Have you ever wondered how some of the largest websites manage millions of users at the same time without collapsing? Or how your data gets transferred securely to the right server every time you make a request?
Let’s break things down by exploring three critical components of modern web infrastructure: proxies, reverse proxies, and load balancers.

Even if you’re not an engineer, understanding these will give you a peek behind the scenes of how the internet actually works.

Forward Proxy: Your Internet Personal Assistant

Imagine you’re planning dinner at a popular restaurant, but you don’t want to interact directly with the staff — maybe you’re shy, tired, or just can’t be bothered. So you have a personal assistant who makes the reservation for you. The restaurant talks only to your assistant, not to you.

In this analogy:

• You = your laptop

• Your assistant = a proxy server

• Restaurant = websites on the internet

A proxy sits between your private network and the public internet. It acts as a middleman, filtering traffic and blocking harmful websites, scripts, or code before they ever reach you.

Why companies need forward proxies even more

In a corporate setting, the stakes are higher. Employees browse all kinds of sites — some safe, some questionable. If a marketing employee accidentally downloads a file containing a hidden virus, that malware can slip through their computer into the company network and cause major damage.

A forward proxy protects the entire internal network by:

• Filtering requests

• Blocking blacklisted websites

• Scanning responses for viruses or malicious content

• Logging user activity

• Caching responses to save bandwidth

Example: If one engineer watches a tutorial and the proxy caches it, the next 10 engineers will watch the cached copy instead of downloading it again. This reduces traffic significantly.

This type of proxy is also known as a forward proxy.

Reverse Proxy: The Receptionist for Incoming Traffic

Back to the restaurant. You arrive for dinner, but instead of wandering around, you check in at the reception desk. The receptionist seats you at the right table based on availability and flow.

That receptionist = reverse proxy.

A reverse proxy sits in front of servers and handles incoming requests. It decides which server should handle which request. This distribution of clients across servers is called load balancing, but load balancing is only one feature of a reverse proxy.

What reverse proxies do

Reverse proxies:

• Distribute incoming traffic across multiple servers

• Protect backend servers by hiding them from the internet

• Enforce SSL/TLS encryption

• Scan requests for security threats

• Cache frequently requested content

• Log traffic for monitoring and debugging

One of the most widely used reverse proxies is Nginx.

Load Balancing: Just One Superpower of a Reverse Proxy

It’s easy to confuse reverse proxies with load balancers, but here’s the key insight:
Load balancing is just one of the many tasks a reverse proxy can perform.

Think of it like the receptionist deciding:

• Which table has space

• Which area is less busy

• Which guests get their favorite table

• Which guests need a special menu

Load balancing can be simple or complex depending on the tools.

Cloud Load Balancers vs. Reverse Proxies: Do You Need Both?

A common question is:
“If cloud platforms like AWS or Azure already have load balancers, why bother with a reverse proxy like Nginx?”

The short answer: you want both.

Why both layers matter

A typical setup uses:

• Cloud Load Balancer → entry point into your private network

• Reverse Proxy → intelligent routing within your server network

This layered design:

• Improves scalability

• Improves security

• Allows deeper, more customizable routing

Cloud load balancers vs. reverse proxies

Cloud load balancers use simple algorithms like:

• Round robin

• Least connections

Reverse proxies allow fine-grained routing, based on:

• Cookies

• Headers

• Sessions

• URL paths

• User affinity (same user → same server)

They can also do SSL/TLS termination and inspect encrypted traffic before routing, which is crucial in microservice architectures.

Restaurant example again

The cloud load balancer is like a doorman guiding guests into the restaurant.
The reverse proxy is the receptionist deciding:

• “This returning guest likes table 7.”

• “This vegetarian guest should get the plant-based menu.”

• “This group needs a bigger table in the back.”

Kubernetes Example: Ingress + Cloud Load Balancer

In Kubernetes:

• The cloud load balancer handles external traffic

• The Ingress controller (a reverse proxy) handles internal routing inside the cluster

Same layered structure, same logic — just in a containerized world.

What About Servers That Start Automatically in Node.js or Java?

When you run a Node.js or Java application, you often get a lightweight server that starts automatically. These are not full-featured reverse proxies — they’re basic HTTP servers.

Node.js example

Node.js doesn’t include a reverse proxy natively, but you can build one using:

• Its built-in HTTP module

• Express.js framework

Nginx vs. Express.js

• Nginx: a high-performance server + reverse proxy

• Express.js: a minimal web framework for building dynamic APIs and apps

In production, these are often combined:

• Nginx handles static files, load balancing, and SSL

• Express.js handles application logic and dynamic content

Nginx is much more efficient at handling large numbers of concurrent connections.

Bringing It All Together

Once you understand the roles of:

• Forward proxies

• Reverse proxies

• Load balancers

…the entire architecture becomes much clearer.

Forward proxies protect clients.
Reverse proxies protect servers.
Load balancers distribute traffic.
And in modern systems, you typically use all of them — often in multiple layers.