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Glossary Terms - O

ONC(tm) (Open Network Computing)

A distributed applications architecture promoted and controlled by a consortium led by Sun Microsystems. [Source: RFC 1208]

OSPF (Open Shortest Path First.)

A "Proposed Standard" IGP for the Internet. See IGP. [Source: RFC 1208]

OSI (Open Systems Interconnection)

An international standardization program to facilitate communications among computers from different manufacturers. See ISO. [Source: RFC 1208]

OSI Network Address (OSI Network Address)

The address, consisting of up to 20 octets, used to locate an OSI Transport entity. The address is formatted into an Initial Domain Part which is standardized for each of several addressing domains, and a Domain Specific Part which is the responsibility of the addressing authority for that domain. [Source: RFC 1208]

OSI Presentation Address (OSI Presentation Address)

The address used to locate an OSI Application entity. It consists of an OSI Network Address and up to three selectors, one each for use by the Transport, Session, and Presentation entities. [Source: RFC 1208]

TP0 (OSI Transport Protocol Class 0 (Simple Class))

This is the simplest OSI Transport Protocol, useful only on top of an X.25 network (or other network that does not lose or damage data). [Source: RFC 1208]

TP4 (OSI Transport Protocol Class 4 (Error Detection and Recovery Class))

This is the most powerful OSI Transport Protocol, useful on top of any type of network. TP4 is the OSI equivalent to TCP. [Source: RFC 1208]

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