Link Load Balancers Fundamentals: All You Need to Know About

Enterprise networks are constantly under pressure to handle requests from a variety of clients with different needs. As a result, it’s critical to ensure the traffic meets its request, applications are available, and no machine, server, or router crashes due to the load.

When all of the above is achieved, it ensures business continuity, high availability, and heightened performance; resulting in impressive client service.

That’s where load balancers come into play; ensuring high availability without compromising the capacity of your servers or routers.

In this blog, we’re discussing what is link load balancing, and clarify the difference between link balancing and load balancing.

What Is Link Load Balancing?

When enterprises are experiencing high traffic volume, they opt for multiple ISPs (internet service providers) and WAN links to create a multi-homing architecture. This architecture manages the load between multiple WAN links ensuring redundancy and high performance. Link balancing hardware usually sits between the LAN-WAN boundary, monitoring and balancing the traffic.

It’s the backbone of any data center today, because in today’s high-speed world, it’s integral to have access to an internet connection 24×7. Problems like outages and downtime can cause astronomical losses to businesses only within a couple of hours. Thus, businesses are embracing solutions like link balancing to eliminate such issues. It’s beneficial for outbound traffic as well as inbound traffic from clients or partners.

What is the Difference Between Link Balancing and Load Balancing?

While often used interchangeably, link and load balancers are different concepts.

However, both of them strive to accomplish a similar purpose: to ensure that incoming traffic is smartly split up and distributed among available servers or routers to fulfill the traffic’s request. At the same time, it ensures no router or server is overwhelmed or exhausted.

While link load balancers work for internet connections, load balancers work for application servers.

How Do Link Load Balancers Work?

Link balancing works by using various traffic management algorithms to send traffic to the available data links. Here are some of the commonly used algorithms:

1. Round robin

Configured most commonly, round-robin is a fairly common practice in load balancing. It works by sequentially rotating the traffic among available links. Thus, it sends traffic to each router one after the other in cycles.

2. Weighted round-robin

Similar to round-robin, the weighted round-robin works by manually configuring and assigning weight to each router. So, for example, if router #1 is assigned more weight than links #2 and #3, it will take on heavier loads and more traffic than the other two links. This way, you can manually configure and decide the link’s capability.

3. Shortest response time

In this algorithm, traffic or request is first assigned to the router with the least number of active connections and shortest average response.


Advantages of Using a Link Load Balancer

1. Redundancy

With link balancing, you don’t have to worry when one of the links is down for maintenance or other reasons. We know that even a few hours of downtime can significantly impact an organization’s productivity. Therefore, during such instances, the traffic is switched to other links, ensuring high availability. This process is automated and immediate.

2. Allows Easy Maintenance

Admins can manually switch off the routers and display “down” as the status. In this case, the incoming traffic will not be diverted to the down link instead be switched over to other available links. This allows conducting routine maintenance without interrupting the flow of traffic.

3. Enhanced Performance

By balancing weight or requests received by various WAN links, your organization can achieve enhanced performance.

4. Health Checks

Since the balancer transfers load to the available links, it also checks their health to ensure they can accommodate traffic. Thus, it monitors the health of individual links in real-time. Besides, it performs the bandwidth and performance checks using TCP, HTTP, Ping, and DNS.

Final Words

Link load balancers are an excellent solution to your enterprises’ everyday problems. By distributing the load evenly, you can achieve heightened productivity and availability. Link load balancers also reduce cost since they can work with any kind of broadband connection. For further information on link load balancers and to know about the best solution for your enterprise, talk to our sales now!

Learn more about what load balancers are, along with their type and benefits, here.