In an IP network, which field helps computers reorder packets that arrive out of order?

In an IP network, which field helps computers reorder packets that arrive out of order?

• A. Destination port
• B. Sequence number
• C. Time to Live
• D. Source IP address

Answer: (B)

Packets can take different paths and arrive in a different order than they were sent. To rebuild the original data stream, each piece carries a position marker—the sequence number. The receiving system uses these numbers to place segments in the correct order and to detect any missing pieces, buffering as needed until the data can be opened in the right sequence. That sequencing is what makes the data flow seamless for the application. Other fields serve different roles: the destination port directs the data to the right application, Time to Live helps prevent looping in the network, and the source IP identifies who sent the packet. These don’t provide the ordering information needed to reorder arriving packets.

Packets can take different paths and arrive in a different order than they were sent. To rebuild the original data stream, each piece carries a position marker—the sequence number. The receiving system uses these numbers to place segments in the correct order and to detect any missing pieces, buffering as needed until the data can be opened in the right sequence. That sequencing is what makes the data flow seamless for the application.

Other fields serve different roles: the destination port directs the data to the right application, Time to Live helps prevent looping in the network, and the source IP identifies who sent the packet. These don’t provide the ordering information needed to reorder arriving packets.