3Com 7000 manual Channel

GLOSSARY 137

out-of-bandTransmission of auxiliary information e.g., management messages, over a medium other than that used by the system users.

P

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.

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.

point-to-multipointA one-way call or connection that has only one source, but may have call many destinations.

point-to-point call A two-way call or connection that has one source and one destination.

Protocol Data Unit A unit of data specified in a layer protocol and consisting of protocol (PDU) control information and layer user data.

PTSE PNNI Topology State Element. A collection of PNNI information that is flooded among all logical nodes within a peer group.

PVC Permanent Virtual Connection. A basic connection method that requires the user to define each connection manually.

Q

QoS (Quality of Service) Quality of service is defined on an end-to-end basis

in terms of the following attributes of the end-end-to-end ATM connection: Cell Loss Ration, Cell Transfer Delay and Cell Delay Variation.