COMPUTER-NETWORKS/Assignments/Lab 4/TECHNICAL_ANALYSIS.txt at main · Amey-Thakur/COMPUTER-NETWORKS · GitHub

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# LABORATORY TECHNICAL ANALYSIS: DYNAMIC HOST CONFIGURATION PROTOCOL (DHCP)
# ===============================================================
# Author: Amey Thakur
# GitHub: [Amey-Thakur](https://github.com/Amey-Thakur)
# Repository: [COMPUTER-NETWORKS](https://github.com/Amey-Thakur/COMPUTER-NETWORKS)
# Session: Fall 2023
# Release Date: November 01, 2023
# Lab 04: Analyzing Dynamic IP Allocation (DORA)
# --------------------------------------------------------------

INTRODUCTION:
This analysis explores the Dynamic Host Configuration Protocol (DHCP), which automates the assignment of IP addresses and network configuration to hosts. We focus on the four-step handshake known as DORA (Discover, Offer, Request, Acknowledgment).

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PART 1: THE DORA HANDSHAKE
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QUESTION 1: Identify the transport layer protocol used by DHCP.
- Protocol: UDP (User Datagram Protocol).
[EXPLANATION]: DHCP uses UDP ports 67 (Server) and 68 (Client) because it requires a lightweight, connectionless protocol that supports broadcasting before the client has an IP address.

QUESTION 2: What is the transaction ID in the DHCP messages?
- Transaction ID (XID): 0x74292ax (Example derived from trace).
[EXPLANATION]: This ID is generated by the client and remains constant across all stage of a single DORA handshake to ensure correct matching of messages.

QUESTION 3: At what Stage (1-4) does the client receive its IP address?
- Stage: Stage 4 (Acknowledgment).
[EXPLANATION]: While the Offer (Stage 2) proposes an IP, the allocation is only finalized when the server sends the ACK (Stage 4).

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PART 2: PROTOCOL METADATA
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QUESTION 5: What is the IP address of the DHCP server?
- Server IP: 192.168.2.1 (The local gateway).
[EXPLANATION]: This is the authoratative device managing the address pool for the local subnet.

QUESTION 6: What is the IP address offered to the client?
- Offered IP: 192.168.2.95.
[EXPLANATION]: This is the temporary logical identifier assigned to the client for the duration of the lease.

QUESTION 7: What is the lease time offered in the DHCP ACK?
- Lease Time: 259200 seconds (3 days).
[EXPLANATION]: This indicates how long the client can reliably use the IP address before needing to renew the allocation.

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TECHNICAL CONCLUSION:
Lab 04 demonstrates the elegance of DHCP in managing limited IP resources. The use of the Transaction ID and the DORA sequence enables robust, automated network setup, making modern plug-and-play networking possible.
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