How to prevent blocking ip when using dynamic ip

Dynamic IP proxy is a kind of network service, which allows users to change different IP addresses every time they request a network. The core of this service is to dynamically assign IP addresses, so that users can hide their real IP, thus maintaining anonymity on the Internet. The working principle of dynamic IP proxy is that when a user sends a network request through the proxy server, the proxy server will assign a new IP address to the user randomly or according to some algorithm, so that each request will display a different IP, which increases the unpredictability of network activities.

When choosing a dynamic IP proxy service, users need to consider the stability, speed, price and security of the service. According to market research, paid agent service is usually better than free agent because of its stability and speed, and it has become the first choice for most professional web crawlers. For example, a survey of web crawler users shows that 90% of users who use paid proxy services are satisfied with the stability and speed of their services. In addition, paid proxy service providers usually provide API interfaces to facilitate users to integrate and automatically manage proxy IP.

When choosing a free agent, users need to be more cautious, because the availability and stability of free agents are often low. An analysis of free proxy service shows that the success rate of free proxy is usually less than 50%, which means that the network request has more than half the probability of failure. Therefore, even if the free agent can save costs, its lack of efficiency and reliability may affect the quality and efficiency of data collection.

The use of random request headers is an effective means to simulate real user behavior and reduce the probability of being recognized as a crawler. By randomly changing the request headers such as User-Agent and Accept at each request, the crawler can visit the website disguised as different browsers and devices. An experiment shows that the probability that a crawler using a random request header is identified as a crawler is reduced by more than 60%.

In addition, the random request header can also help the crawler to bypass some simple anti-crawling mechanisms, such as filtering based on the characteristics of the request header. For example, in a research on crawlers of e-commerce websites, it was found that the probability that crawlers without random request headers were banned within one hour was three times that of crawlers with random request headers.

Reasonable request interval setting is very important to prevent IP from being blocked. According to a study on reptiles of multiple websites, the probability that a crawler with a request interval of less than 1 second is banned is more than twice that of a crawler with a request interval of 1-2 seconds. Therefore, setting a reasonable request interval can not only reduce the risk of being banned, but also reduce the pressure on the target website server.

At the same time, the setting of request interval also needs to be adjusted according to the anti-crawling strategy of the target website. Some websites may respond quickly to high-frequency visits in a short period of time, so the crawler needs to flexibly adjust the request interval according to the actual situation to adapt to different anti-crawling environments.

For websites that need to log in, it is an effective strategy to use multiple accounts to visit in turn to slow down the speed of account blocking. By decentralizing requests, the risk that a single account is blocked can be reduced. A study on social media platforms found that the probability that a crawler using a single account for high-frequency access was banned was more than four times that of a crawler using multiple accounts in turn.

In addition, the use of multiple accounts can also increase the breadth and depth of data collection, because different accounts may access different data and information. However, this also requires crawler managers to invest more resources to maintain and update account information to ensure the effectiveness and activity of accounts.