Magnetooptic methods have been used to study the critical dynamics in
concentrated Cd1-xMnxTe compounds (0.3 less than or equal to x less th
an or equal to 0.5). The occurrence of a spin glass phase transition a
t finite T-c has been characterized by the observation of the dynamic
scaling laws: An unique scaling function with identical critical expon
ents whatever the Mn composition support the existence of universality
among these spin glasses. The critical dynamic behavior is very simil
ar to that found in insulating Ising spin systems.