Overview
This lecture explains the Transmission Control Protocol (TCP): its role in reliable network communication, core features, advantages, disadvantages, and how it works with the Internet Protocol (IP).
Introduction to TCP
- TCP is a connection-oriented protocol used for reliable communication over networks.
- It operates at the transport layer (Layer 4) of the OSI model, between the application and network layers.
- TCP works with IP to form the TCP/IP protocol suite for data transmission.
How TCP Works
- TCP breaks data into small packets (segments), reassembles them at the destination, and ensures intact delivery.
- A three-way handshake (SYN, SYN-ACK, ACK) is used to establish connections.
- A four-step process (FIN, ACK, FIN, ACK) is used for connection termination.
- Segment numbering and acknowledgments (ACKs) guarantee in-order and error-free delivery.
- TCP adapts the sending rate based on receiver buffer size to avoid overflow.
Features of TCP
- Uses a segment numbering system with unique byte and sequence numbers for tracking data.
- Ensures connection-oriented, ordered data transfer between sender and receiver.
- Full duplex communication allows simultaneous data flow in both directions.
- Flow control uses sliding windows to match the sender's rate to receiver capacity.
- Error control detects and manages corrupted, lost, and duplicate segments using checksums.
- Congestion control prevents network overload with algorithms like Slow Start and Fast Recovery.
Advantages of TCP
- Provides reliable, ordered, and error-checked data delivery.
- Includes flow control and automatic recovery mechanisms.
- Ensures data reaches the correct destination in order.
- Is widely implemented and supported by standards organizations.
Disadvantages of TCP
- Can be resource-intensive for small networks due to its size.
- Multiple layers may slow down data transmission speed.
- Only works within the TCP/IP protocol suite—not compatible with protocols like Bluetooth.
- Lacks major updates since initial development.
Key Terms & Definitions
- TCP (Transmission Control Protocol) — a reliable, connection-oriented transport protocol.
- OSI Model — a conceptual framework with seven networking layers, TCP sits at Layer 4.
- IP (Internet Protocol) — handles addressing and routing of packets across networks.
- Handshake — sequence of messages to set up and terminate TCP connections.
- Flow Control — regulates data transfer rate to prevent receiver overload.
- Congestion Control — manages network traffic to avoid congestion.
- Checksum — error-detection code in the TCP header.
Action Items / Next Steps
- Review TCP 3-way handshake and connection termination processes.
- Study TCP header fields and practice identifying key features in packet data.
- Read about congestion control algorithms for deeper understanding.