Using a conventional application port prevents a sender from placing that application's traffic on a different port number.

### Why this is right Port conventions help a receiving server map traffic to an application, but they do not prevent a sender from using another port. The statement confuses a convention with an enforcement mechanism. ### The concept A well-known port is commonly associated with a service. For example, the refresher identifies Transmission Control Protocol (TCP) port 443 with HTTPS and TCP port 22 with SSH. The receiving server can use the destination port to decide which application should process incoming traffic. However, a port number is not proof of what the traffic contains. The material notes that modern hardware firewalls can detect application traffic even when it is sent on a different port. ### The other options - **True**: This would be true only if the network enforced a restriction that blocked traffic using other ports. A port convention by itself does not do that. ### Terms - **TCP**: Transmission Control Protocol. A transport protocol that supports reliable delivery. - **HTTPS**: Hypertext Transfer Protocol Secure. Encrypted web traffic, listed with TCP port 443 in the refresher. - **SSH**: Secure Shell. A remote-access application, listed with TCP port 22 in the refresher. - **Port convention**: A commonly used association between a port number and an application. - **Destination port**: The transport port used by the receiving device to direct traffic to an application. - **Firewall**: A network security device that can inspect and control traffic. ### Remember A familiar port suggests an application, but the port number alone does not prove what the traffic is.