I

I/O

In computing, input/output or I/O (or informally, io or IO) is the communication between an information processing system (such as a computer) and the outside world, possibly a human or another information processing system.

View Source: http://en.wikipedia.org/wiki/Input/output

IMEI

The International Mobile Station Equipment Identity or IMEI is a number, usually unique, to identify 3GPP (i.e., GSM, UMTS and LTE) and iDEN mobile phones, as well as some satellite phones. It is usually found printed inside the battery compartment of the phone, but can also be displayed on-screen on most phones by entering *#06# on the dialpad, or alongside other system information in the settings menu on smartphone operating systems.

View Source: https://en.wikipedia.org/wiki/International_Mobile_Station_Equipment_Identity

IMSI

The International Mobile Subscriber Identity or IMSI is used to identify the user of a cellular network and is a unique identification associated with all cellular networks. It is stored as a 64 bit field and is sent by the phone to the network. It is also used for acquiring other details of the mobile in the home location register (HLR) or as locally copied in the visitor location register. To prevent eavesdroppers identifying and tracking the subscriber on the radio interface, the IMSI is sent as rarely as possible and a randomly generated TMSI is sent instead.

View Source: https://en.wikipedia.org/wiki/International_mobile_subscriber_identity

IsatData Pro

A global two-way short message service for machine-to-machine (M2M) communication. Enables companies to track and monitor their fixed or mobile assets, giving them increased visibility of business operations, enhanced efficiency, and greater safety and security for their assets, cargo and drivers – while lowering operational costs.

View Source: http://www.inmarsat.com/service/isatdata-pro/

ISDN

Integrated Services for Digital Network (ISDN) is a set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the traditional circuits of the public switched telephone network.

View Source: https://en.wikipedia.org/wiki/Integrated_Services_Digital_Network