Hi, Vivek,
Configuration management knowledge base containing the versions and baselines of all official organizational standards, policies, procedures, and any project documents. Then it ALL materials with high confidentially to any company. It would be better to keep them is a safe place to avoid been hacked by a competitor.
Based on that, I think that a big company would store these documents at internal SharePoint, isolated by VPN, to prevent losing confidential information.
Understand SharePoint as a repository of files similar to Google Drive, but with only usage internal. VPN is a very sophisticated filter to protect the internal network from being accessed by hackers/competitors. This is my mental picture of a safe place to store essential documents for a big project.
I hope my explanations help you to understand it better. Let me know if you need additional information.
Regards,
Thiago