How to realize the principle of http proxy? From request forwarding to data encryption process analysis

What's the proxy server doing when you type a URL into your browser?

Imagine you order takeout and ask your neighbor to collect the package on your behalf, the HTTP proxy is similar to this transit role. When you set up a proxy in your browser, requests that would otherwise be sent directly to the target site are first routed around the proxy server. The most critical steps in this process areThree handshake transfers: The browser first establishes a TCP connection with the proxy, and then the proxy establishes a connection with the target website, which is equivalent to connecting the two "handshakes" in tandem.

 Simplified version of the proxy forwarding process (Python example)
def handle_client(client_socket).
    request = client_socket.recv(1024)
    target_host = parse_request(request) parse target address
    server_socket = socket.create_connection((target_host, 80))
    server_socket.send(request)
    server_socket.send(request)
        response = server_socket.recv(4096)
        if not response: break
        client_socket.send(response)

In practice, we also have to deal with HTTPS CONNECT method, certificate verification and other complexities. Good proxy services such as ipipgo will automatically deal with these technical details, users only need to configure the proxy address can be used directly.

How to encrypt data to keep it safe from the middleman.

Normal proxies do the data forwarding at the transport layer, while secure proxies will do it at the application layer. Take HTTPS for example:

1. Client sends CONNECT request to agent
2. Proxy establishes a tunnel connection to the target server
3. The client negotiates the SSL key directly with the server
4. Encrypted transmission of follow-up data throughout

Here's an easy point to confuse: although the proxy server can see the domain name (SNI information) you accessed, the exact content of the request is still encrypted. If you want to completely hide access traces, ipipgo'sTunnel AgentThe scheme will re-shell the entire communication packet through secondary encryption.

How dynamic IP pools enable automatic switching

Many crawler services need to change IP frequently to avoid being blocked, which involves the scheduling mechanism of the IP pool. Quality proxy service providers usually do this:

Take ipipgo's Dynamic Residential Proxy for example, their scheduling system can automatically decide whether to switch IPs based on the response status code, for example, switching to a new exit immediately after encountering a 403 error, which is smarter than switching at a fixed time.

Proxy Configuration Pitfalls for the White Guy

Many people clearly configure the proxy but it doesn't work, usually for these reasons:

- System Proxy and Browser Proxy Conflicts: Simultaneous settings will be based on browser settings
- Local programs do not go through the system agent: Some software needs to be configured separately
- IP whitelist not set: Proxy IPs need to be released on the server side
- Wrong authentication information: Note the format username:password@ip:port

If building your own proxies often goes wrong, it is recommended to use the ready-made proxy service provided by ipipgo directly, their client tool will automatically handle all kinds of configuration issues.

QA Session: High Frequency Questions on Agent Usage

Q: What should I do if my internet speed slows down after using a proxy?
A: Choose a provider that supports intelligent routing, such as ipipgo's cross-border line will automatically select the optimal line. Avoid using free agents, server quality is not guaranteed.

Q: What if I need to keep the same IP for a long time?
A: With static residential proxy, ipipgo's static IP can be maintained unchanged for 24 hours at the longest, which is suitable for the business that requires login state.

Q：How to solve the problem of "Proxy detected"?
A: Change to a more anonymous residential IP and set reasonable request intervals. ipipgo's dynamic IP comes with browser fingerprint masquerading.

Why choose ipipgo's proxy program

Conventional agents can only address basic needs, which are required for truly specialized business scenarios:

- E-commerce anti-association: each store is assigned an independent IP
- Ad placement: precise targeting to state/city level
- Data collection: automatic switching + failure retry mechanism
- Direct broadcast acceleration: Dedicated line to ensure transmission quality

For example, their TikTok solution ensures live streaming smoothness through exclusive bandwidth + native IP. Do cross-border e-commerce friends real test, with ipipgo after the account risk rate down 70%, commodity synchronization speed by 3 times.

When choosing a package, please note: if you need to change IP frequently, choose Dynamic Residential (starting from $0.5/GB), if you need stable and long time, choose Static Residential (starting from $15/month). Enterprise-level users are recommended to use customized plans, which can dynamically adjust the IP resource pool according to business needs.