In this lesson, we will talk about the powerful trio. I will guide you completely through the definitions and functions of these communications and later, we will connect them with Ethernet MAC’s address. Let’s start, there is so much to learn about different type of communication and their functions.
1.Unicast. This term is used when we want to describe such a communication that has some piece of information that needs to be sent or has been already sent from one point to another. So, the point of the story is, for your best understanding, that we have here only one sender and only the one receiver. Unicast is still predominant when talking about LANs and the Internet. Also, all IP networks support unicast’s transfer mode. The standard unicast apps are FTP, HTTP, Telnet and more. They all have TCP’s transport protocol.
2.Broadcast. The broadcast is also a kind of communication where we have a piece of information that is as within unicast sent from one point, but the difference is that it is sent to all other points that exist. All connected receivers get that one information. It is also mostly supported on LANs. It is used for sending some particular and exact message to all LAN computers. You know a lot about IPv4, network layer protocol, and we can also connect it to broadcast communications. IPv4 has one host number, but it consists of IP and network’s ID too.
3.Multicast. What would be the multicast then? I am sure that you can guess the answer. This is a term used for such communication where we have some information sent from many points to some other numerous points. Also, I would like you to remember that multicast communications can also have one point from which the information is sent to a set of other points. So, what do we get here? We can have more senders or just one, but a piece of information is always set to many receivers. Sometimes, it may happen that there are no receivers, but there can be also numerous, depending on the information’s importance. Let’s see where can be multicast used! For your best understanding, let’s say that you are trying to figure out on which of these three types of communications a video server works. It is sending out networked TV channels, right? Such a high delivery quality of video definitely needs the simultaneous network receivers. So, the video server works on the multicast type of communication.
I have said that I will connect Ethernet MAC address to these communications. Why is that so? Because the Ethernet network is always using some two hardware addresses. It does it with a purpose to identify the destination and also the source of each frame that was sent from Ethernet. What about MAC’s address destination? It identifies the [intlink id=”141″ type=”post”]broadcast packet[/intlink] or sometimes even a multicast packet.
Hope that you have understood the meanings and the differences between unicast, multicast and broadcast. Soon, you will be ready to complete your Network Fundamentals Course!