# Instantaneous Networking Service Availability for Disaster Recovery
## 5 Restoration of Networking Service Availability for Users in Multiple Areas
### Network Restoration Based on LI-Cloud  
By employing LI-Cloud, network restoration is enabled by two phases. One is the local restoration process. Another is the global restoration process. The local restoration process refers to the launching of LI-Cloud service for the local users. The procedure allows LI-Clouds to be deployed and configured in an isolated area after a disaster. The deployment of the LI-Cloud server can be carried out with cars, by a human, or just by switching on a predeployed server. The global restoration process refers to the procedure for connection to global services, such as social media tools. The analytical scenario adopted in this section assumes that there is no interconnection among LI-Clouds in different areas. The differences of the proposed LI-Cloud method from the conventional networking service provision are as follows. In case X is in A and Y is in A, we can write the probability of communication connection between X and Y as  
\[PL_{A\sim A}(t)=P_{A}(t). \tag{16}\]  
In case X is in B and Y is in B, we can write the probability of communication connection between X and Y as  
\[PL_{B\sim B}(t)=P_{B}(t). \tag{17}\]  
In case [PERSON] is in C and Y is in C, the probability of communication connection between X and Y is  
\[PL_{C\sim C}(t)=P_{C}(t). \tag{18}\]  
Let the probability of CaseBG be \(PL_{CaseBG}\). We have  
\[PL_{CaseBG}=F_{BG}\cdot P_{B\sim G}(t). \tag{19}\]  
Let the probability of CaseCC be \(PL_{CaseCC}\). We have  
\[PL_{CaseCC}=F_{CC}\cdot P_{C\sim C}(t). \tag{20}\]  
\begin{table}
\begin{tabular}{l l} \hline \(P_{A}(t)\) & Accumulated probability of launching of distributed cloud A at time \(t\) \\ \hline \(P_{B}(t)\) & Accumulated probability of launching of distributed cloud B at time \(t\) \\ \hline \(P_{C}(t)\) & Accumulated probability of launching of distributed cloud C at time \(t\) \\ \hline \(P_{AC}(t)\) & Accumulated probability of launching of global connectivity in area A at time \(t\) \\ \hline \(P_{BC}(t)\) & Accumulated probability of launching of global connectivity in area B at time \(t\) \\ \hline \(P_{CG}(t)\) & Accumulated probability of launching of global connectivity in area C at time \(t\) \\ \hline \(PC_{A\sim A}(t)\) & Probability of successful communication between two users in A \\ \hline \(PC_{B\sim B}(t)\) & Probability of successful communication between two users in B \\ \hline \(PC_{C\sim C}(t)\) & Probability of successful communication between two users in C \\ \hline \(PC_{A\sim B}(t)\) & Probability of successful communication between a user in A and a user in B \\ \hline \(PC_{A\sim C}(t)\) & Probability of successful communication between between a user in A and a user in C \\ \hline \(PC_{B\sim C}(t)\) & Probability of successful communication between between a user in B and a user in C \\ \hline \(CaseAA\) & The case that one user in A attempts to communicate with one user in A, and the communication succeeds. \\ \hline \(CaseBB\) & The case that one user in B attempts to communicate with one user in B, and the communication succeeds. \\ \hline \(CaseCC\) & The case that one user in C attempts to communicate with one user in C, and the communication succeeds. \\ \hline \(CaseAB\) & The case that one user in A and one user in B attempt to communicate with each other, and the communication succeeds. \\ \hline \(CaseAC\) & The case that one user in A and one user in C attempt to communicate with each other, and the communication succeeds. \\ \hline \(CaseBC\) & The case that one user in B and one user in C attempt to communicate with each other, and the communication succeeds. \\ \hline \(CaseAG\) & The case that one user in A attempts to communicate with one user in G, and the communication succeeds. \\ \hline \(CaseBG\) & The case that one user in B attempts to communicate with one user in G, and the communication succeeds. \\ \hline \(CaseCG\) & The case that one user in C attempts to communicate with one user in G, and the communication succeeds.