ccna r&s best book

ccna r&s best book.. VLAN support, which allows you to create logical broadcast domains in Layer 2 networks (VLANs are discussed in more depth in Chapter 12) o Table 4.1 lists additional differences between the bridge and the switch.Exam Points Keep in mind the differences between bridges and switches listed in Table 4.1.Probably the biggest difference between bridges and switches is in performance. Bridges use software to exchange frames at frame rates of 10,000 to 50,000 frames per second (fps); switches use ASICs to perform the exchange in hardware.ASICs are specialized processors that have one task in the switching world, and that is to exchange frames at extremely fast speeds. For example, the Catalyst 2960 switch has a frame rate of 2.7 million coins s, which is 50 times faster than the fastest bridges! Note that the 2960 is a low-end switch; the Cisco Catalyst 6500 switch has a frame rate of 400 million f^s!4.3.1 Switching Method Onenother difference between a bridge and a switch is the way frames are switched. The switching method determines how the Layer 2 device receives, processes, and forwards frames. Bridges support only one switching method one store-and-forward, while switches support one, two, or three switching methods. The three possible switching methods supported by Layer 2 devices are as follows.. Store-and-forward; . Direct pass-through; .. Fragment-free (Fragment-free)These methods are discussed in the next few subsections.Table 4.1 Comparison of Bridges and SwitchesChapter 4 Bridges and Switches 71