QSC Audio RAVE 188 Star topology, Distributed star topology, Longer Distance Through Fiber

Star topology

Advantages: greater network size—up to 200 meters (656 feet); high reliability; readily expandable; uses standard Ethernet patch cables

Disadvantages: higher cost

Add nodes—i.e., RAVE units—to the previ- ous net layout and you have the classic star

topology. This name comes from the hub being at the center and the nodes radiating out from it like the points of a star. It doesn’t matter if the nodes are actually right next to one another while the hub is in another room—it’s still a star topology. You can

connect as many RAVE units as there are ports on the hub.

Star network topology

Distributed star topology

Advantages: greater network size; high reliability; readily expandable; uses standard Ethernet patch

cables

Disadvantages: higher cost

What do you do when you have more RAVE units than available hub ports? Add more hubs, of course. Most Fast Ethernet hubs now are stackable, either through an uplink port that lets you connect an additional hub to one already in the network, or through a backplane connection. The resulting network topolgy is called a distributed star, because it is made up of interconnected multiple stars. The maximum UTP cable length from hub to hub, or from hub to RAVE unit, is 100 meters (328 feet).

The example shown on the following page uses three hubs. The maximum size of this particular CobraNet network would be 400 meters (1312 feet), allowing two 100-meter cable runs among the three hubs, plus 100-meter cable runs on the end hubs.

You can expand the distances even further by daisy-chaining more hubs and cable segments. There are technical and practical limits to this strategy; see the section on network limitations for further information.

LONGER DISTANCE THROUGH FIBER

Sometimes a network may span long distances without any practical need for hubs distributed along the way. The computer networking industry, on whom we’re already relying for an economical and rugged transport medium, has an answer to this need also: fiber optics.

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