The network access layer is comprised of the data link layer and the physical layer, and it has the same functionality as in the osi reference model. Switches can be described as layer 2 devices, meaning that they operate using the mac address to direct frames. Configure arubaos switches with layer 2 technologies such as rstp and mspt, link aggregation, vlans, lldp, and device profiles. Training 2pack for mta exams 98366 and 98367 40366a. A router is connected to at least two networks and is located at gateways, the. Evpn to support layer 2 overlay within the data center fabric. Layer 2 switches basically do switching only, which means they operate using devices mac addresses to redirect the data packets from the source port to the destination port. A network switch also called switching hub, bridging hub, officially mac bridge is networking hardware that connects devices on a computer network by using packet switching to receive and forward data to the destination device a network switch is a multiport network bridge that uses mac addresses to forward data at the data link layer layer 2 of the osi model. This course is designed for individuals getting started with their extreme networks extremexos switching and routing solution. This section provides a broad overview of networking, covering the fundamental concepts needed to. Certification and learning hewlett packard enterprise. The series provides nonblocking gigabit per port performance and include either 2. Configure basic ip routing with static routes or ospf on arubaos switches. Again, this book tries to simplify a complex networking entity so use.
Layer 2 ethernet switches are not concerned with whether the packet contains ip, ipx, or appletalk, but only with where the mac address of the recipient end system resides. The following image, image 1 will serve as a reference for this discussion. Now that you have learned about the concepts behind layer 2 and layer 3 switching in some detail, you will focus on a starttofinish configuration of a relatively simple campus switching design in this chapter. Layer 3 network layer the layer that routers and ip addresses operate at layer 2 data link layer the layer that switches, mac addresses and arp reside at layer 1 physical layer. Fundamentals series learn all the basics of data centers, from components to cabling to. Cisco nexus 7000 series nxos configuration examples, release 5.
Basics of tcpip, switching, routing and firewalling. Ethernet is a local area network technology with end stations assigned unique 48bit addresses. This address is used by layer 2 to assist a device in determining whether a frame is addressed to it. At layer 2, we are concerned about the rules within one local areanetwork while at layer 3, the rules for operating in an internetwork result in more complexity. As we have learned, a vlan breaks up a physical layer 2 network into multiple, logical layer 2 networks. Hardwarebased layer 3 switches also use layer 3 information in forwarding decisions. A comprehensive introduction to all facets of mpls theory and practice helps networking professionals choose the suitable mpls application and design for their network provides mpls theory and relates to basic ios configuration examples the fundamentals series from cisco press launches the basis to readers for understanding the purpose, application, and management of technologies mpls has. The address in the frame is compared to the mac address in the device.
Bridges and switches are data communications devices that operate principally at layer 2 of the osi reference model. Study guide for mta 98366 networking fundamentals maleek taylor august 26, 2015. In order to move between these layer 2 networks, this traffic needs to be routed at layer 3. Understand switches transmission speed, number and type of ports, number of uplinks, speed of uplinks, managed or unmanaged switches, vlan capabilities, layer 2 and layer 3 switches and. When it comes to networking, layer 2 can be a very weak link. The integrated circuit can be generalized as silicon, metal, and dielectric stacked layer on layer to create signal paths for electrical signals to connect the components of the device. Layer 2 network architecture design and performance basic provides an overview of layer 2 technologies and how they can be used to support a variety of services. One layer above the physical layer is the data link layer. Ipx, or appletalk, but only with where the mac address of the recipient end. Available as classroom instructorled training, virtual instructorled training and selfpaced elearning.
Describe the function and operation of layer 2 switching. The chapter begins by looking at how data are received by a switch, followed by mechanisms used to switch data as efficiently as possible, and concludes with forwarding data toward their destinations. A layer 2 switch works with mac addresses only and does not care about ip address or any items of higher layers. When a destination exists on another network, the communication must be directed by a router to the other network2.
Difference between layer 2 switch and layer 3 switch. Relay are all examples of data link layer or layer 2 protocols. They break up one large collision domain into multiple smaller ones in a typical lan, all hosts are connected to. If you continue browsing the site, you agree to the use of cookies on this website.
Ethernet, 802 standards, broadcast domains and vlans. Traditional ethernet switches operate at the data link layer and are concerned with forwarding packets based on the layer 2 addressing scheme. Switches operate at the data link layer layer 2 and sometimes the network layer layer 3 of the osi reference model. A common protocol used at the data link layer is address resolution protocol arp, which requests the mac addresses of a host with a known ip address. Additionally, it can do static routing and dynamic routing. Chapter 2 introduces many of the concepts behind lan switching common to all switch vendors. A trunk can be configured between two or more switches, between a router and a switch, or between a switch and a host such as a server. Written by two ccie, david barnes and basir sakandar, this book shows all their expertise in the area managing to clearly explain layer2 and layer3 usage. Red font color or gray highlights indicate text that appears in the answer copy only. Securing layer 2 technologies vlan and trunking fundamentals in order to be able to properly secure vlans and trunks, you must understand the basics of them. When data is to be sent from one ethernet station to another, the data is first arranged in frames as shown in figure 2. Manage the software and configuration files on arubaos switches, and manage arubaos switches and aps with aruba airwave. A layer 2 switch requires mac address of nic on each network node to transmit data.
Chapter 2 basic switch concepts and configuration objectives. Fundamentals of computer networking and internetworking prof. Ip routers, ip addresses, dhcp, public and private addresses, network address translation and ipv6. The extremeswitching 200 series is an economical, fixedconfiguration family of gigabit ethernet layer 23 switches designed for enterprises, branch offices, and small to mediumsized businesses looking for key features in a flexible, yet easytomanage solution. In layer 2, communication can only occur among devices on the same network segment. Layer 2 network architecture design and performance. This layer helps to uniquely identify hosts beyond the subnets and defines the path which the packets will follow or be routed to reach the destination.
Layer 1 layer 2 layer 3 layer 4 layer 5 d descriptive model formed after tcpip protocols were devised d used in practice computer networks and internets module 1 33 spring, 2014. It details ethernet switching principles pb, pbb, and pbbte, and carrier ethernet services and identifies how layer 2 services pointtopoint and multipoint can be transported. Percy dias slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Because it may not be efficient to continue to add links as the number of vlans grows, the solution is trunking. Chapter 15 covers the core traffic management system mpls, and how mpls is used to implement vpns, classes of service, service integration and. Recall from chapter 1, networking basics, that frames carry data across the network and. Ethernet sits at layer 1 and 2 on the osi model, or in the link layer in the tcpip model, and the addressing model which sits at this layer is media access control, or mac addresses. Layer 2 switching or data link layer switching is the process of using devices mac addresses to decide where to forward frames. Now imagine a third vlan is added, which requires another physical link between the switches. If this is not possible, keep the diameter of the layer 2 switches small.
This layer takes the raw transmission data signal, pulses etc. Layer 3 switches that blend the internal hardware logic of switches and routers into a hybrid device also have been deployed on some enterprise networks. Conventional network switches operate at layer 2 data link layer of the osi model. These addresses are called media access control mac addresses. Cisco 200301 new content in bold network fundamentals. Layer 3 does a better job of controlling the spread of the outage in the network. Student should possess a working familiarity with lan concepts, including basic ethernet and tcpip. Historically, layer 2 switches emerged to alleviate the contention problem of shared media lans. Exam 98366 networking fundamentals, 2nd edition wiley. It does that by maintaining a mac address table to remember which ports have which mac addresses assigned. They learn mac addresses automatically by copying mac address of each frame received, or listening to devices on the network and maintaining their mac address in a forwarding table. A layer 3 switch, or multilayer switch, can do all the job that a layer 2 switch does.
The data link layer in system a, for example, communicates with the network layer of system a, the physical layer of system a, and the data link layer in system b. Switches and bridges are used for layer 2 switching. In a typical lan, all hosts are connected to one central device. A firm understanding of network fundamentals is essential to being able to secure a network or attack one. They break up one large collision domain into multiple smaller ones. The ohio state university raj jain 1b layering protocols of each layer have to perform a set of functions all alternatives for a row have the same interfaces choice of protocols at each layer is independent of those of at other layers. So while switches can send data from source devices to destination devices using layer 2 mac addresses, intervlan routing using ip addressing. Changing arp bindings requires manual intervention. A router is a device that forwards data packets along networks. One way to look at a localarea network is to say that all devices in that lan have a common layer 3 ip network address. The ohio state university raj jain 8 layer3 vlans q also known as virtual subnet q vlan membership implied by maclayer protocol type field and subnet field 123. Layer 3 switches the layer 3 switch functions at the network layer and performs the multiport, virtual lan, data pipelining functions of a standard layer 2 switch. Fundamentals of computer networking and internetworking.
It can also perform basic routing functions between virtual lans. Through several chapters, the authors try to convince the readers to use a different, more modern, approach to networks, like using layer3 switches at the distribution layer instead of. Free ccna network fundamentals day 1 in this video lecture, imran explains the fundamentals of networking. A layer 3 design has many positive and negative attributes, but it does have one big advantage.
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