Reliable data transmission in wireless sensor network plays a critical part with the presence of increased data traffic and congestion. Successful data transmission can be ensured by providing cache resources to store the data before transmission. Reliable Transport protocol with a cache aware congestion control mechanism (RT-CaCC) is the existing approach used for secured communication. However, in this existing works, cache resource allocation is done evenly to all data flows on network which lead to data transmission failure due to insufficient resources. Cache resource allocation should be performed evenly in order to obtain consistent and successful data transmission. Priority based Cache Allocation and Congestion Control protocol (P-CACC) is used in this work for effective cache resource allocation. In the proposed research work, data transmission is performed reliably by giving more prioritization to the data flow with higher data rate. Here, initially uneven cache partitioning scheme is introduced for giving more prioritization to the flow with higher data rates. This is done by measuring the priority of the multiple data flows present in the network, and the weight assignment is done with the assistance of cuckoo search algorithm where the data flow with more priority will be assigned with more weight. The higher cache partition will be allocated to the data flow assigned with higher weight value. The simulation of the work is performed in NS2. It is confirmed that proposed research work tends to have improved outcomes than the existing techniques.