#### Summary:
In this lab we setup dhcp and used sniffers on our network.

I had no issues completing the lab
#### Summary of understanding:
- Document how to configure a DHCP pool on a Cisco router
	- **Set up DHCP Service on Router**

		1. Open the Router's CLI tab  
		2. To set up the DHCP service, you first must be in config mode.  
		3. Before we define the IP information to assign, we first are going to define the IPs we don't want to be used.
		    1. To exclude one IP address, we run the command `ip dhcp excluded-address [ip address]`.
		    2. To exclude a range of IP addresses, we use the command `ip dhcp excluded-address [ip address start] [ip address end]`.
		4. Now, we define the DHCP network, using the command `ip dhcp pool [pool name]`
		5. From _dhcp-config_ mode, we will run the cmmand `network [network address] [subnet mask]` for the network we want to define.  
		6. We will then use the command `default-router [ip address]` to assign the default gateway.
		    1. _Note: if you wanted to assign a DNS server, you would do so now with the command `dns-server [ip address]`  
- Document how to set up a sniffer (or two) on a network in Packet Tracer
	- You plug them in-between two devices, and set which port they should sniff on, after doing so you can set your filters to only see what you want.
- What are legitimate reasons a company may set up a sniffer on their organization? Provide at least 2.
	- To see where packets are being lost, for example if you are looking for where there is a packet drop error, you can setup sniffers to see if the packet got to that location
	- To see if there are breaches, for example if you start to see packets you do not normally see on a network you can be altered to a breach using sniffers.

**Packet Tracer - Class Lab**

**Objectives: Build a DHCP network and Observe HTTP Traffic**

**Goals:**

- Set up static network with connected server
- Configure DHCP on Cisco Router
- Utilize sniffers to observe DHCP and HTTP/HTTPS traffic

**Lab Steps**

1. Build the following network within Packet Tracer, but do not assign IP information to either PC:  
    ![image.png](https://champlain.instructure.com/courses/2682962/files/414593077/preview)  
      
    **SUBMIT: Screenshot of network with your name (2 Points)  
      
    ![[Pasted image 20261101210636.png]]
1. Ping default gateway from server

**SUBMIT: Screenshot of successful ping (1 Point)**
![[Pasted image 20261101212748.png]]
**Set up DHCP Service on Router**

1. Open the Router's CLI tab  
      
2. To set up the DHCP service, you first must be in config mode.  
      
3. Before we define the IP information to assign, we first are going to define the IPs we don't want to be used.
    1. To exclude one IP address, we run the command `ip dhcp excluded-address [ip address]`. In this case, we want to exclude **192.168.10.1** as our default gateway.
    2. To exclude a range of IP addresses, we use the command `ip dhcp excluded-address [ip address start] [ip address end]`. We want to exclude all IP addresses between **192.168.10.3** and **192.168.10.11**.  
          
4. Now, we define the DHCP network, using the command `ip dhcp pool [pool name]`, for which we will use **Workstation_Network**.  
      
5. From _dhcp-config_ mode, we will run the command `network [network address] [subnet mask]` for the network we want to define.  
      
6. We will then use the command `default-router [ip address]` to assign the default gateway.
    1. _Note: if you wanted to assign a DNS server, you would do so now with the command `dns-server [ip address]`  
          
        _
7. Type the `exit` command to conclude. To verify the network information, run the command `show ip dhcp pool` from admin mode.  
    **SUBMIT: Screenshot of DHCP Pool Command Output (3 Points)  
      ![[Pasted image 20261101210924.png]]
    **
8. Go to each PC and switch the IP Configuration type from Static to DHCP from the IP Configuration app under the Desktop tab.  
    **SUBMIT: Screenshot of each PC's IP information assigned dynamically (1 Point Each)**
![[Pasted image 20261101210943.png]]
![[Pasted image 20261101210952.png]]
**Traffic Sniffing in Packet Tracer**

1. From the End Devices > End Devices category, add 2 Sniffers to the workspace.
2. Delete the cable between the router and the switch on the 192.168.10.0 network, and reconnect the router to one sniffer and the switch to the other. Connect the sniffers together using a copper cross-over cable. It should look something like this:  
    ![image.png](https://champlain.instructure.com/courses/2682962/files/414596257/preview)  
      
3. You need to configure which port is going to be sniffed for each sniffer. If you connected the switch to Eth0 on the left sniffer, then make sure Port0 is selected on the GUI tab. The same is true for the right sniffer and the router.  
      
4. For each sniffer:
    1. Under the GUI tab, click Edit Filter, click Show All/None, and reselect ARP, DHCP, and ICMP on the IPv4 tab, and HTTP on the Misc tab.
    2. Click the Clear button to remove any extra packets that were sniffed.  
        **SUBMIT: Screenshot of GUI tab for each sniffer (1 Point Each)  
          ![[Pasted image 20261101211338.png]]
        **
5. Ping Server0 from PC0 using Command Prompt.  
      
6. From PC1, go to Server0 in the web browser by entering the IP address of the server and clicking "Go".  
      
7. For each sniffer, open the GUI tab and answer the following questions: **(2 Points Each)**
    1. How many packets of each protocol type were present?
	    1. 2 ARP
	    2. 4 ICMP
	    3. 2 HTTP
    2. Were the ICMP packets requests or replies?
	    1. On sniffer0 They were requests and on sniffer1 they were replys
    3. If there were ARP packets, what was the MAC address being requested and for what IP address?
	    1. In sniffer 0 there was two for the default gateway
		    1. TARGET MAC:0000.0000.0000
		    2. TARGET IP:192.168.10.1
		2. In sniffer 0 there were two for pc0
			1. TARGET MAC:0005.5EA1.A0CC
			2. TARGET IP:192.168.10.13
    4. For the HTTP packets, what port numbers were being used for the client and server, and what information was in the HTTP header?
	    1. Client HTTP Port was 1025 the destination port was 80
	    2. ```HTTP Data:Accept-Language: en-us  Accept: */* ```
    5. If there were DHCP packets, what stage(s) of the DORA process were sniffed?
	    1. There were no DHCP Packets
	6. ![[Pasted image 20261101211919.png]]

**Practice Saving Router config**

1. From Router: Config Tab: Save NVRAM  
      
2. From Router: Got to "Physical Tab" and use power button to turn off router.   
      
3. Power back on by clicking the button again  
      
4. Use Fast Forward button to get links back  
      
5. Check router to make sure DHCP pool is still there  
      
6. **SUBMIT: Screenshot of Router showing DHCP pool information (2 Points)**
![[Pasted image 20261101212026.png]]