How to Ping a UDP Port
Ping is a command that reaches out and asks the intended recipient if it is there and waits for an answer. The intention of this is to make sure the recipient is there and to measure the amount of time that it takes to get a response. Ping is a good utility to measure round trip delay if users report network slowness. One issue with the original ping utility is that it was only intended to use Transmission Control Protocol, or TCP. This has since been adapted to tests that include User Datagram Protocol, or UDP, so that you can simulate traffic for programs that use strictly UDP to run.
Open the program. Network MAPper (Nmap) is a utility that is used to scan open ports and end devices. This utility has a front end graphical user interface for windows called Zenmap. This is not a standard program that is preinstalled with windows but can be downloaded for free from the nmap website. This utility requires an additional file called WinPcap, which can only be installed by a person with administrative permissions on the computer.
Enter the Internet protocol, or IP, address of the target in the field marked target. This is the IP address that you are trying to reach or the receiver of the UDP packet. Start with one IP, but as you learn to use the utility you can scan a whole group of IPs at a time.
Enter the command in the command box. There are many different commands that this utility can perform but for this instance we will use the following command to indicate a UDP scan is what is wanted."nmap -sU 192.168.1.1"The IP in this command should be replaced with your intended target. Then click "Scan."
Recover the needed information from the scan window below. This scan includes 1,000 of the more common reports and the system will report back on each port. The port will appear to be in one of six states. The closed state is where a port needs to be sitting to be available for an attack. Scanning your own computer and or devices will allow you to discover where you are most exposed.
Tips & Warnings
- Update your copy of Zenmap to get all the new features and options for additional scans, bug repairs and updates.
- Scan your computer and devices often to keep tight security on your network and close any open doors before an hacker uses the opportunity to attack.
References & Resources
- "Data and Computer Network Communication"; Shashi Banzal; 2007
- "CCNA Cisco Certified Network Associate Study Guide (Exam 640-802)"; Richard Deal; 2008
- "TCP/IP Sockets in C: Practical Guide for Programmers, Second Edition"; Michael Donahoo, et al.; 2009
- "Hacking Exposed 6: Network Security Secrets and Solutions"; Stuart McClure, et al.; 2009
- Cisco: TCP and UDP Small Servers
- Cisco: Understanding the Ping and Traceroute Commands