The National Science Fair

Media Review

TOPICS OF SIGNALS AND MEDIA REVIEW

FDDI:

The FDDI is a technology Token Ring. The sequence of media access to the stations this default. A station generates a special signal called the witness (token) that controls the broadcast rights. This token passing continuously through the network, a node to the next node. When a station has something to send, it captures the token, format the information structures of FDDI, and then placed in the physical environment. The data rate of FDDI is 100 Mbs, and supports up to 500 stations in a network.

DOSCIS:

It is a method to transport data through a plant cables (CATV) with QAM modulation and / or QPSK. In the United States, DOCSIS modems are certified by CableLabs, the regulatory organization that establishes and evaluates the estandares.CableLabs is a consortium of operators and experts in the cable industry.

Crosstalk:

The crosstalk occurs when signals from a cable interfering with adjacent cables. This usually happens when multiple cables together in a bunch. The use of twisted pair cables helps reduce crosstalk. The crosstalk often occurs at the point where the connector joins the cable. This phenomenon is known as paradiafonia (NEXT). If there are not many braided cables, the signals are broadcast to other peers. While the shield may help reduce the problems of crosstalk, the most effective method of prevention involves the connection of the connectors and careful maintenance of the twisted pairs.

FIBER OPTICS:
Fiber Optic – The optical signals propagate through wires called glass optical fiber. Losses in optical fibers’ The optical signals are susceptible to losses when small particles are trapped within the glass.