### Contribution and Organization  
In this work, we analyze, compare, and evaluate the performance of universal decoding techniques for different key performance indicators (KPIs). The results are inferred from the study of research articles on the decoding techniques. The potential contribution  
\begin{table}
\begin{tabular}{c c c c} \hline
**Year** & **Paper [Ref]** & **Contribution** & **Limitation** \\ \hline \multirow{3}{*}{2023} & \multirow{3}{*}{[PERSON] et al. [16]} & Evaluation and & Variants of GRAND \\  & & comparison of many & and other decoding \\  & & potential URLLC & techniques not \\  & & decoding methods & considered \\ \hline \multirow{3}{*}{2024} & \multirow{3}{*}{[PERSON] et al. [17]} & Comprehensive review & \multirow{3}{*}{Decoding algorithms} \\  & & of primarily LDPC, & & scalable for 6G not \\  & & Turbo, and polar & & covered \\ \hline \multirow{3}{*}{2023} & \multirow{3}{*}{[PERSON] et al. [18]} & Highlights & No comparative \\  & & fundamental coding & analysis of \\ \cline{1-1}  & & schemes that have been & code-agnostic decoding \\ \cline{1-1}  & & commercialized & techniques \\ \hline \multirow{3}{*}{2023} & \multirow{3}{*}{[PERSON] and [PERSON] [19]} & Review on key & \multirow{3}{*}{Discussed KPIs,} \\  & & performance indicators & compared only for \\ \cline{1-1}  & & for 6G and trade-offs & LDPC and polar codes \\ \hline \multirow{3}{*}{2024} & \multirow{3}{*}{[PERSON] et al. [20]} & Review of channel & \multirow{3}{*}{Brief discussion on universal decoding} \\  & & coding techniques from & \\ \cline{1-1}  & & implementational & \\ \cline{1-1}  & & perspective in 6G & techniques \\ \hline \end{tabular}
\end{table}
Table 1: Contemporary work.  
of our work lies in the analysis, summary, and interpretation of the results of a performance analysis of key decoder metrics. The rest of the contributions of this work are as follows:  
* We discuss and present the algorithms of automorphism ensemble, guessing random additive noise, ordered statistics, bit flipping, and belief propagation decoding techniques, regarding their effective understanding and implementation.
* We summarize and analyze the key performance metrics of AED, GRAND, OSD, BFD, BPD, and their variants for their scalability toward the URLLC communication scenario of 6G.
* We provide a comparative analysis of the selected decoding techniques with the CA-SCL decoder of polar code as the benchmark, and we performed simulations in MATLAB for the error-correction performance of AED, GRAND, and OSD decoders on random linear code of dimension [128, 103].
* We discuss and list machine learning (ML) techniques that are implemented to enhance and optimize channel coding in 5G/6G networks.  
The structure of the paper includes six sections. Section 2 discusses the communication system model for universal decoding and includes a table of symbols and abbreviations. Section 3 describes the universal decoding techniques along with their algorithms. Section 4 carries out the comparative and performance analysis, including a summary table and a comparison table. Section 5 discusses the application of AI/ML models for universal decoding in context to 6G URLLC. Section 6 concludes the paper. Table 2 lists the symbols and abbreviations used in text and algorithms.