, IP address and netmask set. Chapter 16: Multilayer Switches Now, with something active in VLAN 20, the VLAN 20 SVI comes up in the MSFC: MSFC-6509# sho ip int brief Interface IP-Address OK? Method Status Protocol Vlan20 10.20.20.1 YES manual up Multilayer Switch Models Cisco offers a variety of multilayer switch models. The line has become fuzzy, though, because routers like the 7600 series can now take some of the 6500-series switching modules. The 3800 series of routers also supports a small switching module capable of supporting multiple Ethernet interfaces. Still, there is no magic all-in-one device. You must choose either a switch with limited routing capabilities, or a router with limited switching capabilities. The dif- ference is primarily in how the system internals are designed, and what modules supported. A router is designed differently from a switch, though this is also becom- ing less true if you consider devices like the Gigabit Switch Router (GSR). A router is generally more WAN-centric, whereas a switch is usually more LAN-centric. There are no modules that allow T1 WAN connectivity for the 6500 switches. While you can put 6500 Ethernet modules in a 7500 router, the backplane capacity is not as high in the router as it is in the switch. Multilayer switches are divided by chassis type. On the lower end are the single rack unit (1-RU) models that are designed for wiring closets and small installations. Some of these switches can be stacked in a number of ways, depending on the model. Some 1-RU models have increased backplane speeds, and even support 10 Gbps uplinks. Next in the hierarchy are the small chassis-based switches. This group is composed of the models in the 4500 range. These switches are designed for larger wiring clos- ets, or even small core functions. They can support multiple power supplies and supervisors, and are designed for high-availability installations. The 6500 switches occupy the high end of the spectrum. Available in multiple chas- sis sizes, these switches are very popul