Cầu ưu tiên (2 byte)-ưu tiên hoặc trọng lượng của một chuyển đổi trong mối quan hệ với tất cả các thiết bị chuyển mạch khác. Các lĩnh vực ưu tiên có thể có một giá trị từ 0 đến và mặc định 32768 (0x8000) trên tất cả các switch Catalyst. | 282 Chapter 12 Advanced Spanning Tree Protocol 10. Which of the following standards defines the MST protocol a. b. c. d. 11. How many instances of STP are supported in the Cisco implementation of MST a. 1 b. 16 c. 256 d. 4096 12. What switch command can be used to change from PVST to MST a. spanning-tree mst enable b. no spanning-tree pvst c. spanning-tree mode mst d. spanning-tree mst You can find the answers to the Do I Know This Already quiz in Appendix A Answers to Chapter Do I Know This Already Quizzes and Q A Sections. The suggested choices for your next step are as follows 10 or less overall score Read the entire chapter. This includes the Foundation Topics Foundation Summary and Q A sections. 11 or 12 overall score If you want more review on these topics skip to the Foundation Summary section and then go to the Q A section at the end of the chapter. Otherwise move to Chapter 13 Multilayer Switching. Rapid Spanning Tree Protocol RSTP 283 Foundation Topics Rapid Spanning Tree Protocol RSTP The IEEE Spanning Tree Protocol was designed to keep a switched or bridged network loop free with adjustments made to the network topology dynamically. A topology change typically takes 30 seconds where a port moves from the Blocking state to the Forwarding state after two intervals of the Forward Delay timer. As technology has improved 30 seconds has become an unbearable length of time to wait for a production network to failover or heal itself during a problem. The IEEE standard was developed to take s principle concepts and make the resulting convergence much faster. This is also known as the Rapid Spanning Tree Protocol RSTP . RSTP defines how switches must interact with each other to keep the network topology loop free in a very efficient manner. Like RSTP s basic functionality can be applied as a single or multiple instances. This can be done as the IEEE Multiple Spanning Tree MST covered in this chapter .