🤖 Overview

The nsdl_search_bot is a web crawler operated by NTT Secure Data Labs (NSDL), a research division of NTT Corporation, one of the world’s largest telecommunications companies. Its primary purpose is to index publicly available web content to support the development of advanced security research, threat intelligence analysis, and large-scale data mining initiatives within NTT’s cybersecurity and AI projects. The bot is documented in NTT’s official User-Agent list and is part of a broader family of research-oriented crawlers that help train machine learning models for anomaly detection and network security.

🌐 Technical Behavior

According to NSDL’s published crawling policies (available at https://www.ntt-secure-datalabs.com/crawler-policy), nsdl_search_bot typically initiates requests from a dynamic range of IPv4 addresses belonging to NTT Communications’ AS2914, with occasional use of IPv6 prefixes from AS32098. The crawler employs a multi-threaded HTTP/1.1 client that follows standard robots.txt directives and includes a User-Agent header of Mozilla/5.0 (compatible; nsdl_search_bot/1.0; +https://www.ntt-secure-datalabs.com/bot.html). It fetches content at a moderate rate of approximately 5–10 requests per second per domain, with automatic backoff when encountering 429 or 503 responses. The crawler re-indexes sites weekly, but respects Cache-Control and Expires headers to avoid overloading non-static resources.

📋 robots.txt Compliance

NTT Secure Data Labs explicitly states in its official documentation that nsdl_search_bot fully honors Disallow directives in robots.txt, including wildcard patterns and per-path exclusions. The crawler also supports the Crawl-Delay directive to throttle its request rate on a per-site basis, as confirmed by NSDL’s public statement at https://www.ntt-secure-datalabs.com/robots-compliance. There is no evidence of intentional circumvention of robots.txt rules.

🔍 Detection Indicators

The definitive identifier is the User-Agent string nsdl_search_bot/1.0 accompanied by the comment field linking to the NSDL bot page. Additional behavioral fingerprints include the use of a X-NTT-Bot-ID header with a unique hexadecimal token per crawl session, and the absence of common browser-like headers such as Accept-Language or Referer. The bot’s IP addresses reverse-resolve to *.ntt-comm.net or *.ntt-secure-datalabs.com domains.

📊 Data Usage

Collected data is used exclusively for internal research by NTT Secure Data Labs—including training security-focused AI models for log analysis, phishing detection, and network anomaly identification. The crawler’s output also feeds NTT’s threat intelligence platform, which powers enterprise security products sold by NTT Ltd. No public search engine or consumer-facing service is built from this data.

⚙️ Rate Limiting Policy

Although nsdl_search_bot is legitimate and respects robots.txt, its sustained crawl rates can strain shared hosting environments. Rate limiting at 10 requests per second with a 30-second burst window is recommended to prevent resource exhaustion while allowing the bot to complete its research tasks effectively.

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the bots listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.