When preparing for Cisco networking exams or other IT certifications, understanding how fundamental protocols operate is essential. The 21.2.12 lab - examining telnet and ssh in Wireshark is a practical lab designed to help learners analyze the differences between Telnet and SSH using packet capture tools like Wireshark. This guide from DumpsQueen Official will walk you through every step, break down key packet details, and highlight security implications—making it perfect for anyone using Exam Prep Dumps and Study Guide material.
Whether you're a networking student, IT professional, or certification aspirant, this blog will enhance your protocol analysis skills and deepen your knowledge of terminal communication over a network.
Understanding Telnet and SSH
Before diving into packet analysis, it's crucial to grasp what Telnet and SSH are.
- Telnet is an older, text-based protocol used to manage devices remotely over a network. It transmits all data—including login credentials—in plaintext, which poses a significant security risk.
- SSH (Secure Shell) is the secure alternative to Telnet. It encrypts all data, including usernames and passwords, offering a far safer method of remote administration.
Both protocols are widely covered in network certification exams, and labs like 21.2.12 lab - examining telnet and ssh in wireshark provide the hands-on experience needed for mastering this knowledge.
What Is Wireshark and Why Is It Used in This Lab?
Wireshark is an open-source packet analyzer that captures and displays network traffic in real time. It’s widely used for troubleshooting, protocol development, and educational purposes. In this lab, Wireshark allows you to view the exact differences in how Telnet and SSH communicate over the network.
Wireshark helps learners:
- Identify communication protocols
- Examine packet structures
- Observe security mechanisms in action
- Understand the importance of encrypted vs. unencrypted data
Lab Setup: Tools Required
To complete the 21.2.12 lab - examining telnet and ssh in wireshark, you will need:
- Two virtual machines (or physical computers) running a Linux distribution or Cisco Packet Tracer environment
- Wireshark installed on the machine where packets will be captured
- Network access between the two devices
- Telnet and SSH services enabled and configured
Step-by-Step Guide to the 21.2.12 Lab
1. Start Wireshark Capture
Open Wireshark and start a packet capture on the active network interface. Filter by port if necessary:
- For Telnet: tcp.port == 23
- For SSH: tcp.port == 22
2. Initiate Telnet Session
Open a terminal on the client machine and connect to the server via Telnet:
css
telnet [IP Address]
Log in with the username and password. Observe the packets being captured in Wireshark.
3. Analyze Telnet Traffic in Wireshark
Stop the capture and examine the packet details:
- Expand the TCP payload
- Read the transmitted text—note how everything, including the password, is visible
- Look for commands and responses in plaintext
This part of the lab is eye-opening. It reveals how insecure Telnet really is, making it clear why it’s discouraged in modern network environments.
4. Initiate SSH Session
Restart the Wireshark capture, this time using:
less
ssh [user]@[IP Address]
Again, log in and enter a few commands. Stop the capture after you’ve established and used the SSH session.
5. Analyze SSH Traffic in Wireshark
This time, the TCP payload will appear as encrypted gibberish. Unlike Telnet, you won't be able to read the commands or credentials, highlighting SSH’s encryption in action.
6. Compare and Conclude
Use the packet capture comparison to draw key conclusions:
- Telnet is unencrypted and exposes sensitive data
- SSH encrypts all traffic, protecting against eavesdropping
These comparisons are essential for anyone preparing for networking certifications using Exam Prep Dumps and Study Guide material. They not only prepare you for exam questions but also enhance your real-world security awareness.
Security Implications in Real-World Scenarios
Imagine a scenario where Telnet is used in a public or untrusted network. Any attacker with packet-sniffing tools like Wireshark can steal usernames, passwords, and other sensitive information.
Now picture the same scenario using SSH. Even with full packet captures, attackers won’t be able to decipher the encrypted content. This underlines the critical role SSH plays in secure network administration and why many exam questions highlight this difference.
Benefits of Doing the 21.2.12 Lab for Exam Preparation
Here’s how this lab aligns with IT certification goals:
- Reinforces the theory behind secure communication protocols
- Provides real-world examples of packet-level analysis
- Prepares candidates for troubleshooting-related exam questions
- Enhances your ability to differentiate between protocol functionalities
This makes the lab an essential part of Exam Prep Dumps and Study Guide material you might be using from trusted sources like DumpsQueen Official.
Common Issues Faced During the Lab and Their Fixes
- SSH/Telnet Service Not Running
- Use sudo systemctl start ssh or install telnet server (sudo apt install telnetd)
- Wireshark Not Capturing Traffic
- Ensure the correct interface is selected and Wireshark has necessary permissions
- No Packet Visibility During Sessions
- Check firewall settings and network connectivity
Tips for Successful Completion
- Always start Wireshark before initiating sessions to capture all handshake data
- Use Wireshark filters to narrow results (tcp.port == 23 or tcp.port == 22)
- Label each capture session (Telnet vs. SSH) to avoid confusion
- Use this lab alongside your Exam Prep Dumps and Study Guide material to cement the practical understanding
Final Thoughts
The 21.2.12 lab - examining telnet and ssh in wireshark is not just another step in your study process—it's a critical milestone. It brings theoretical knowledge into a practical arena, allowing you to observe real-time consequences of insecure vs. secure communications. By analyzing how protocols behave at the packet level, you not only become more prepared for exams but also more skilled for the workplace.
For the most reliable and structured Exam Prep Dumps and Study Guide material, always rely on DumpsQueen Official. Whether you're aiming to master protocols, pass with confidence, or grow your cybersecurity skills, this lab will serve as an indispensable tool in your learning journey.
Sample Questions Based on the Lab
- Which port does Telnet use by default?
A. 21
B. 22
C. 23
D. 25
Answer: C. 23 - What key security flaw is evident when using Telnet observed through Wireshark?
A. Encrypted traffic
B. Packet loss
C. Plaintext credentials
D. Slow response times
Answer: C. Plaintext credentials - In Wireshark, SSH traffic appears as:
A. Clear text
B. HTTP packets
C. Encrypted binary data
D. ICMP requests
Answer: C. Encrypted binary data - Why is SSH preferred over Telnet in secure environments?
A. Faster transmission speed
B. Better compatibility
C. Built-in encryption
D. No authentication required
Answer: C. Built-in encryption
