IBM SG24-4817-00 Multipoint-to-multipoint connection. a, Pcmcia Personal Computer Memory Card

This soft copy for use by IBM employees only.

from the root node to the leaf nodes and a non-zero return bandwidth from the leaf nodes to the root node.

multipoint-to-multipoint connection. A

multipoint-to-multipoint is a collection of ATM VC or VP links and their associated endpoint nodes. Any information sent on the connection by a node is received by all of the other nodes. A receiving endpoint node cannot distinguish which other endpoint sent the information unless some higher layer information is present for the purpose.

N

network node interface. The interface between two

ATM switches.

NTSC (National Television Standard Committee). Video resolution: 525 rows x 700 vertical lines, 29.97 frames per second, transmitted as {fields/frame. Used in US, Japan,parts of South Africa.

O

OSPF (Open Shortest Path first). A link-state routing protocol specified by the IETF. Link-state routing protocols scale better than vector-distance routing protocol as RIP.

P

packet. In data communication, a sequence of binary digits, including data and control signals, that is transmitted and switched as a composite whole. Synonymous with data frame.

In ATM, ªAn information block identified by a label at layer 3 of the OSI reference model.º

PAL (Phase Alternation by Phase). Video resolution:625 rows x 700 vertical lines, 25 frames per second.

Standard used in most the world.

PCMCIA (Personal Computer Memory Card

International Association). An association involved in establishing hardware standards that are often associated with miniaturized peripherals.

PVC (Permanent Virtual Circuit). A logical

connection between end stations, defined through administrator configuration, that is established at all times that the network is operational.

physical layer. In the Open Systems Interconnection reference model, the layer that provides the mechanical, electrical, functional, and procedural means to establish, maintain, and release physical connections over the transmission medium.

point-to-multipoint connection. A point-to-multipoint connection is a collection of associated ATM VC or VP links and 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 node is sending the information without additional (higher layer) information.

3.Leaf nodes cannot communicate directly with each other.

ATM Forum Phase 1 signaling does not support traffic sent from a leaf to the root.

point-to-point connection. A connection that has 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.

private network to network interface. The interface between two switches, or between a switch and a switching subsystem. Also known as the private network to node interface.

protocol. (1) A set of semantic and syntactic rules that determines the behavior of functional units in achieving communication. (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.

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

R

RIP (Routing Information Protocol). A

vector-distance routing protocol.Versions of RIP are used with IP and IPX.

S

SAP (Service Advertising Protocol). An IPX protocol used to advertise the location of available services.

SECAM (Sequentielles Couleurs Avec Memoire).

Video resolution: 625 rows X 700 lines, 25 frames per second.

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