What Is Backhaul (FAQ)
We all use the internet all the time, but how much do you know about the infrastructure? How does your device actually communicate with other devices around the world?
The full answer to that question is long and complicated, but you can understand a major portion of the internet and networking by learning about backhaul. It’s a key design component, and when you understand it, you can build better networks and find more efficient and effective ways to get devices to communicate.
What Is Backhaul?
To keep it simple, backhaul describes the hardware that connects core networks to sub-networks.
What does that mean?
The easiest example is to think of an internet service provider (ISP). They build and maintain the core network that connects basically all of the devices around the world. The major lanes of the internet are part of the core network. Meanwhile, if you want to hop online, you need to connect to that core network. Backhaul is the bridge between you and that primary infrastructure.
But, backhaul isn’t just for connecting to ISPs. If you were building your own data center, you would still have a local core network and subnets that need bridging, so you would use backhaul to make that happen.
A good analogy for all of this is to compare networks to roadways. When you’re in the city, you can take the local roads to get around town. That’s like being on the subnetworks. There are a lot of paths connecting a lot of different destinations, and the speeds and amount of traffic on any road usually aren’t that massive.
Then, you have the freeways. Speeds are higher. They service way more vehicles. The freeways are the core network. Backhaul would be the major roads that allow you to get to the freeway. It could include lesser highways and main thoroughfares.
In other words, backhaul can usually handle a lot of data and traffic at high speeds, and often at long distances.
What Are the Different Types of Backhaul?
Clearly, backhaul is an essential part of modern networking. How do you actually build it?
Technically, any device that can communicate could be part of your backhaul, but in practice, there are four primary types of backhaul, and the first two are far more common than the last two.
Wired
Wired connections are a huge portion of backhaul, and in many networks, the entirety of backhaul is wired. Since backhaul is usually trying to service large numbers of users at high speeds and potentially long distances, fiber optics are the primary choice for backhaul.
Wired connections are a huge portion of backhaul, and in many networks, the entirety of backhaul is wired. Since backhaul is usually trying to service large numbers of users at high speeds and potentially long distances, fiber optics are the primary choice for backhaul.
Still, not everything is run on optical lines, largely because of cost and practicality issues, and you can find plenty of examples of copper backhaul. Typically, for backhaul, the copper lines involved are in the faster spectrum, including T1 lines and other high-speed, long-range options.
For short backhaul runs, you might also see options like Cat8 and other fast copper connections.
Wireless
Wired connections are preferred for backhaul when available, but they aren’t always the practical choice. As distances grow and targeted access points get more remote, wireless becomes a great option.
For wireless backhaul, almost everything runs on microwave and millimeter communication bands, and to put this in perspective, a lot of wireless backhaul uses 4G, LTE, and 5G.
If you need backhaul coverage over a large area, then cellular backhaul is often the economical and efficient choice.
Satellite
Now, we’re getting into niche practices. There are circumstances where the subnets are so remote that even cellular isn’t practical. For those applications, satellite backhaul can get it done. Traditionally, satellite backhaul is not as fast and can’t handle as many users as wireless or wired backhaul, but it still remains the only viable choice in niche situations.
Wi-Fi
Last, we have Wi-Fi. Considering that backhaul often connects subnets across long distances, Wi-Fi isn’t the most common choice. But, it still shows up, and a specific example can help clarify how Wi-Fi works as backhaul.
In your home network, you probably connect to an ISP, and many home networks only have one modem. In fact, it’s common for that modem to also be a wireless router, and that all-in-one device can bridge your home network to the ISP. In that case, your Wi-Fi device is acting in the backhaul role.
In other networks, Wi-Fi can bridge backhaul to a node in a similar fashion. It doesn’t serve large distances, but Wi-Fi can be the easiest and most efficient way to bridge network components.
Ultimately, backhaul is about connecting network components in the best way possible, and the circumstances tend to dictate which kind of backhaul is right for a given network.
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