To prevent loops, spa places some interfaces into forwarding state and some interfaces into blocking state. This webcast shows you the stp topics for which youre responsible on the ccna rs 200125 or icnd2 200105. Stp uses the spanning tree algorithm spa to create a topology database of the nework. This section describes how spanningtree features work. All the ports in forwarding state are considered to be in the current spanning tree. One big disadvantage of stp is the low convergence which is very important in switched network. Configuring pervlan spanning tree protocol free ccna. The st transitions are logged in the format shown in figure. How does stp decides in which state to port will be placed.
Make sure switch grasshopper is the root bridge for vlan 40, switch butterfly should be the backup in case switch butterfly fails. Rapid spanning tree protocol rstprstp is defined in ieee 802. The spanning tree protocol is a layer 2 protocol used to avoid loops in a switched network. Spanning tree protocol this document descibes spanning tree protocol stp in a wireless environment. Cisco 3200 series wireless mic software configuration guide. Digital equipment corporation created a protocol called spanning tree protocol stp to prevent broadcast storms and network loops at layer 2. Spanning tree basic functions now including rstp 802. Now two switches offer the transparent bridging function in parallel. This question brings together the concepts of switching, vlan virtual lans, stp spanning tree protocol and redundancy all in one.
I will be concentrating on the main topics covered in the ccna icnd 2 exam. Quizlet flashcards, activities and games help you improve your grades. Be prepared to configure an interface, setup a routing protocol and diagnose problems with interface and routing configuration without the use of the cisco context help system found in the real routers and switches. Spanningtree protocol stp is a layer 2 protocol that utilizes a specialpurpose algorithm to discover physical loops in a network and effect a logical loopfree topology. The election decides which switch will become the root bridge, as. To overcome this problem, in 2001, the ieee with document 802. The spanning tree protocol is a link management protocol that is designed to support redundant links while at the same time preventing switching loops in the network. The root bridge on a lan is selected by an election. Spanningtree protocol, or stp, prevents switching loops in the layer 2 portion of our network. The original stp was developed by radia perlman while working for dce back in 1990. With stp in place, you can have redundant links between switches in order to provide redundancy. For a layer 2 network to function properly, only one active path can exist between any two stations.
Root selection varies depending on the bid of each switch in your lab. It has some similarities with cisco systems multiple instances spanning tree. Ccna routing and switching icnd2 200105 official cert. Spanning tree protocol stp is a layer 2 protocol that runs on bridges. Spanning tree protocol vs rapid spanning tree protocol. It is quite useful and should be enabled on the switch interfaces. A beginners tutorial on the function and purpose of stp spanning tree protocol in a local area network. It is a free guide from neil anderson who created a new guide. Cisco spanning tree protocol guide stp examples and. Ccna course gives you the basic knowledge to operate a computer network. Free cisco ccna lab guide pdf from neil anderson esx. Spanning tree protocol stp is a network protocol designed to prevent layer 2 loops.
The specification for spanning tree protocol is 802. Root selection varies depending on the bid of each switch in your lab resulting in varying outputs. Links that will cause a loop are put into a blocking state. The spanning tree algorithm places each bridgeswitch port in either a forwarding state or a blocking state. Spanning tree protocol stp ensures a loopfree topology in a local area network lan made up of switches. Before we talk about spanning tree protocol, lets organize the different variants of stp. We decided to put together this free ccna study guide after we received a large number of requests from our visitors for free ccna training. Mst is commonly used in extremely large networks where running pvst would tax switch resources. In discussing the spanning tree protocol here, i will try to be as practical about it as possible. I discuss how stp mitigates layer 2 loops and layer 2 broadcast storms. As layer 2 networks grew, it quickly became evident that a system to prevent loops was needed if lans were to continue to function. In this sample chapter from scaling networks v6 companion guide, explore potential redundancy problems, symptoms, and protocols to manage them.
By reading this course, you will acquire the necessary information and concepts about ccna. Spanning tree protocol study guide by etoner includes 35 questions covering vocabulary, terms and more. One of the topics on the ccna rs version 3 exam is spanning tree protocol stp. Cisco ccna prep spanningtree protocol stp section 1. It is typical that you will see a topology similar to the sample below on your cisco certified network associate 200120 ccna exam. Multiple spanning tree multiple spanning tree protocol mstp network organized in regions regions have their own multiple spanning tree instances spanningtree topologies vlans are associated to mstis one common spanning tree cst for the entire network mstp based on rstp rapid stp. Multiple spanning tree protocol can have multiple vlans all with one spanning tree instance. Switches running stp will build a map or topology of the entire switching network.
Ccna routing and switching 200125 complete video course more than 25 hours of video instruction overview ccna routing and switching 200125 complete video course is a comprehensive training course that brings cisco ccna exam topics to life through the use of realworld demonstrations, animations, live instruction, and configurations, making. The output shown in this lab is based on cisco 2960 switches. Observe and explain the default behavior of spanning tree protocol stp, 802. Free cisco certified network associate ccna online tutorials and study guides. Ccna in 21 hours 12 about this book about this book this ccna book offers you an easy, fast and precise understanding of the 640802 ccna syllabus. Understanding and configuring spanning tree protocol stp cisco. The collective set of forwarding ports creates a single path over which frames are sent between ethernet segments.
The message that a switch sends, allowing the formation of a loop free logical topology, is called a. Spanning tree is not doing what its supposed todo because we have not gone in thereand actually created the configuration forthe pervlan spanning tree, so thatswhat were going to do. Whilst it is quite feasible that you could pass using just the information and links contained within this free guide, it is more of an introduction to the ccna course, for you to evaluate. Stp is a layer 2 link management protocol that provides path redundancy while preventing loops in the network. Configuring multiple spanning tree protocol mstp free. Each switch running stp passes information in a format known as bridge protocol data units. Free cisco certified network associate routing and switching ccna routing and switching online tutorials and study guides. In this post, instead of detaily talk about stp spanning tree protocol, we will focus on a basic switching loop topology and how stp mechanism helps to avoid this switching loop. Rebuilding the multicast entries with cgmp and spanning tree topology changes. Network redundancy is a key to maintaining network reliability. Spanning tree protocol is a layer 2 protocol that works on bridges and switches. You are not allowed to use the spanningtree root command. This is the first in a series of posts on spanning tree, in this post i will be describing the need for spanning tree protocol stp in modern lan environments.
Hi guys, this post got awarded best publication at the cisco support community. Ccna in 21 hours about this book introduction this book gives a basic illustration for ccna cisco certified network associate, 640802 syllabus, which is a prerequisite certificate for most of the cisco certifications. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Cisco ccnp switch implementing spanning tree cisco ccnp switch redundant topology. Icnd2 200101 study guide ccna section i 21% lan switching technologies 1.
Stp overview stp is a layer 2 link management protocol that prov ides path redundancy while preventing loops in the network. Stp blocks some ports on switches with redundant links to prevent broadcast storms and ensure loopfree topology. If you have not yet registered, you will be prompted to register, before proceeding to access this content. This content is only accessible by registered users. Stp is on by default, but it only really comes alive when we have two or more switches interconnected with each other. Lesson 101 what is spanning tree protocol stp lesson 102 what is bridge protocol data unit bpdu frame. It vigilantly monitors the network to find all links, making sure that no loops occur by blocking any redundant ones. Change the hello timer on all switches for vlan 10 to 4 seconds. Spanningtree protocol stp a layer 2 switch, which functions as a transparent bridge, offers no additional links for redundancy purposes. Stp uses the spanningtree algorithm spa to create a topology database of the nework. Spanning tree protocol stp spanning tree protocol stp was developed to prevent the broadcast storms caused by switching loops.
The multiple spanning tree protocol mstp and algorithm, provides both simple and full. It is desirable to have redundant links in a switched lan so that a single link failure cannot interrupt normal operation of the network. Rules for mapping and tunnel as follows an exact specification of bpdu handling is given in section. On each switch, display the spanning tree table with the show spanningtree command. Ccna 200120 chapter 2 spanning tree protocol implementation. The spanningtree protocol requires network devices to exchange messages to detect bridging loops. Stp or spanning tree protocol is a protocol used on switches that prevents layer 2 switching loops and layer 2 broadcast storms. Before the introduction of vlans, the stp spanning tree protocol was in charge of establishing a. This is very necessary in large networks that are designed to have redundancy like backup switches and multiple paths across the network. Stp creates a loopfree tree structure consisting of leaves and branches that span the entire layer 2 network. Spanning tree protocolsome links below may open a new browser window to display the document you selected. Stp will identify if there are any loops, and then disable or block.
Cisco ccna spanning tree protocol stp spanning tree protocols stps main task is to stop network loops from occurring on your layer2 network bridges or switches. Welcome to the pervlan spanning tree lab,and as you can see already by looking at the labthat theres a switching loop thats occurring. Configure and troubleshoot cisco spanning tree stp. Free cisco certified network associate ccna online. Spanning tree protocol is a bridge protocol that enables a learning bridge to dynamically work around loops in a network topology by creating a spanning tree.
Understanding spanning tree protocol this section describes how spanningtree features work. This document descibes spanning tree protocol stp in a wireless environment. Spanningtree protocol stp premium ccna exam questions. Configure and troubleshoot cisco spanning tree stp learn how to configure stp, portfast and bpduguard on cisco switches free ccna course handson lab networking fundamentals switching troubleshooting written by alessandro maggio.
Multiple spanning tree protocol gives you the ability to configure a hierarchical spanning tree topology where you have a common spanning tree instance known as the cist, technically instance 0 in mst configuration mode. Introduction to stp, spanning tree protocol, broadcast storm, topological loop, switch macaddress table corruption,stp pdf file download, pdf file download, ethernet bridge, ethernet switch,layer 2 topological loop,ieee 802. Bpdu table info and stp bpdus show a deeper resume of the mstp bpdu format and, besides. Mohamed salem is a communication engineer and an it professional. When you connect two or more layer 2 devices, an election is run to designate the root bridge. Spanning tree protocol ccnax 200120 ccna practice tests. Spanning tree protocol stp in packet tracer part 1. Rapid spanning tree protocol rstp, which significantly reduces the convergence time after a topology change occurs in the network.
530 683 1034 1195 1659 82 204 1334 118 983 1252 1274 486 1256 1282 319 1122 851 1273 1307 340 515 801 683 362 115 906 1235 657 1610 280 287 1056 549 1187 172 1642 1068 109 1162 492 621 736 784 872 298 900 381 102