Glossary
8820-A2-GN20-30
March 2001
GL-3
PEM
Power Entry Module. A module that provides 48V power isolation and distribution,
overcurrent protection, and power filtering and monitoring for the Hotwire 8820 GranDSLAM
chassis.
POTS
Plain Old Telephone Service. Standard telephone service over the PSTN with an analog
bandwidth of less than 4 KHz.
POTS splitter
A device that filters out the DSL signal and allows POTS frequencies to pass through.
PPP
Point-to-Point Protocol. A protocol for packet transmission over serial links, specified by
Internet RFC 1661.
PSTN
Public Switched Telephone Network. A network shared among many users who can use
telephones to establish connections between two points. Also known as dial network.
RADSL
Rate Adaptive Digital Subscriber Line. A technique for the use of an existing twisted pair line
that permits simultaneous POTS and high-speed data communication at adaptive
symmetric and asymmetric rates.
ReachDSL
A subscriber line technology providing up to 1 Mbps throughput. Compliant with
ANSI T1.417, ReachDSL guarantees a minimum rate of 256 kbps at 18 kft.
router
A device that connects LANs by dynamically routing data according to destination and
available routes.
SCM
Shelf Concentration Module. A circuit card that provides connectivity between DSL devices
and an ATM uplink.
SDSL
Symmetric Digital Subscriber Line. A technique for the use of an existing twisted-pair line
that permits high bandwidth, bidirectional transmission.
SIM
System Interface Module. A module that provides user interface connections on the front of
the Hotwire 8820 GranDSLAM chassis.
SN
Service Node. The endpoint modem at the customer premises, also known as a Remote
Termination Unit (RTU).
SNMP
Simple Network Management Protocol. Protocol for open networking management.
TCP
Transmission Control Protocol. An Internet standard transport layer protocol defined in
STD 7, RFC 793. It is connection-oriented and stream-oriented.
TCP/IP
Transmission Control Protocol/Internet Protocol. The dominant protocol in the worldwide
Internet, TCP allows a process on one machine to send data to a process on another
machine using the IP protocol. TCP can be used as a full-duplex or one-way simplex
connection.
TDM SDSL
Time Division Multiplexing Symmetric Digital Subscriber Line. A technique for the use of an
existing twisted-pair line that permits high bandwidth, bidirectional transmission.
Telnet
Virtual terminal protocol in the Internet suite of protocols. Allows the user of one host
computer to log into a remote host computer and interact as a normal terminal user of the
remote host.
terminal emulation
Software that allows a PC to mimic the signals of a specific type of terminal, such as a
VT100 or 3270, to communicate with a device requiring that terminal interface.
TFTP
Trivial File Transfer Protocol. A standard TCP/IP protocol that allows simple file transfer to
and from a remote system without directory or file listing. TFTP is used where FTP is not
available.
