CDMA is analogy where two people speaking the same language can understand each other, but not other people. Similarly in CDMA technique each user use same channel which is associated with a particular code can understand each other. Orthogonal spreading codes for CDMA used to avoid spoofing. . Spoofing is the act of falsely or maliciously introducing misleading or false traffic or messages to a network.orthogonal spreading code in CDMA has ability to avoid unauthorized network to listen in to a network and use information from the network without being a valid network member or participant. Orthogonal spreading codes can be used if all the users of the same channel are synchronized in time to the accuracy of a small fraction of one chip, because the cross-correlation between different shifts of Walsh functions is not zero (Forward channel). Thus SS signals can be made to have any degree of message privacy that is desired.