3Com 9000 Module Status LED, Multiplexing, Network to Network, Interface NNI, Partial Packet Drop

GLOSSARY 447

Module Status LED	An LED that indicates the system state of the ATM Interface Module.
multiplexing	A function within a layer that interleaves the information from multiple
	connections into one connection.
Network to Network	ITU-T-specified standard interface between nodes, typically ATM
Interface (NNI)	switches within the same network. The network uses E-IISP as its
	signaling protocol.
Partial Packet Drop	A procedure for discarding cells related to one user frame to minimize
(PPD)	the impact of congestion.
peer group	A set of logical nodes which are grouped for purposes of creating a
	routing hierarchy. PTSEs are exchanged among all members of the
	group.
peer group leader	A node which has been elected to perform some of the functions
	associated with a logical group node.
physical link	Any connection between two nodes in the lowest level hierarchy.
PNNI Routing Control	VCCs used for the exchange of PNNI routing protocol messages.
Channel
PNNI	Private Network to Network Interface. A routing information protocol
	that enables extremely scalable, full function, dynamic multi-vendor
	ATM switches to be integrated in the same network.
Port Status LED	LEDs that indicate the status of each ATM port.
Serial Link	The serial link handles the parallel-to-serial conversion for data
	transmission over the backplane.
Software State	LEDs that pinpoint the stage of the software execution at which the
Indicator LED	failure occurred.
Software Error LED	LEDs that light up in a binary pattern when a software error occurs.
traffic management	A mechanism for preventing congestion or other traffic flow problems
	in a network, by means of performing a set of actions for managing
	the traffic.
User Network	The interface, defined as a set of protocols and traffic characteristics,
Interface (UNI)	between the CPE (user) and the ATM network (ATM switch).