Remote Monitoring of COVID-19 Patients Using Multisensor Body Area Network Innovative System

Algorithm 1

Pseudocode for blowfish.

	Step 1: Input (64 bit) X as the text.
	Step 2: In the text, there are two 32 bit halves: and .
	Step 3: For I = 1 to 16:
	XOR PI.
	And is switched.
	Next, I.
	Again and XR are switched (The last switch was undone).
	=  XOR
	=  XOR
	Combinedand
	Step 4: Calculate Function f:
	is split into four eight-bit quarters: A, B, C, and D f () = ((, A + , B mod 232) XOR , C) + , D mod 232.
	Decryption:
	Instead, the decryption is similar, except the reverse order of , ………. is used.
	Generation key:
	Step 1: Initiated X boxes and P arrays.
	Step 2: The 32 critical bits of the first P array are XOR’d with the 32 key bits of the second P array, and so on.
	Step 3: The approach described above is used to encrypt all zero strings.
	Step 4: new input is provided by and
	Step 5: Using sub-keys, a completely new and have been encrypted.
	Step 6: and are the newly generated outputs.
	Step 7: Repeating this method 512 times yields a fresh P array and four S-boxes to be calculated.