C.Configuration Examples
C
This appendix contains information about how to configure:
•Virtual Local Area Networks (VLANs)
•Access Control Lists (ACLs)
•Differentiated Services (DiffServ)
•802.1X
•MSTP
•VLAN Routing with a Static Route
Virtual Local Area Networks (VLANs)
A local area network (LAN) can generally be defined as a broadcast domain. Hubs, bridges, or switches in the same physical segment or segments connect all end node devices. End nodes can communicate with each other without the need for a router. Routers connect LANs together, routing the traffic to the appropriate port.
A virtual LAN (VLAN) is a local area network with a definition that maps workstations on some basis other than geographic location (for example, by department, type of user, or primary application). To enable traffic to flow between VLANs, traffic must go through a router, just as if the VLANs were on two separate LANs.
A VLAN is a group of PCs, servers, and other network resources that behave as if they were connected to a single network
VLANs have a number of advantages:
•It is easy to do network segmentation. Users that communicate most frequently with each other can be grouped into common VLANs, regardless of physical location. Each group’s traffic is contained largely within the VLAN, reducing extraneous traffic and improving the efficiency of the whole network.