.8.8 and press Enter to look up the hostname for IP address 8.8.8.8.Īctivity 2 - Analyze UDP DHCP Traffic.

Type ipconfig /flushdns and press Enter to clear your DNS name cache.

If you have a static address, this will not generate any UDP traffic.

Type ipconfig /renew and press Enter to renew your DHCP assigned IP address.

These activities will show you how to use Wireshark to capture and analyze User Datagram Protocol (UDP) traffic.Īctivity 1 - Capture UDP Traffic Wireshark is a free and open source packet analyzer used for network troubleshooting and analysis.

4 Activity 2 - Analyze UDP DHCP Traffic.

How to setup a wireshark capture filter for udp ports