# Faulty Links' Fast Recovery Method Based on Deep Reinforcement Learning
## 3 Faulty-Path Recovery Scheme Based on DDPG-LBBP
### DDPG-LBBP Agent Interacts with the Environment
\begin{table}
\begin{tabular}{c c} \hline \hline \multicolumn{2}{c}{**Glossary of Equation Terminology**} \\ \hline \(v\) & Switch \\ \(e_{i,j}\) & Link connecting switches \(v_{i}\) and \(v_{j}\) in the network topology \\ \(p_{s,d}\) & Path from source node \(s\) to destination node \(d\) \\ \(b_{i,m}(t)\) & Quantity of bytes transmitted by the \(m\) port of switch \(v_{i}\) at time \(t\) \\ \(R_{e_{i,j}}(t)\) & Utilization rate of link \(e_{i,j}\) at time \(t\) \\ \(loss\) & Packet loss rate \\ \(s\) & State \\ \(r\) & Action \\ \(grad\) & Gradient \\ \(\gamma\) & Discount factor \\ D & Experience replay pool \\ WAMS & Wide-area measurement system \\ SDN & Software-Defined Networking \\ DDPG-LBBP & Load Balancing Backup Path Based on Deep Deterministic Policy Gradient \\ PMU & Phase Measurement Unit \\ PDC & Phasor Data Concentrator \\ CNN & Convolutional Neural Network \\ GRU & Gated Recurrent Unit \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Glossary of equation terminology and abbreviations. ## References

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