An organization is deploying an in-house real-time voice communications protocol across their WAN links. The network team recommends using User Datagram Protocol (UDP) instead of Transmission Control Protocol (TCP) for the media transport path. Which fundamental Layer 4 header property supports this recommendation by minimizing protocol overhead for delay-sensitive traffic?
- UDP utilizes a fixed header size of 8 bytes, whereas TCP requires a minimum header size of 20 bytes.Answer
- BUDP provides sequence number fields in its header to reorder voice packets without requesting retransmissions.
- CUDP includes dynamic windowing fields in its header to prevent buffer overflows during network congestion.
- DUDP executes a simplified 2-way handshake in its header to establish session state prior to transmission.
Answer
UDP utilizes a fixed header size of 8 bytes, whereas TCP requires a minimum header size of 20 bytes.
The correct answer highlights that UDP maintains a fixed header size of only 8 bytes (comprising Source Port, Destination Port, Length, and Checksum). In contrast, a TCP header has a minimum size of 20 bytes and can expand up to 60 bytes with options. For small real-time voice payloads sent at high packet rates, reducing Layer 4 header overhead from 20 bytes to 8 bytes significantly decreases network bandwidth consumption and latency.
Step-by-Step Solution
Key Concept
TCP vs UDP Header Overhead and Protocol Mechanics