Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated: 1 00:00:00,000 --> 00:00:04,000 align:middle line:84% In this video, we're going to discuss Spanning Tree 2 00:00:04,000 --> 00:00:10,000 align:middle line:84% Spanning Tree was developed to stop a layer 2 loops occurring in switch environments. 3 00:00:10,000 --> 00:00:16,000 align:middle line:84% In transparent switching or transparent bridging which is what Ethernet uses 4 00:00:16,000 --> 00:00:22,000 align:middle line:84% redundant links introduce loops and Spanning Tree is used to stop those loops. 5 00:00:22,000 --> 00:00:25,000 align:middle line:84% Spanning Tree has been around for many years 6 00:00:25,000 --> 00:00:28,000 align:middle line:84% and there been multiple developments and enhancements. 7 00:00:28,000 --> 00:00:31,000 align:middle line:84% So this is one of the challenges that you’re going to face. 8 00:00:31,000 --> 00:00:35,000 align:middle line:84% There are different implementations and version of Spanning Tree 9 00:00:35,000 --> 00:00:38,000 align:middle line:84% and you'll need to know some of those differences. 10 00:00:38,000 --> 00:00:43,000 align:middle line:84% Spanning Tree are very important protocol in traditional networks 11 00:00:43,000 --> 00:00:48,000 align:middle line:84% and once again its primary purpose is to stop loops in the switch environment 12 00:00:48,000 --> 00:00:52,000 align:middle line:84% and not necessarily to stop them as quickly as we would like. 13 00:00:52,000 --> 00:00:54,000 align:middle line:84% Spanning Tree was developed many years ago 14 00:00:54,000 --> 00:00:59,000 align:middle line:84% originally being developed for bridges rather than switches 15 00:00:59,000 --> 00:01:01,000 align:middle line:84% and thus at times a very slow to converge. 16 00:01:01,000 --> 00:01:05,000 align:middle line:84% In other words, it takes a long time for traffic to be re-routed 17 00:01:05,000 --> 00:01:08,000 align:middle line:84% if there’s a change in the network topology. 18 00:01:08,000 --> 00:01:11,000 align:middle line:84% Spanning Tree was once again originally developed for bridges 19 00:01:11,000 --> 00:01:16,000 align:middle line:84% and bridges do their calculations in software rather than in hardware 20 00:01:16,000 --> 00:01:18,000 align:middle line:84% which is what switches do today. 21 00:01:18,000 --> 00:01:22,000 align:middle line:84% So in the past, slower convergence was fine 22 00:01:22,000 --> 00:01:27,000 align:middle line:84% but that’s a major problem in today’s environments, where we run Voice over IP 23 00:01:27,000 --> 00:01:32,000 align:middle line:84% or other protocols that require very quick convergence. 24 00:01:32,000 --> 00:01:37,000 align:middle line:84% Thus the original standard Spanning Tree or 802.1D Spanning Tree 25 00:01:37,000 --> 00:01:41,000 align:middle line:84% has been superseded by newer versions 26 00:01:41,000 --> 00:01:44,000 align:middle line:84% such as Rapid Spanning Tree and Multiple Spanning Tree. 27 00:01:44,000 --> 00:01:50,000 align:middle line:84% because Spanning Tree is of great importance for the CCNA certification 28 00:01:50,000 --> 00:01:52,000 align:middle line:84% as well as for real deployments 29 00:01:52,000 --> 00:01:56,000 align:middle line:84% I’m going to start off with original version of Spanning Tree 30 00:01:56,000 --> 00:02:02,000 align:middle line:84% 802.1D and then we'll build on those concepts looking at more and more 31 00:02:02,000 --> 00:02:07,000 align:middle line:84% complex topologies and other versions of Spanning Tree. 3811