Technical Research on Obtaining YouTube IP Addresses via DNS Queries and ASN Analysis

Dec 01, 2025 · Programming · 8 views · 7.8

Keywords: YouTube | IP addresses | Firewall | DNS query | ASN analysis

Abstract: This paper explores technical methods for acquiring all IP addresses of YouTube in a Windows Firewall environment, focusing on the use of the DNS query tool dig and integrating ASN (Autonomous System Number) analysis to provide a systematic solution. By detailing the output of dig commands, it demonstrates how to extract IP addresses from DNS records and discusses using whois queries for ASN to obtain IP ranges. The article also compares the pros and cons of different technical approaches, offering practical references for developing anti-distraction tools.

Introduction

When developing custom anti-distraction tools, users often need to block specific websites such as YouTube. Since Windows Firewall only supports rules based on IP addresses, obtaining all IP addresses of the target site becomes crucial. Traditional methods like using hosts files or third-party applications have limitations, while brute-force enumeration of subdomains is inefficient. Based on technical Q&A data, this paper delves into effective methods for acquiring YouTube IP addresses through DNS queries and ASN analysis.

DNS Query Technology

DNS (Domain Name System) is the core technology for resolving domain names to IP addresses. Using the dig tool, one can query DNS records of a domain to obtain its associated IP addresses. dig is a common command in Linux and Unix systems, but it can be used on Windows by installing related tools (e.g., dig from the BIND package). Here is an example command and its output analysis:

dig youtube.com A

After executing this command, the output includes an ANSWER SECTION listing multiple IP addresses resolved for youtube.com. For instance, in the sample data, the dig query returned 16 A records, with IP addresses ranging from 74.125.235.32 to 74.125.235.47. These addresses typically belong to the same subnet and can be simplified into CIDR notation (e.g., 74.125.235.32/28) for efficient management in firewall rules. Note that DNS query results may vary due to caching and geographic location, so it is advisable to perform multiple queries or use different DNS servers for a more comprehensive list.

ASN Analysis Technology

Beyond DNS queries, another method involves obtaining IP address ranges based on ASN (Autonomous System Number). ASN is a unique identifier assigned to large networks (e.g., Google) on the internet. By querying YouTube's ASN (AS15169), one can use the whois command to retrieve all routing information. The specific steps are as follows:

  1. First, determine YouTube's ASN. For example, query youtube.com via an online tool (e.g., Networktools) to get ASN 15169.
  2. Execute the command in a terminal: whois -h whois.radb.net -- '-i origin AS15169' | grep ^route. This command retrieves all route records for AS15169 from RADB (Routing Assets Database), outputting multiple IP segments such as 64.18.0.0/20, 74.125.0.0/16, etc.

This method can obtain broader IP address ranges, covering all subnets potentially used by YouTube, but the results may include addresses not exclusively for YouTube, requiring further filtering.

Comparison and Integration of Technical Solutions

Comparing different methods, DNS queries (e.g., dig) provide currently active IP addresses, suitable for real-time blocking but may miss some addresses; whereas ASN analysis offers complete IP ranges but might be too broad. In practice, both can be integrated: start by using dig to get a basic IP list, then supplement with ASN queries for potentially missed addresses. Additionally, Google officially provides IP range lists (e.g., goog.json), which can serve as reliable references.

When setting rules in Windows Firewall, it is recommended to convert IP addresses to CIDR format to reduce the number of rules and improve efficiency. For example, consolidate the dig query results from 74.125.235.32 to 74.125.235.47 into 74.125.235.32/28. Regularly update the IP list to adapt to network changes.

Conclusion

Through DNS queries and ASN analysis, YouTube IP addresses can be effectively acquired, providing technical support for Windows Firewall rule configuration. The dig tool offers a direct resolution method, while ASN queries ensure comprehensiveness. Developers should choose or integrate these methods based on specific needs to achieve efficient anti-distraction functionality. In the future, with advancements in network technology, automated tools and APIs (e.g., Google's IP range services) may further simplify this process.

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