Cisco certification is a certification system, which contains a variety of certifications, different certifications and their re-certification methods are not the same, the more common are the following three: CCNA re-certification: you can re-take the ccna exam, you can also directly test one of the ccnp exams, exams passed in order to continue to use the ccna. ccnp re-certification: there are three ways to refresh the validity of the exam, take a ccnp core exam, or examined two ccnp elective exam, or examined CCIE experimental exam. ccie re-certification: ccie is valid for three years, the validity period is over, you must re-take the written and experimental exams, exams over to refresh the validity of the ccie certificate. cisco certified network engineer what is it to obtain the Cisco Network Engineer certification is known as a cisco certified Network Engineer. The profession of Cisco Network Engineer stands in the ranks of industry leaders, highly recognized in the IT industry, and is regarded as the first class of high-paying professions in the 21st century. A person with a Cisco certification is more likely to get a well-paid job, and at the same time get Cisco certification can also prove their excellent technical standards. cisco certification exam is difficult cisco certification is a certification system, which contains a variety of certifications, different certifications are not the same difficulty. Cisco certification exam is the most difficult ccie certification exam, it is in addition to the preparation work requires a lot of time in addition to the content of the exam is also more, but also need a lot of experimental experience in order to pass, and ccie compared to other certification exams are much simpler, there are their own question bank practice, as long as the question bank practice can be very easy to pass.