Glossary, Lossary – ADC CUDA 3 User Manual
Page 595
C
G
LOSSARY
16 QAM
Modulation mode used by the CMTS. QAM uses both amplitude and 
phase modulation to encode multiple bits of data in one signaling 
element, thus achieving higher data transfer rates than just amplitude or 
phase modulation alone.
16 QAM encodes four bits per symbol as one of sixteen possible 
amplitude and phase combinations. 16 QAM refers to the number of 
discrete phase/amplitude states that are used to represent data bits.
64 QAM
A modulation mode used by the CMTS. 64 QAM uses both amplitude 
and phase modulation to encode multiple bits of data in one signaling 
element. 64 QAM encodes 6 bits per symbol as one of 64 possible 
amplitude and phase combinations.
256 QAM
A modulation mode used by the CMTS. 256 QAM uses both amplitude 
and phase modulation to encode multiple bits of data in one signaling 
element. 64 QAM encodes 8 bits per symbol as one of 256 possible 
amplitude and phase combinations.
A
Record that contains the IP address of the record’s owner. Since hosts may 
have multiple IP addresses, multiple A records may match a given domain 
name. 
Address Resolution 
Protocol (ARP)
A protocol for mapping an Internet Protocol address (IP address) to a 
physical machine address that is recognized in the local network. For 
example, in IP Version 4, the most common level of IP in use today, an 
address is 32 bits long. In an Ethernet local area network, however, 
addresses for attached devices are 48 bits long. (The physical machine 
address is also known as a Media Access Control or MAC address 
address.)