Turbocharge Your Content Delivery With CDN Multiple Origins Load Balancer!

Turbocharge Your Content Delivery With CDN Multiple Origins Load Balancer!

With the ever-growing demands of the internet, websites and web applications face the challenge of delivering content swiftly and efficiently to users worldwide. Enter the concept of Content Delivery Networks (CDN) with Multiple Origins Load Balancing. 
‍

Just as a well-coordinated airport directs flights to multiple runways based on traffic and weather conditions, a CDN with Multiple Origins Load Balancing ensures that web traffic is distributed across various data centers, optimizing performance and reliability. 

‍

What is a CDN Multiple Origins Load Balancer?
‍

Think of a CDN Load Balancer (or LB, if you like to keep things short and sweet) as the internet’s traffic police. It takes on the crucial role of directing web traffic across various data centers, known as “origins.” Just like how a traffic cop ensures cars flow smoothly at an intersection, a Load Balancer makes sure data moves efficiently across the network. 
‍

But how does it decide where to send this traffic? That’s where rules come in. A Load Balancer operates based on a set of guidelines. These rules determine to which origin data center each request will be directed, based on customer-defined conditions, within the Content Delivery Network (CDN) infrastructure.
‍

For instance, you might set up rules to send video streaming requests to data center A and image loading requests to data center B. 

‍

What is “Origin”?

An origin typically refers to a data center where the content of a request resides and is processed. While it can occasionally be a specific server or even an application within a data center, it's predominantly the data center itself. When discussing web delivery and performance, it's crucial to differentiate between an origin (data center) and a Content Delivery Network (CDN).
‍

A CDN, or Content Delivery Network, is a network of servers strategically positioned across various locations to expedite content delivery to users based on their geographic location.

These patterns split into two main forms of traffic:

• Static Traffic: When a user request targets static content, the CDN first checks its cache. If the content is readily available, the CDN delivers it straight away, negating the need to retrieve it from the origin server. If the content isn't cached or has become stale, the CDN fetches it from the origin.
• Dynamic Traffic: This refers to the traffic that invariably reaches the origin, as it often involves real-time data or user-specific content. Given that all of this traffic makes its way to the origin tier, the role of load balancing becomes paramount. It ensures that the incoming requests are efficiently distributed among the available origin data center, preventing any single data center from becoming a bottleneck and thereby maintaining optimal performance.

Load Balancers play a crucial role in this process. They route traffic from the CDN to the origin tier, ensuring that user requests are efficiently directed to the best source. However, it's important to note that load balancing is primarily important for dynamic traffic, which is always routed to the origin.

If you're aiming for optimal web performance, a well-configured Load Balancer ensures that the workload is optimally distributed, and users receive data from the nearest and best-performing source.

‍

Why Use CDN Multiple Origins Load Balancer?
‍

Whether you’re running an e-commerce site or a streaming platform, your end goal is to provide an experience so smooth that your users forget they’re interacting with technology. 

This is where incorporating a CDN Multiple Origins Load Balancer can be a game-changer. 
‍

1. Intelligent Traffic Management for Complex Architectures

Consider a mammoth operation like Uber. It’s not a single app but a combination of functionalities ranging from ordering a ride, processing payments, customer support, and so on. 
‍

Each of these is managed by a separate microservice that resides on its own origin server(s). Now, if a user wants to book a ride, the Load Balancer routes that specific request to the “ordering” microservice.

This modular approach offers advantages like scalability, resilience, faster deployments, flexibility in and technology choices.
‍

At the same time, someone else paying for their ride will have their request sent to the “checkout” microservice. The Load Balancer all wonderfully plays it out!
‍

2. Balance Traffic Between Origins
‍

Consider having three data centers, each capable of performing the same tasks. Now, if we give a large chunk of the upcoming traffic to a single Data Center, the other two will sit idle, or conversely, if we try to just hit all three at the same time, we will have issues where the same request is being processed thrice. 

The solution? Let a Load Balancer decide what goes where to ensure that the incoming traffic is equally distributed among all three data centers. No single data center should be left to bear the brunt of all requests, preventing server overloads and meltdowns. 
‍

3. Balance Traffic Based on Geo-Location

The balancer knows where you are, making it even easier to ensure appropriate distribution. Here’s how it works:
‍

1. Regulatory Compliance: In Europe, user data must remain within the continent; any outbreak is terrible for you and your reputation. On the other hand, China wants access to its citizens’ online data; there’s no concept of privacy here. Similarly, different countries can have different laws, and some of them can clash with each other, making global rule-making useless. A Load Balancer in this context can split this traffic based on these geopolitical nuances, ensuring you comply with local laws. 
   ‍
2. Performance Matters: The physical distance between a user and a data center impacts the data transfer speed. If you have a data center in Europe and another data center in Korea, you’d naturally want your European traffic to access the European data center. Latency is a concept that increases with distance, so a signal that has to travel 1,000 KM will be much faster compared to a signal sprinting for that 100,000 KM.
   
   A Load Balancer can route a European User to a European data center and an Asian user to an Asian data center, achieving optimization, minimizing latency, and maximizing performance!

‍

{{promo}}

‍

4. Maintenance Without Mayhem

What happens when one of your servers/data centers needs a tune-up? Do you just give up the traffic trying to access it while you work on it? Or should you let the traffic temporarily access another server/data center until you’re finished with the tune-up?

The answer is pretty simple, but one that can be a significant pain if done manually every time. Assume a natural disaster occurs; being fast enough to make the change in this case would be quite hard.

Scheduled maintenance is a fact of life, and a Load Balancer helps you prepare for it. It can reroute all incoming traffic to other, fully operational origins, ensuring that your user experience remains uninterrupted. 
‍

Load Balancing Approaches

Now that we’ve established the “why,” let’s talk about the “how.” There are numerous ways to implement CDN Load Balancing, but the main approaches are limited to two: DNS-based Load Balancing and CDN Load Balancer. 
‍

Let’s take a look at both below:
‍

DNS as a Load Balancer
‍

The Domain Name System (DNS) is the internet’s phone book. When you type a website name, the DNS translates it into an IP address that computers understand. 

‍

In DNS-based Load Balancing, this system gets promoted from a simple translator to a traffic controller. It uses round-robin or traffic-splitting algorithms to distribute incoming requests across multiple data centers. 

‍

How It Works

‍

Here’s how it works: When an HTTP request reaches the CDN, the process of determining which origin server to send the request to involves a DNS resolution. As part of this, the CDN sends a DNS resolution request. The DNS then returns the IP address of the origin server based on various customer characteristics. This can include predefined static distributions (like an 80%/20% split) or be based on the Geo-location of the CDN server, among other factors.
‍

The selection of the server isn't purely random or solely based on a round-robin distribution. While these methods offer a straightforward way to distribute traffic, the system also incorporates Geo-location-based traffic balancing, ensuring that server choices are optimized for the location of the user.
‍

Limitations
‍

However, it’s worth noting that it doesn’t take into account the health or load of the target servers. Similarly, it lacks the ability to make decisions based on the HTTP request content of incoming requests, making it less flexible. 
‍

How DNS TTL Impacts Load Balancing?

1. A longer TTL implies that DNS information remains cached for prolonged durations. This approach minimizes the frequency of DNS lookups. However, a drawback is that it might utilize outdated server data, potentially redirecting traffic to servers that are either down or experiencing high traffic.
2. Conversely, a shorter TTL ensures the use of current server information. However, this necessitates devices to frequently re-query the DNS for IP addresses. This constant querying can introduce delays since every lookup consumes time, which might subsequently decelerate a user's access to a particular website or service.

CDN Load Balancer
‍

The CDN Load Balancer is the advanced, more sophisticated sibling of DNS Load Balancing. Often available with premium CDN services, this approach provides many features that go far beyond simply distributing traffic.
‍

How It Works
‍

Here, the Load Balancer holds onto the HTTP request and makes an educated decision on where to route it. Information embedded in the HTTP request, such as Geolocation and the type of content being requested, can influence this decision. 
‍

This enables smarter, more efficient load distribution.
‍

Advanced Features
‍

One exceptional feature is "Origin Failover." If one origin server is down or underperforming, the CDN Load Balancer detects it and reroutes traffic to a healthy origin. 
‍

Also, most advanced CDN Load Balancers offer analytics and real-time monitoring capabilities that allow you to tweak your rules and settings for optimal performance continually.
‍

Limitations
‍

On the flip side, the level of sophistication comes with a price tag. Not all CDN providers offer these advanced Load-balancing features. 
‍

Moreover, when you have a multi-CDN setup, each CDN Load Balancer only sees its own traffic, resulting in a less-than-optimal load distribution.

‍

{{promo}}

‍

Conclusion

‍

DNS-based load balancing is a swift and straightforward solution, yet it has its limitations. It can lack contextual decision-making based on HTTP request content and poses a vulnerability with its single point of failure. However, when integrated with a robust CDN Load Balancer, the combined system becomes a pivotal asset. Whether you're managing intricate microservices or streaming content to a global audience, a Load Balancer ensures efficiency, reliability, and compliance, elevating the user experience.

‍