Burmester Desmedt Key agreement. Is the division a floating point one or an integer one As I look upon Burmester Desmedt algorithm:



I notice that the intermediate key $K_i$ is getting calculated as:

$K_i=(k_{i+1}/k_{i-1})^{x_i} \mod p$

Thus I wonder wheher the division $k_{i+1}/k_{i-1}$ should result an integer of a floating point number.
Thus I wonder whether the division $k_{i+1}/k_{i-1}$ should result an integer of a floating point number.


An integer.

Specifically, this computation is done modulo $p$; that is, the result of this division is the value $d$ such that $d \cdot k_{i-1} \equiv k_{i+1} \pmod p$.

One way to find this $d$ is to compute the multiplicative inverse of $k_{i-1}$ modulo $p$ (for example, using the Extended Euclidean algorithm, and then multiply that inverse with $k_{i+1}$ (again, modulo $p$)