A layer 2 switch or second layer is a network bridge that operates in the data link layer. A layer 2 can connect several small devices at work or at home. This is accomplished by having the bridge acquire the MAC addresses for all of the connected devices. Layer 2 differs from standard routers in this since because they use spanning tree bridges that require topologies that just one pathway for two points. Once the addresses have been obtained, they will forwarded in frames to the data link layer with the help of a method from layer 2.
Layer 3 operates within the physical layer of the Ethernet. Layer 3 has the ability to perform the normal functions of a router, but its most common ability is its awareness to multicast IP’s with the help of IGMP snooping. With the aide of the awareness, switches in layer 3 will have an efficiency increase by sending a multicast groups information to ports where it’s signaled by a group to be listened.
Routers are commonly used network devices that are specialized hardware that will forward information between networks. An overlay internetwork is created because the router has connected more than two data lines from various computer networks. When information is received through
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