Cisco Certified Network Associate (CCNA) Practice Exam

What is the port number used by TFTP?

1. 69

2. 53

3. 21

4. 161

The correct answer is: 69

The port number used by TFTP, or Trivial File Transfer Protocol, is 69. TFTP is a simple protocol used for transferring files between devices on a network, particularly useful in environments where a straightforward and lightweight transfer method is necessary, such as during the booting process of network devices or when configuring routers and switches. The choice of port 69 is standardized for TFTP communication, differentiating it from other protocols that use different port numbers such as DNS, which operates on port 53, FTP conventionally using port 21, and SNMP which uses port 161. Knowing the correct port number is essential for network configuration and troubleshooting, as it aids in understanding how various services interact over TCP/IP networks.