Basic DHCP Overview

When it comes to going over the DHCP protocol, starting from the beginning and covering the basics is the most important to understanding this protocol. First off, what is DHCP, what does it effect and how does it work? These are all valid question when approaching this topic.

So how does this work in real time? Well, as you can see in the info-graphic above*:

1. When a network client boots up, it sends out a broadcast called DHCPDISCOVER. This is the client shouting, “I’m looking for a DHCP server that can assign an IP address to me.”

2. The DHCP Server distributes IP

3. When a DHCP server receives this broadcast, it responds with a DHCPOFFER message. This is the DHCP server saying, “I heard your request, and I can assign an IP address to you.”

4. The client receives this offer and responds with a DHCPREQUEST message. The client is now saying, “I accept your offer. Send me an IP address.”

5. The DHCP server seals the deal by sending a DHCPACK response. This response contains the IP address assigned to the client, and the length of the lease time.

6. DHCP can also be configured to send additional network information to clients. The most common information sent through DHCP to clients is:

7. The default gateway for the network the client is on.

8. The subnet mask being used.

9. A list of IP addresses for Domain Name Server (DNS) servers.

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Dig Deeper

• https://www.infoblox.com/glossary/dhcp-server/#:~:text=A%20DHCP%20Server%20is%20a,to%20broadcast%20queries%20by%20clients.

• https://youtu.be/Dp2mFo3YSDY

• https://youtu.be/S43CFcpOZSI

Resource

• https://www.certblaster.com/network-exam-objective-dhcp-basics/

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This week's Project milestone is to Install & Configure a Firewall & DHCP Server.

Week 7

Firewall Installation & Configuration

• Take steps to install and configure the firewall (iptables) on the web server.

• The workstation that hosts the web server may host other services; that is your decision.

• The firewall on the web server should only allow incoming traffic for the services hosted on the workstation and should deny all other traffic.

DHCP Server Installation & Configuration

Steps to configure the DHCP server. The DHCP server should

• Distribute IP addresses to anonymous clients in the range 10.13.175.0 through 10.13.175.255 with a 6-hour lease time;

• Ensure the primary DNS is 203.10.113.1 and the secondary DNS is 203.10.113.2;

• Ensure the subnet mask is 255.255.255.0; and

• Give each server workstation a host name and set up the DHCP server to give a fixed IP address to that workstation. For example, the web server workstation could be named "drv_web" and assigned the IP address 203.10.113.15 and the FTP server. If it is on a different workstation, it may be "drv_ftp" and assigned 203.10.113.10.