Transmission control protocol is:

Question

Accepted Answer

The correct option is (4):
The Transmission Control Protocol (TCP) is fundamentally defined as a **Connection Oriented Protocol**. Operating at the Transport Layer of the TCP/IP model, TCP requires a specific, explicit procedure known as the "three-way handshake" (SYN, SYN-ACK, ACK) to establish a stable, logical end-to-end connection between the sending and receiving applications *before* any application data transfer begins. Once this virtual circuit is established, TCP uses sequence numbers, acknowledgments (ACKs), retransmission timers, and flow control mechanisms to guarantee the reliable, ordered, and error-checked delivery of the byte stream. This reliable, session-based connection is a core feature of TCP, making it essential for applications where data integrity is paramount, such as web browsing (HTTP), email (SMTP), and file transfer (FTP).

The incorrect option is (1):
The term "Collision sensitive protocol" is not a standard classification for a Transport Layer protocol like TCP. Collision detection and handling are low-level concerns that belong to the Data Link (Layer 2) and Physical (Layer 1) layers of the network stack. Protocols such as CSMA/CD, which is used by traditional Ethernet, are designed to detect and manage physical-level collisions on a shared medium. TCP operates on a host-to-host basis *above* these layers; therefore, it does not directly deal with the issue of data collisions on the physical cable.

The incorrect option is (2):
Similarly, possessing a "Collision less property" is a characteristic of certain Layer 2 access methods, such as CSMA/CA used in wireless networks, or Token Ring, where the access method is designed to avoid simultaneous transmissions on the medium. Like collision sensitivity, this property is far removed from the Transport Layer where TCP resides. TCP is concerned with the logical flow of data between applications, ensuring all segments arrive correctly and in order, regardless of the collision status of the underlying physical network.

The incorrect option is (3):
The classification **Connection less protocol** is the direct antithesis of TCP and correctly describes the User Datagram Protocol (UDP). Connectionless protocols, like UDP, send data in independent units (datagrams) without establishing a handshake or maintaining a dedicated session. This makes them faster but inherently unreliable, as they offer no built-in mechanisms for guaranteeing delivery, sequence ordering, or error correction. TCP, by contrast, is a heavyweight protocol that prioritizes absolute reliability over speed, explicitly by being connection-oriented.