The need for IP addressing

An Internet Protocol (IP) address is a Layer 3 logical address that is assigned to all devices on a network to allow communication between nodes on different IP networks. Imagine sending a letter to a friend or relative using traditional postal services. After writing the letter, you’ll need to include the sender’s address if the recipient wants to reply to your letter. Additionally, as the author of the letter, you’ll need to include the destination mailing address to ensure the courier service has all the details needed to deliver the letter to the right address and person. What if you forgot to include the source/sender address on the letter? The recipient will not be able to send any replies to you. What if you haven’t included the destination mailing address? The courier service will not be able to deliver the letter to the appropriate person.

Based on this analogy, the letter (message) is the electrical signal being generated...