# Technotes - [TCP Fast Open](https://kb.nssurge.com/surge-knowledge-base/technotes/tfo.md) - [HTTP Protocol Version](https://kb.nssurge.com/surge-knowledge-base/technotes/http-protocol-version.md): This document summarizes the differences between various HTTP protocol versions, as well as the impact of Surge activation on HTTP protocol versions. - [Local and Proxy DNS Resolution](https://kb.nssurge.com/surge-knowledge-base/technotes/dns.md) - [Testing Strategy for Automatic Policy Groups](https://kb.nssurge.com/surge-knowledge-base/technotes/testing-group.md): The testing strategy for Surge's automatic policy group is quite complex. This document provides a detailed description of the design behavior and rationale under various circumstances. - [Differences between REJECT Policies](https://kb.nssurge.com/surge-knowledge-base/technotes/reject.md) - [User Agent Rules](https://kb.nssurge.com/surge-knowledge-base/technotes/user-agent.md) - [NAT Types](https://kb.nssurge.com/surge-knowledge-base/technotes/nat-type.md) - [IPv6 RA Override](https://kb.nssurge.com/surge-knowledge-base/technotes/ipv6-ra.md) - [VM UDP Fast Path](https://kb.nssurge.com/surge-knowledge-base/technotes/udp-fast-path.md) --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://kb.nssurge.com/surge-knowledge-base/technotes.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.