## 4 Performance Analysis and Evaluation
### Signaling Cost Analysis of IP-WSN  
We have evaluated our proposed model based on signaling cost, mobility cost and energy consumption. In the subsequent section we discuss the signaling cost analysis and energy consumption analysis with the help of different parameters mentioned in Table 1. Mobility cost is evaluated based on signaling cost. To evaluate total signaling costs, we compare the results of our analytical model with those of MIPv6 and PMIPv6. Figure 8 depicts the analytical model for the performance analysis of the proposed model. It consists of two different SPMIPv6 domains which are connected over the PMIPv6 based inter network. This Figure is the analytical representation of Figure 1. We may consider the individual SPMIPv6 domains as the different floors of the patient care unit. Distance between SMAG and IP sensor node is denoted by \(\text{D}_{\text{sn-smag}}\) and the distance between SMAG and SLMA is denoted by \(\text{D}_{\text{smag-slma}}\). The corresponding node (CN) considered as the specialist doctor is communicating with the visiting doctor. There are some visiting doctors who take the patient in continuous basis. In this analytical model, different distances are used for calculating signaling cost. The cost is incurred due to transmission of data and control signal. The cost will vary dew to different types of signal transmission. There may be five types of mobility scenario which has already been discussed in the earlier section. If patients move to a remote site then the signal will be transmitted through PMIPv6 domain. Other wise signal transmission will be restricted with in the SPMIPv6 domain. Figure 8: Analytical model for the performances analysis of SPMIPv6. From Equation (1) the total signaling cost (SC\({}_{\text{mipv6}}\)) of the proposed scheme based on MIPv6 is calculated by summing up the individual cost of intra-IP-WSN mobility (M\({}_{\text{intra-ip-wsn}}\). C\({}_{\text{sd}}\)) and inter-IP-WSN mobility (M\({}_{\text{inter-ip-wsn}}\). (C\({}_{\text{sd}}\) + C\({}_{\text{bu}}\))). Where, C\({}_{\text{sd and }}\)C\({}_{\text{bu}}\) are the sensor mobility cost and binding update cost respectively:  
\[\text{SC}_{\text{mipv6}}=\text{M}_{\text{intra-ip-wsn}}\cdot\text{C}_{\text{sd} }+\text{M}_{\text{inter-ip-wsn}}\cdot\text{(C}_{\text{sd}}+\text{C}_{\text{bu}}) \tag{1}\]  
where C\({}_{\text{sd}}\) and C\({}_{\text{bu}}\) are calculated in term of MIPv6 as follows:  
\[\text{C}_{\text{sd}}=\alpha\cdot\text{(RS}_{\text{mipv6}}+\text{ RA}_{\text{mipv6}})\text{ D}_{\text{sn-smag}}\] \[\text{C}_{\text{bu}}=\alpha\cdot\text{(BU}_{\text{mipv6}}+\text{ BA}_{\text{mipv6}})\text{ D}_{\text{sn-smag}}+\beta\cdot\text{(BU}_{\text{mipv6}}+\text{BA}_{\text{mipv6}})\text{ D}_{\text{smag-slma}}\]  
From Equation (2) the total signaling cost (SC\({}_{\text{pmipv6}}\)) of the proposed scheme based on MIPv6 is calculated by summing up the individual cost of intra-IP-WSN mobility (M\({}_{\text{intra-ip-wsn}}\). C\({}_{\text{sd}}\)) and inter-IP-WSN mobility (M\({}_{\text{inter-ip-wsn}}\). (C\({}_{\text{sd}}\) + C\({}_{\text{bu}}\))). Where, C\({}_{\text{sd and }}\)C\({}_{\text{bu}}\) are the sensor mobility cost and binding update cost respectively:  
\[\text{SC}_{\text{pmipv6}}=\text{M}_{\text{intra-ip-wsn}}\cdot\text{C}_{\text{ sd}}+\text{M}_{\text{inter-ip-wsn}}\cdot\text{(C}_{\text{sd}}+\text{C}_{\text{bu}}) \tag{3}\]  
where C\({}_{\text{sd}}\) and C\({}_{\text{bu}}\) are calculated in term of SPMIPv6 as follows:  
\[\text{C}_{\text{sd}}=\alpha\cdot\text{(RS}_{\text{pmipv6}}+\text{ RA}_{\text{pmipv6}})\text{ D}_{\text{sn-smag}}\] \[\text{C}_{\text{bu}}=\beta\cdot\text{(PBU}_{\text{pmipv6}}+\text{ PBA}_{\text{pmipv6}})\text{ D}_{\text{smag-slma}}\]