Cabletron Systems SFCS-200BX Switch User Manual


 
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GLOSSARY
Physical Layer (PHY) Connection - an association established by the PHY
between two or more ATM-entities. A PHY connection consists of the concat-
enation of PHY links in order to provide an end-to-end transfer capability to
PHY SAPs.
PMD (Physical Medium Dependent) - a sublayer concerned with the bit
transfer between two network nodes. It deals with wave shapes, timing
recovery, line coding, and electro-optic conversions for fiber based links.
PNNI (Private Network Node Interface or Private Network-to-Network
Interface) - a protocol that defines the interaction of private ATM switches or
groups of private ATM switches
ping (Packet Internet Groper) - a program used to test reachability of desti-
nations by sending them an ICMP echo request and waiting for a reply.
Point-to-Multipoint Connection - a collection of associated ATM VC or VP
links, with associated endpoint 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 is sending
information without additional (higher layer) information. (See the following
note for Phase 1.)
3. The Leaf Nodes cannot communicate directly to each other with this con-
nection type.
Note: Phase 1 signalling does not support traffic sent from a Leaf to the Root.
Point-to-Point Connection - a connection with only two endpoints.
Primitive - an abstract, implementation-independent interaction between a
layer service user and a layer service provider.
PROM (Programmable Read-Only Memory) - a chip-based information stor-
age area that can be recorded by an operator but erased only through a physi-
cal process.
Protocol - a set of rules and formats (semantic and syntactic) that determines
the communication behavior of layer entities in the performance of the layer
functions.
Protocol Control Information - the information exchanged between corre-
sponding entities using a lower layer connection to coordinate their joint
operation.