% Chapter Template

\chapter{Results} % Main chapter title

\label{Results}

This chapter presents the results of the benchmark suite across all
ten VPN implementations and the internal baseline. Results are
organized by first establishing overhead under ideal conditions, then
examining how each VPN performs under increasing network impairment.
The chapter concludes with findings from the source code analysis.

\section{Baseline Performance}

Under the baseline impairment profile (no added latency, loss, or
reordering), the overhead introduced by each VPN relative to the
internal (no VPN) baseline and WireGuard can be measured in isolation.

\subsection{Throughput Overhead}

% TCP and UDP iperf3 results at baseline profile.
% Compare all VPNs against internal and WireGuard.
% Consider a bar chart or grouped table.

\subsection{Latency Overhead}

% Ping RTT results at baseline profile.
% Show min/avg/max/mdev per VPN.

\section{Impact of Network Impairment}

This section examines how each VPN responds to the Low, Medium, and
High impairment profiles defined in Chapter~\ref{Methodology}.

\subsection{Ping}

% RTT and packet loss across impairment profiles.

\subsection{TCP Throughput}

% TCP iperf3: throughput, retransmits, congestion window.

\subsection{UDP Throughput}

% UDP iperf3: throughput, jitter, packet loss.

\subsection{Parallel TCP}

% Parallel iperf3: throughput under contention (A->B, B->C, C->A).

\subsection{QUIC Performance}

% qperf: bandwidth, TTFB, connection establishment time.

\subsection{Video Streaming}

% RIST: bitrate, dropped frames, packets recovered, quality score.

\subsection{Application-Level Download}

% Nix cache: download duration for Firefox package.

\section{Tailscale Under Degraded Conditions}

% The central finding: Tailscale outperforming the raw Linux
% networking stack under impairment.

\subsection{Observed Anomaly}

% Present the data showing Tailscale exceeding internal baseline
% throughput under Medium/High impairment.

\subsection{Congestion Control Analysis}

% Reno vs CUBIC, RACK disabled to avoid spurious retransmits
% under reordering.

\subsection{Tuned Kernel Parameters}

% Re-run results with tuned buffer sizes and congestion control
% on the internal baseline, showing the gap closes.

\section{Source Code Analysis}

\subsection{Feature Matrix Overview}

% Summary of the 131-feature matrix across all ten VPNs.
% Highlight key architectural differences that explain
% performance results.

\subsection{Security Vulnerabilities}

% Vulnerabilities discovered during source code review.

\section{Summary of Findings}

% Brief summary table or ranking of VPNs by key metrics.
% Save deeper interpretation for a Discussion chapter.