Which protocol defines how frames are routed through a fast-packet network based on the address field in the frame?

• A. Frame relay
• B. Full Backup
• C. Fully Qualified Domain Name (FQDN)
• D. Grey-Box Testing

Answer: (A)

This question is about how frames are routed in a fast-packet network based on the address field in the frame. Frame Relay is designed for WANs where routing decisions are made at the data-link layer using an address in each frame header—the DLCI, which identifies the virtual circuit the frame belongs to. Switches in the Frame Relay network read this address and forward the frame accordingly, enabling efficient, rapid switching across a network with many possible paths.

The other terms don’t define how frames are routed in this way. A full backup is about data protection and recovery, not frame routing. A fully qualified domain name is a DNS naming scheme for hosts, not a frame-addressing method. Grey-box testing is a testing approach, not a network routing protocol.