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This section defines important Terms. 

The Advance Network Gateway Ethernet (ANG_EN) is a wall- (or rack-) 
mounted unit that is self-contained with power supply and all electronics. 
It provides internal field termination points to connect standard Advance 
Data Hiway cable “on one side” and Ethernet 10BaseT cabling 
(Unshielded Twisted Pair) “on the other side”. The Gateway unit requires 
120 VAC power wired directly to it. 

A data link level protocol comprising the OSI model’s bottom two layers. 
It is a broadcast networking technology that can use several different 
physical media, including twisted-pair cable and coaxial cable. Ethernet 
usually used CSMA/CD. TCP/IP is commonly used with Ethernet 
networks. 

The result of two or more LAN stations attempting to use the same 
transmission medium at the same time. Collisions are a normal 
occurrence on Ethernet. A properly functioning Ethernet will experience a 
relative small percentage of collisions. Typically the collision rate should 
be less than 5% of the available bandwidth. Most collisions occur during 
the preamble portion of the frame. Most Ethernet controllers 
automatically retry, up to 15 times, any packet that has a collision during 
transmission. (Except for Late Collisions) 

CRC is a method to detect errors. A number is derived from the data that 
will be transmitted. By recalculating the CRC at the remote end and 
comparing it to the value originally transmitted, the receiving node can 
detect errors. 

The name “DataNET” is used to mean the high-speed communication 
system inclusive of our application software. 

The term “Data Hiway” refers to the Advance Optichrom Network. The 
Advance Network Gateway and DataNET Gateway are used to bridge 
the Advance Optichrom network and the Advance DataNET network. 

 

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