Task-2 Study the network diagram below: S1 R z H D B . The first subnet have nodes (H, B, R and the server S1) and they are connected to subnet2 via (R-Z and B-M) internet connection. The second subnet consists of nodes (M, D, and Z). The Client H in Subnet-1, wants to communicate with Client D in Subnet-2 and for this purpose the following criteria should be considered 1. Subnet-1 and Subnet-2 are connected through unsecured internet connection for this reason no keys should be exchanged and any message exchanged between should be Digitally certified and encrypted 2. Subnet-1 have the server S1 in which it can provide PKI services 3. Subnet-2 does not have any arbitrary or uninterested third party certifier so nodes have to find a way to communicate securely 4. You have to use two different protocol for each subnet to exchange session key between Hand D. Write the necessary steps including the format/calculation needed for the communication to be established. 2