In terms of security, what is a key feature of a sallyport?

A sallyport is designed specifically to control access and enhance security in facilities such as prisons or secure buildings. One of its key features is that only one gate opens at a time. This design ensures that when a vehicle or individual enters or exits through one gate, the other remains closed, which prevents unauthorized access and enhances overall security. This sequential operation minimizes the risk of escape or breach, as it limits the number of individuals who can enter or exit the secured area simultaneously.

In a sallyport, the controlled opening and closing of gates are crucial for maintaining safety and security protocols, which is why this feature is integral to its function. The other options do not accurately reflect the purpose of a sallyport, as unrestricted access and public openness would compromise security, and while surveillance cameras can enhance security, they are not defining features of a sallyport itself.