O

Open Data Link Interface (ODI)
ODI is a Novell-developed specification that enables multiple protocol support for a NIC.

open source
See freeware.

Open Systems Interconnection (OSI)
OSI began as a reference model, that is, an abstract model for data communications. However, now the OSI model has been implemented and is used in some data communications applications. The OSI model, consisting of seven layers, falls logically into two parts. Layers 1 through 4, the "lower" layers, are concerned with the communication of raw data. Layers 5 through 7, the "higher" layers, are concerned with the networking of applications.

operating wavelength
The wavelength of an optical signal (mode) is referred to as an operating wavelength. Wavelength determines the color of visible light, although network signals in optical fiber use infrared wavelengths that are invisible to the human eye.

optical carrier (OC)
OC is one of the optical signal standards defined by the SONET digital signal hierarchy. The basic building block of SONET is the STS-1 51.84-Mbps signal, chosen to accommodate a DS3 signal. The hierarchy is defined up to STS-48, that is 48 STS-1 channels, for a total of 2,488.32 Mbps capable of carrying 32,256 voice circuits. The STS designation refers to the interface for electrical signals. The corresponding optical signal standards are designated OC-1, OC-2, etc.