You can take the exam at any time, just register and make an appointment about 3 days in advance. The test place is in the VUE test center. At present, there are only 14 test sites in China.
The exams of CCNP and CCNA are the same, only on the client side of the test center. You must bring your ID card and diploma or two identification documents, such as a credit card or driver's license. You also need to press your fingerprints and take photos. This is Cisco's latest fingerprint authentication system.