Yes, TCP does have error detection.
TCP, or Transmission Control Protocol, is designed to provide reliable data delivery. A key component of ensuring reliability is the ability to detect errors that may occur during transmission across an IP network.
TCP Error Detection Explained
According to the reference: "TCP provides reliable, ordered, and error-checked delivery of a stream of octets (bytes) between applications running on hosts communicating via an IP network."
This highlights that error detection, or "error-checked delivery", is an inherent part of the TCP protocol's functionality. This means that TCP includes mechanisms to verify the integrity of the data being transmitted.
How TCP Detects Errors
While the reference doesn't detail how TCP detects errors, it's important to know some core concepts:
- Checksum: TCP uses a checksum field in its header. The sending TCP calculates a checksum value based on the data being sent. The receiving TCP then recalculates the checksum upon receiving the data. If the calculated checksum does not match the checksum in the TCP header, the receiving TCP knows that an error occurred during transmission and discards the segment.
- Retransmission: Error detection is coupled with retransmission. If an error is detected (e.g., checksum failure), the receiving TCP will not acknowledge receipt of the data. The sending TCP, after a timeout period, will retransmit the unacknowledged data.
The Importance of Error Detection in TCP
- Data Integrity: Ensures the data received is identical to the data sent.
- Reliable Communication: Contributes to the overall reliability of TCP, which is crucial for many applications.
- Foundation for Applications: Applications can rely on TCP to handle error detection and correction, freeing them from having to implement their own error-handling mechanisms.
