CCNA ensures that CCNP candidates possess a solid foundation of networking knowledge, which lays the foundation for the professional curriculum. Without that prerequisite foundation, the student may not be able to keep up with others in class and learn the advanced knowledge and skills presented in the CCNP courses.
Any One Who wants to do Cisco Certified Network Professional must have the base foundation certification called as Cisco Certified Network Associate because in ccna a person gets full basic knowelge of networking that is required to go to step second that is CCNP for more information cilck here