Toshiba P000233790 Manual De Usuario

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Overview 
The PCX5000 provides you with high-speed data communications over the television cable network 
by following the widely accepted DOCSIS standard.  This standard, as defined by CableLabs™, 
offers a combination of high performance and interoperability among  all major  cable system 
operators in North America. 
 
How does the PCX5000 work? 
Digital signals are represented by high and low electrical voltage levels. The speed of how fast these 
levels can switch and still be transmitted is determined by the "bandwidth" of the transmission 
system. The pair of wires used in a telephone connection has a greatly limited bandwidth because of 
their electrical characteristics. When a device called a modem is connected between the computer 
output and the phone line, it generates an electrical wave whose strength and phase change in step 
with the highs and lows of the computer's digital output. It is because of the "smoothness" of the 
resultant signal that a higher data rate can be transmitted. 
 
A cable modem “ modulates” and “demodulates” electrical signals in the same way that the telephone 
modem does. However, since coaxial cable can transmit much higher  frequencies, cable modems 
are far more complex. None of the activity caused by the PCX5000 disturbs your regular cable TV 
reception. 
 
How does the PCX5000 connect to a computer? 
The 10/100 Ethernet connection, USB connection and 802.11b wireless connection used in this 
device are emerging as the most popular means of networking computers together and to the 
Internet.  
 
How does the PCX5000 differ from a stand-alone DOCSIS 
cable modem? 
The standalone cable modem is designed to connect one computer. The  PCX5000 is designed to 
connect multiple computers using 10/100 Ethernet, USB and 802.11b wireless interface.  For 
standalone cable modems, you typically need to purchase an additional networking device called a 
router to connect more than one computer  to the cable modem.  With the  PCX5000, all of your 
computers can share your high-speed connection. 
 
The PCX5000 also includes advance security features such as a Stateful Inspection firewall that can 
protect your personal information and your equipment from malicious damage by hackers.  The 
PCX5000  Stateful Inspection  firewall is intelligent enough to know what applications should be 
allowed to access your network, and those that should be excluded. 
 
What is DOCSIS? 
Data Over Cable Service Interface Specifications. DOCSIS defines interface requirements for cable 
modems involved in high-speed data distribution over a cable television network. On November 17, 
1997, Cable Television Laboratories, Inc. (CableLabs) and its members established a formal path of 
certification for cable modem equipment suppliers to obtain an interoperability seal for their products 
based on the DOCSIS specification. This certification process provides cable modem equipment 
suppliers with a fast, market-oriented method for attaining cable industry acknowledgment of 
compliance with DOCSIS.