Network Routing: The Basics
Whether you want to watch a live stream or make your network run more efficiently, multicast routing is key. There are three basic types of traffic for networking: unicast, broadcast and multicast. Unicast allows you to send from one source to one destination. A great example of unicast is website traffic flowing from one server to a client device. Broadcast, on the other hand, lets you send from one source to all possible destinations on a network. Television networks use broadcasting.
However, if you want to send a message from one source to a specific group, that’s where multicast comes in. In a way, multicast lies between the extremes of unicast and broadcast. Multicast is a technology that allows you to replicate one stream on a network to many hosts. It uses a designated range of IP addresses for communication. With multicast, a source sends one copy of data to one multicast address, which then distributes data to multiple recipients. It provides a more efficient method for delivering traffic that can be thought of as one-to-many.
The Benefits of Multicast
Broadcast is an extremely inefficient for the majority of applications. It’s not realistic over the internet because users would be constantly receiving a huge amount of unnecessary information. The bigger question is why you would want to use multicast instead of unicast.
Multicast is more efficient
For one, multicast routing is more efficient than unicast routing. With broadcast routing, all devices will receive the stream whether or not they have joined a specific multicast group. Only devices that want to receive the multicast stream will join a multicast group.
Internal video training
In an organization where video content is shared internally for training, multicast may be a better choice than using unicast streams. Multicast uses group communication where a host will announce it wants to join a specific multicast group for a specific stream.
Secure corporate communications
No IT department will ever argue that there is too much security. Even if you are diligent about network security, it helps to add an extra level to your internal videos. Multicast streaming is a far more secure option than using a third-party unicast OTT streaming application to deliver content over the internet. With multicast, you’re operating within a secure, private IP network.
Do we need multicast?
The question remains: is multicast still a technology we need in a gigabit network era? Even as networks get faster and more bandwidth becomes available, we will always have a finite amount of network sources to use for transferring data. If we can optimize the transmission of data, this will increase the range of how far network resources can be used.
One great example is the internal video training discussed earlier. In today’s gigabit networks, multicast enables you to have 1 stream to 100 hosts instead of 100 streams going to 100 hosts. This is far more efficient and saves on network resources.
Multicast dramatically reduces your network traffic by offering a single source of communication to simultaneous multiple recipients. It is an excellent way to push data to multiple hosts, and will always have a place in networking.