Appendix C: Glossary

TFTP

Trivial File Transfer Protocol is a protocol used to download card images or other files

 

from an external TFTP server to the NVRAM of any installed cards, or to upload files

 

from an installed card to an external TFTP server.

trap receivers

PCs configured to receive SNMP traps (messages).

traps

Autonomous, interrupt-driven, SNMP messages sent from a managed node to a

 

network management station to indicate that an event has occurred.

UAS

UnAvailable Seconds is the number of seconds during which the line is unavailable.

UBR

Unspecified Bit Rate is an ATM traffic type used for LAN traffic. When network

 

congestion occurs, the data is stored in a buffer until it can be sent.

UDP

User Datagram Protocol is a transport protocol used to map inbound traffic (from a

 

remote IP address) to an internal (LAN) IP address. Uses a protocol port number for

 

the destination at the remote location.

upstream traffic

Communications from the Megabit Modem 420F to the 410F.

VCMUX

Virtual Channel Multiplexer-based encapsulation used for networks with large

 

numbers of virtual channels making it practical to carry a single protocol per virtual

 

channel.

VC

Virtual Channel is a logical connection in the ATM network over which ATM cells are

 

transmitted.

WAN

Wide Area Network is a network consisting of nodes located across a large

 

geographical area. Also, the connection between the Megabit Modem 410F and 420F.

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Megabit Modem 410F and 420F User Manual