## 2 Related Works
However, MRC's significant deployment overhead, potentially due to the necessity of maintaining and updating multiple configuration graphs and associated routing information, is a major drawback. The FCP (free routing using failure-carrying packets) [26] algorithm's defining feature is its ability to denote failure information in the packet header. Utilizing this failure information, the FCP algorithm can dynamically update the network topology to accurately reflect the current state of the network. However, an inherent shortcoming of the FCP method is its requirement for modifications to the existing routing protocol. This could escalate the complexity of the actual deployment process due to the need for alterations and resets of network equipment and protocol stacks. Table 1 summarizes the advantages and disadvantages of the relevant algorithms. The following four articles each present innovative breakthroughs and notable limitations within the realm of IP Fast Reroute (FRR) [27]: Ref. [28] integrates centralized control with local rerouting to facilitate IP network load balancing and achieve 100% single-failure survivability. However, its dependence on false nodes and scalability issues due to ILP size pose considerable constraints. Ref. [15] introduces a novel DLCP graph sequence decomposition method that leverages local connectivity to construct efficient routing trees, thereby overcoming the limitation of global connectivity. However, the use of heuristic rules may result in the sacrifice of some path quality. Ref. [29] focuses on enhancing the performance and resilience of existing routing trees through the post-processing of arc exchange, providing support for SRLG isolation. Despite these improvements, it only serves as an auxiliary measure and fails to address the initial decomposition defects. Finally, Ref. [30] presents the development of the SYREP, which employs BDD to enable rapid routing table repair and achieve k-resilience synthesis. This results in a speed increase of \begin{table}
\begin{tabular}{l l l} \hline \hline
**Algorithm** & **Advantages** & **Disadvantages** \\ \hline \multirow{2}{*}{ECMP} & No auxiliary mechanism; simple; & Restricted to equal-cost paths; \\  & load balancing & poor flexibility \\  & No extra mechanism; low & Topology-limited; modest \\  & overhead & protection coverage \\  & Simple structure; small & Mediocre protection; \\  & path-stretch & low adaptability \\  & Downstream criterion; & Variable protection; \\  & scenario-specific & topology-dependent \\  & DC & DAG-based loop-free backups & No performance data; \\  & & unclear applicability \\  & & & \\  & Uses bi-directional Joker links & 95\% protection rate; \\  & LFID & Ingress-port redundancy & Unstable protection (88.9–98.2\%) \\  & ESCAP & Guards any single-node failure & High path-stretch; hurts \\  & & latency-sensitive traffic \\  & Rapid failure reaction via & Protocol changes; \\  & Not-Via & complex deployment \\  & Dynamic link cost adjustment; & High maintenance overhead \\  & multi-config & Protocol-stack changes; \\  & & compatibility issues \\  & & Topology-sensitive; high \\  & & path-stretch \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Summary of advantages and disadvantages of some routing protection algorithms. three orders of magnitude. However, its applicability is limited by complex network scale and computational bottlenecks in scenarios involving more than three failures.