Load Balancing is defined as the canonical and efficient distribution of network or application traffic among multiple servers in a server farm. Each Load Balancer is located between client devices and backend servers and distributes incoming requests to any server that can fulfill them.
A Load Balancer can have:
It can be a virtualized machine (Virtual Appliance) or a physical device,
Included in application delivery controllers (ADCs) designed to more broadly improve the performance and security of three-tier web and microservice-based applications, regardless of where they are hosted.
Many possible load balancing algorithms can be leveraged, including round robin, server response time, and least connection method, to distribute traffic in line with current requirements.
Regardless of whether it's hardware, software, or whatever algorithm is used, a load balancer distributes traffic to different web servers in the resource pool to ensure that no single server becomes overworked and later inaccessible. Load balancers effectively reduce server response time and maximize throughput. In fact, this is exactly the task of a load balancer. Of course there are different variations of this.
We can think of Load Balancers like a traffic cop. It undertakes the task of directing incoming requests to the right locations instantly and systematically. In this way, it prevents blockages and unforeseen problems that may cause high costs. It does not just assume the role of administrator and router in complex IT environments; it also provides the necessary performance and safety.
Load Balancing is the most suitable methodology for managing numerous incoming requests in multi-application and multi-device workflows. With platforms that provide seamless access to a wide variety of applications, files, and desktops in today's digital work environments, load balancing supports a more stable and reliable end-user experience for employees.
Hardware vs. Software Based Load Balancers
As we mentioned that Load Balancers can be both hardware and software. Let us touch on the differences between them.
Here's How Hardware Based Load Balancers Work;
These devices are high-performance devices that can securely handle multiple gigabits of traffic from various types of applications. It also has built-in virtualization capabilities, combining multiple virtual load balancer stages on the same hardware.
Among other advantages, it provides complete isolation in multi-user structures.
Here's How Software-Based Load Balancers Work;
It has the same functionality and can be preferred over a load balancing hardware.
They run as Linux processes on familiar hypervisors, containers or physical servers with minimal overhead and are highly configurable virtual appliances depending on the use cases and technical requirements needed.
They reduce hardware expenses and save physical space.
Software-based load balancers are at least as good as hardware ones, but due to some of the situations I have experienced in this regard, I can say that virtual load balancers are a good solution to a certain extent in complex, heavy traffic, multi-user and multi-application structures. At this stage, the topology created by friends who are experienced in networking comes into play. The software supports up to 300 users, there are 1000 users in the structure, a virtual load balancer is desired, then it can be decided by watching the flow on the scheme. Saying no and cutting it out would be misleading.
L4, L7 Load Balancers
Digital work environments are largely application-based. Especially in these days when the demand for service SaaS applications is increasing, delivering these applications to end users reliably and quickly will not provide sufficient efficiency in a structure without load balancing. This will cause performance degradation and will put some of this unbalanced load on users.
To provide greater consistency and keep pace with ever-evolving user demand, server resources must be ready and load balancing at layers 4 and/or 7 of the Open Systems Interconnection (OSI) model:
Layer 4 (L4) load balancers operate at the transport level. This means that packets can make routing decisions based on the TCP or UDP ports they use, along with their source and destination IP addresses. L4 load balancers perform Network Address Translation, but do not check the actual content of each packet.
Layer 7 (L7) load balancers operate at the application level, which is the highest in the OSI model. When deciding how to distribute requests across the server farm, they can evaluate a wider range of data than their L4 counterparts, including HTTP headers and SSL session IDs.
Load balancing is numerically more intensive in L7 than in L4, but can also be efficient in L7 due to the added context of understanding and processing client requests to servers.
That is all what I wanted to share with you about Load Balancing.
Thank you
