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1. Introduction
Many businesses use a proxy server to route and secure traffic between the networks. The proxy server acts as an intermediatory between the clients and servers. There are two types of proxy servers – Forward Proxy and Reverse Proxy.
In this tutorial, we’ll discuss what’s a forward proxy, what’s a reverser proxy, their use cases, and how they differ from each other.
2. Forward Proxy Server
It’s often referred to as just a proxy server. This type of server resides in front of the clients and acts as a mediator between the clients and the servers. The below diagram depicts the same:
The forward proxy ensures that the client request always goes through the proxy server first and then reaches the destination. One of the main purposes of the forward proxy is to process outgoing requests.
2.1. Uses of the Forward Proxy Server
- Client Anonymity: The forward proxy makes a request on behalf of the client. It masks the client’s IP address and provides client anonymity.
- Content Filtering: The forward proxy act as an entry point for all outgoing requests. This allows us to implement content filtering mechanisms like URL blocking.
- Logging and Monitoring: We can implement logging and monitoring with the forward proxy as all request goes through it.
- Performance Improvement: The forward proxy can boost the performance by leveraging caching mechanism.
2.2. Examples of the Forward Proxy Server
Below is the list of some of the popular forward proxy servers:
3. Reverse Proxy Server
The reverse proxy is part of the server-side infrastructure and resides in front of the web servers. It acts as an entry point for all incoming requests. The below diagram shows the same:
The reverse proxy ensures that the client doesn’t communicate directly with the web servers. One of the main purposes of the reverse proxy is to load balance the incoming requests.
3.1. Use Cases of the Reverse Proxy Server
- Server Anonymity: The reverse proxy provides server anonymity.
- DDoS Mitigation: The reverse proxy helps us in mitigating DDoS attacks by throttling incoming requests.
- Load Balancing: The reverse proxy helps us in implementing load balancing by redirecting requests to different instances of the servers.
- Stable Network Endpoint: It provides a stable client endpoint over changing server instances’ endpoints. The server endpoint can be affected due to scale up/down or node failure/node repair activity.
3.2. Examples of the Reverse Proxy Server
Below is the list of some of the popular reverse proxy servers:
4. Differences Between the Forward and Reverse Proxy Servers
Let’s discuss the differences between the forward and reverse proxy serves:
| Forward Proxy Server | Reverse Proxy Server |
|---|---|
| Handles outgoing requests | Handles incoming requests |
| Resides in front of the clients | Resides in front of the web servers |
| Provides client anonymity | Provides server anonymity |
| Can be part of the client-side infrastructure | It’s a part of the server-side infrastructure |
| Examples: PHP-Proxy, CGI-Proxy, Squid | Examples: NGINX, HAProxy, Istio, Linkerd |
5. Conclusion
In this tutorial, we briefly discussed the forward and reverse proxy servers. Then we discussed their use cases and examples.
Finally, we discussed how they differ in their functionality.