A Simple Definition: A Basic Tunnel for TCP Traffic
SOCKS4 is an early proxy protocol from the 1990s that creates a simple network tunnel for TCP-based applications. Think of it as a basic bridge that forwards your internet traffic through a proxy server, but with significant limitations compared to modern alternatives.
Unlike HTTP proxies that only work with web browsers, SOCKS4 can handle any application that uses TCP connections - like old FTP clients, IRC chat programs, or legacy software that predates modern proxy protocols.
Your App
TCP connection
SOCKS4 Proxy
Basic forwarding
Target Server
Receives request
Important Context
SOCKS4 was developed in the early 1990s when internet requirements were much simpler. Most of its limitations stem from the design assumptions of that era.
The Critical Limitations of the SOCKS4 Protocol
While SOCKS4 served its purpose in the early internet era, it has several significant limitations that make it unsuitable for most modern applications. Here's what you need to know:
1. No UDP Support: Unsuitable for Modern Gaming & Streaming
SOCKS4 only supports TCP connections, which means it cannot handle UDP traffic. This is a major limitation because many modern applications rely heavily on UDP:
- Online Gaming: Most real-time multiplayer games use UDP for low-latency communication
- Video Streaming: Live streaming and video calls often use UDP for better performance
- DNS Lookups: Fast DNS resolution typically uses UDP packets
- Voice Chat: Applications like Discord use UDP for voice communication
Real Impact: If you're using SOCKS4 for gaming or streaming, you'll likely experience connection issues or poor performance because the proxy simply cannot handle the UDP traffic these applications need.
2. No Authentication: Lacks Basic Security
SOCKS4 has no built-in authentication mechanism, which creates serious security and access control issues:
Security Risks
Anyone who can reach the proxy server can use it, making it vulnerable to abuse and unauthorized access.
No User Management
Proxy administrators cannot control who uses their servers or track usage patterns.
This is why most SOCKS4 proxies you find online are either unreliable (overused by many people) or quickly become inaccessible as administrators shut them down to prevent abuse.
3. No IPv6 Support: Limited to Older Networks
SOCKS4 only supports IPv4 addresses, which is increasingly problematic as the internet transitions to IPv6:
- Cannot connect to IPv6-only websites or services
- Misses out on IPv6's performance and security benefits
- Incompatible with dual-stack networking configurations
- Creates connectivity gaps in modern network environments
Future-Proofing Note
As IPv6 adoption continues to grow, SOCKS4's IPv4-only limitation becomes more restrictive. Many modern services and CDNs are IPv6-first.
4. Client-Side DNS Lookups: Slower and Less Private
With SOCKS4, your device must resolve domain names (DNS lookups) before sending the request to the proxy. This creates several issues:
Privacy Leak
Your ISP can see which websites you're trying to visit, even though you're using a proxy.
Slower Connections
Extra DNS lookup step adds latency to every connection.
Geo-Location Issues
DNS responses reflect your real location, not the proxy's location.
In contrast, SOCKS5 can perform DNS lookups on the proxy server side, providing better privacy and often faster connections.
So, When Should You Actually Use SOCKS4?
Given all these limitations, you might wonder if there's ever a good reason to use SOCKS4. The honest answer is: very rarely, and only in specific legacy situations.
The Only Valid Use Cases:
Legacy Applications
When you must use very old software that only supports SOCKS4 and cannot be updated or replaced.
Embedded Systems
Some older industrial or embedded systems may have SOCKS4-only proxy clients built-in.
Testing & Research
For academic research or testing compatibility with legacy proxy protocols.
Network Administrator Insight
In 99% of scenarios, if you think you need SOCKS4, you actually need SOCKS5. Most applications that claim to "only support SOCKS4" actually support both protocols but default to the older version for compatibility reasons.
Before Choosing SOCKS4
Always check if your application can be configured to use SOCKS5 instead. Look in advanced settings, configuration files, or documentation - most software has been updated to support SOCKS5.
The Verdict: Always Choose SOCKS5 If Possible
SOCKS4 played an important role in the early development of the internet, but it has been completely superseded by its more powerful and secure successor, SOCKS5. For 99% of users and all modern applications, SOCKS5 is the correct choice.
Why SOCKS5 is Superior:
- UDP support for gaming & streaming
- Authentication for security
- IPv6 support for modern networks
- Server-side DNS for privacy
- Better performance & reliability
- Wide application support
Want to learn about the modern, feature-rich alternative?
Learn About SOCKS5 ProxiesFind a List for Your Specific Needs
If you've determined that you truly need SOCKS4 proxies for a specific legacy application, we maintain an updated list of available servers.
SOCKS4 Proxy List
Updated daily with working SOCKS4 servers for legacy applications.
View SOCKS4 ListSOCKS5 Proxy List (Recommended)
Modern SOCKS5 servers with authentication, UDP support, and better security.
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