Junos® OS For Dummies®, 2nd Edition

Chapter 11

Deploying an EX Switch

In This Chapter

• Using VLANs with Juniper EX Series switches
• Setting up the switch to connect LANs
• Creating LAN segments with Virtual LANs
• Interconnecting EX switches with Virtual Chassis
• Using the Layer 2 switch as a Layer 3 router

You may think that routers and switches are the same because you use them to connect to the Internet or to a network in your office or campus. But from a technological point of view, as shown in Chapter 10, they're different.

Remember, routers, routing protocols, and the Internet Protocol (IP) operate at Layer 3, the network layer, of the OSI protocol stack. They use IP addresses to route traffic, and — for Ethernet networks — to map these addresses to each network device's media access control (MAC) address, which is the Layer 2 hardware address of the device. Switches operate at Layer 2, the data-link layer, of the OSI protocol stack, so they use only the MAC address to forward traffic through the network.

This chapter concentrates on two key components in modern networks: VLANs and switches. We'll see how VLANs help make large arrays of networked devices more manageable, and how switches make everything look like a unified whole.