TCP does not perform packet fragmentation; this task is handled by the IP layer, specifically IPv4, when data packets exceed the network's MTU. TCP's main functions include the three-way handshake, sequencing, and acknowledgments.
The operation not performed by Transmission Control Protocol (TCP) is d. Packet fragmentation. TCP is responsible for ensuring that data is transmitted reliably across a network. It performs functions such as a three-way handshake to establish connections, sequencing to ensure data packets are organized in the correct order, and acknowledgments to confirm the receipt of data.
However, the process of breaking down data into smaller packets, known as packet fragmentation, is a task managed by the Internet Protocol (IP), specifically IPv4, when a packet is larger than the maximum transmission unit (MTU) of the network path.
Packet fragmentation occurs at the IP layer and is not a function of TCP, which operates at the transport layer, focusing on the reliable delivery of data rather than how it is split up or reassembled across the network infrastructure.