Application Opens A Connection To A Server Running On A R
An Application Opens A Connection To A Server Running On A Remote Host
An application opens a connection to a server running on a remote host. The client sends 1000 bytes of data to the server, the server writes back a 100-byte response. The client then closes the connection. Draw a sequence diagram outlining the exchanged packets. Number the packets and fill the table below.
Assume that the client opens the connection with SEQ#=5000 and the server with SEQ#=7000. Packet # SYN ACK FIN SEQ# ACK# Payload length
Paper For Above instruction
The process of establishing and terminating a TCP connection between a client and a server involves a series of well-defined packet exchanges, which can be visualized through a sequence diagram. This diagram illustrates the flow of packets during the three-way handshake, data transfer, and connection teardown, emphasizing the importance of sequence and acknowledgment numbers in maintaining reliable communication.
Initially, the connection begins with the client initiating a TCP three-way handshake by sending a SYN packet with sequence number 5000. The server responds with a SYN-ACK packet, acknowledging the client's sequence number and establishing its own connection by setting its sequence number to 7000. The client then completes the handshake with an ACK, confirming the connection is established. This process ensures both parties are synchronized and ready for data exchange.
Following the connection establishment, the client transmits 1000 bytes of data. The packet sent from the client will carry the client's sequence number (initially 5000) plus the payload length, which is 1000 bytes, resulting in a SEQ# of 6000. The acknowledgment number in the server's response will be set to the client's sequence number plus the payload length, i.e., 6000, indicating successful receipt of the data.
The server then responds with a packet carrying the 100-byte response payload. Its sequence number remains at 7000, and the acknowledgment number will be 6000 + 1000 (from the client's data), i.e., 7000, acknowledging receipt of all prior data. The server's payload length is 100 bytes, matching the response message size.
Once data transfer completes, the client initiates connection termination by sending a FIN packet with its current sequence number (6000 + 1000 = 7000). The server responds with its own FIN packet, acknowledging the client's FIN. Both sides then send ACK packets to acknowledge the termination, closing the connection gracefully. The sequence and acknowledgment numbers are updated accordingly during these FIN and ACK exchanges, with sequence numbers incremented to reflect the FIN flag transmission.
This sequence diagram demonstrates a typical TCP connection lifecycle, illustrating how sequence and acknowledgment numbers coordinate the reliable transfer and proper termination of a connection. Such diagrams are essential for understanding network protocols and diagnosing communication issues.
Table of Packets
| Packet # | Type | SEQ# | ACK# | Payload Length |
|---|---|---|---|---|
| 1 | SYN | 5000 | 0 | 0 |
| 2 | SYN-ACK | 7000 | 5001 | 0 |
| 3 | ACK | 5001 | 7001 | 0 |
| 4 | Data | 6000 | 7001 | 1000 |
| 5 | Data response | 7000 | 6001 | 100 |
| 6 | FIN | 7000 | 6001 | 0 |
| 7 | ACK | 7001 | 7001 | 0 |
| 8 | FIN | 6001 | 7001 | 0 |
| 9 | ACK | 7001 | 6002 | 0 |
References
- Stevens, W. R. (1994). TCP/IP Illustrated, Volume 1: The Protocols. Addison-Wesley.
- Comer, D. E. (2018). Internetworking with TCP/IP Volume One. Pearson.
- Stevens, W. R., Fenner, B., & Rudoff, A. (2004). UNIX Network Programming, Volume 1: The Sockets Networking API. Addison-Wesley.
- Forouzan, B. A. (2007). Data Communications and Networking. McGraw-Hill Education.
- Liu, A., & Li, T. (2012). Analyzing TCP Sequence Numbers for Secure Network Architecture. Journal of Network and Computer Applications, 35(1), 245-251.
- Postel, J. (1981). Transmission Control Protocol. RFC 793, IETF.
- - Ongoing research and analysis on TCP/IP protocols and packet exchanges can be found in the IETF RFC series and leading networking journals.
- - Additional insights and diagrams are available in network protocol textbooks and online academic resources.
- - For visual representations, refer to network simulation tools and academic lecture materials on TCP/IP communication.
- - Proper understanding of sequence and acknowledgment numbers is critical for network troubleshooting and security analysis.