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Appendix E: Glossary
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HSIM-W6 Installation Guide
Network Layer —
Layer 3 of the OSI reference model that provides the protocol routing
function.
Node —
Refers to a termination point for communication links; entity that can access a network.
OSI —
Open System Interconnection. An international standard developed by ITU (formally
CCITT) and ISO (International Organization for Standardization) to facilitate data networking
multi-vendor interoperability. The OSI Reference Model defines seven layers, each providing
specific network functions.
Packet —
A group of data that includes a header and usually user data for transmission through a
network.
Ping (Packet Internet Groper) —
An echo message, available within the TCP/IP protocol suite,
sent to a remote node and returned; used to test the accessibility of the remote node.
PPP (Point-to-Point Protocol) —
A Data Link layer protocol that provides asynchronous and
synchronous connectivity between computer/network nodes. Includes standardization for security
and compression negotiation.
Q.921 —
ISDN Data Link layer specification for the user-to-network interface.
Q.931 —
ISDN specification for call set-up and signaling on ISDN connections.
Q.933 —
ITU Frame Relay Data Link Layer specification for UNI.
RFC —
Request for Comment. Documentation describing Internet communications
specifications (e.g., TELNET, TFTP). Often these RFCs are used to achieve multi-vendor
interoperability during implementation.
RJ11 —
Standard 4-wire connectors for telephone lines.
RJ45 —
Standard 8-wire connectors used for ISDN lines.
RIP (Routing Information Protocol) —
Protocols used in IP and IPX for broadcasting open path
information between routers to keep routing tables current.
Routing —
A Network layer function that determines the path for transmitting packets through a
network from source to destination.