Update on Overleaf.

Appendices/SomeProof.tex

@@ -182,3 +182,29 @@ def run(args: argparse.Namespace) -> None:
 
 
 Each subcommand module (e.g., \texttt{fuzz/data\_fuzz.py}) provides its own parser configuration and encapsulated logic, adhering to a clearly defined interface.
+
+\section{APDU Status Word Codes}
+\label{sec:sw_codes}
+
+In the context of \gls{apdu} communication with \glspl{euicc}, each Response-APDU (R-APDU) from the card ends with a two-byte Status Word (SW), which indicates the outcome of the command execution. The SW is encoded as a 16-bit hexadecimal value and follows the ISO/IEC 7816-4 specification \cite{isoiec_isoiec_2006}.
+
+Some SW codes contain fixed values, whereas others use placeholders (represented as \texttt{??} or \texttt{XX}) to indicate that specific bits may vary, often encoding additional information such as a retry count or the number of bytes remaining. \cref{tab:sw_codes} provides an overview of some of the most frequently observed status words.
+
+\begin{table}[H]
+\centering
+\begin{tabular}{|c|p{10cm}|}
+\hline
+\textbf{SW Code} & \textbf{Meaning} \\
+\hline
+\texttt{9000} & Normal ending of the command. This indicates that the command was executed successfully and no further action is required. \\
+\texttt{61XX} & Command executed successfully; \texttt{XX} bytes of data are available for retrieval using a subsequent \texttt{GET RESPONSE} command. \\
+\texttt{91XX} & Command executed successfully; the card has sent a proactive command that the terminal must fetch. The \texttt{XX} indicates the length of the pending command. \\
+\texttt{6A82} & File not found. This error typically occurs when the requested EF (Elementary File) or DF (Dedicated File) does not exist in the current context. \\
+\texttt{6982} & Security status not satisfied. This usually implies that access conditions (e.g., PIN verification) were not met before executing the command. \\
+\texttt{6D00} & Instruction code not supported or invalid. The \gls{euicc} does not recognize the INS byte of the command. \\
+\texttt{6F00} & Technical problem with no precise diagnosis. Often a fallback or catch-all error code indicating an internal card error or undefined behavior. \\
+\hline
+\end{tabular}
+\caption{Common \gls{apdu} Status Words}
+\label{tab:sw_codes}
+\end{table}