IBM 8265 Nways ATM Switch, User Manual, Page: 184 / 192

peer group identifier. A string of bits that is used to
unambiguously identify a peer group.
peer group leader. A node which has been elected to
perform some of the functions associated with a logical
group node.
peer group level indicator. The number of significant
bits in the peer group identifier of a particular peer
group. group.
permanent virtual connection (PVC). (1) In X.25 and
frame-relay communications, a virtual connection that
has a logical channel permanently assigned to it at
each data terminal equipment (DTE). Call-establishment
protocols are not required. Contrast with
switched virtual
connection (SVC). (2) The logical connection between
two frame-relay terminating equipment stations, either
directly or through one or more frame-relay frame
handlers. A PVC consists of one or more PVC
segments.
PING. Packet Internet Groper.
PNNI. Private-Network-Network-Interface. A routing
information protocol that enables extremely scalable, full
function, dynamic multi-vendor ATM switches to be
integrated in the same network.
PNNI routing domain. A group of topologically
contiguous systems which are running one instance of
PNNI routing.
PNNI topology state element (PTSE). A collection of
PNNI information that is flooded among all logical nodes
within a peer group.
point-to-multipoint connection. A collection of
associated ATM VC or VP links, with associated
end-point nodes, with the following properties:
1. One ATM link, called the root link, serves as the
root in a simple tree topology. When the root node
sends information, all of the remaining nodes on the
connection, called leaf nodes, receive copies of the
information.
2. Each of the leaf nodes on the connection can send
information directly to the root node. The root node
cannot distinguish which leaf node is sending
information without additional (higher layer)
information.
3. The leaf nodes cannot communicate directly to each
other with this connection type.
point-to-point connection.. A connection with only
two end-points.
port. (1) An access point for data entry or exit. (2) A
connector on a device to which cables for other devices
such as display stations and printers are attached.
Synonymous with
socket. (3) A PHY entity and a PMD
entity in a node, together creating a PHY/PMD pair, that
may connect to the fiber media and provide one end of
a physical connection with another node.
protocol. (1) A set of semantic and syntactic rules
that determines the behavior of functional units in
achieving communication. (I) (2) In SNA, the meanings
of and the sequencing rules for requests and responses
used for managing the network, transferring data, and
synchronizing the states of network components. (3) A
specification for the format and relative timing of
information exchanged between communicating parties.
PTSE. PNNI Topology State Element.
PVC. Permanent virtual connection.
Q
QOS. Quality of service
quality of service (QOS). A set of communication
characteristics required by an application. Each QOS
defines a specific transmission priority, level of route
reliability, and security level. Each QOS also defines
whether the sessions are interactive.
R
RAIG. Resource Availability Information Group
RAM. Random access memory.
random access memory (RAM). A computer’s or
adapter’s volatile storage area into which data may be
entered and retrieved in a non-sequential manner.
remote. (1) Pertaining to a system, program, or device
that is accessed through a telecommunication line.
(2) Contrast with
local.
request for comments (RFC). In Internet
communications, the document series that describes a
part of the Internet suite of protocols and related
experiments. All Internet standards are documented as
RFCs.
resource availability information group (RAIG). The
RAIG contains information that is used to attach values
of topology state parameters to nodes, links, and
reachable addresses. The topology state parameters
are maximum cell rate, available cell rate, administrative
weight, and cell delay variation.
RFC. Request for Comments.
router. An attaching device that connects two LAN
segments, which use similar or different architectures,
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IBM 8265: User's Guide