Apple QuickTime Streaming Server Darwin Streaming Server manual N, O

N, O

NAT (Network Address Translation) A technique sometimes used so that multiple computers can share a single IP address.

open source A term for the cooperative development of software by the Internet community. The basic principle is to involve as many people as possible in writing and debugging code by publishing the source code and encouraging the formation of a large community of developers who will submit modifications and enhancements.

P

packet A unit of data information consisting of header, information, error detection, and trailer records. QTSS uses TCP, UDP, and IP packets to communicate with streaming clients.

pixel A single dot in a graphic image with a given color and brightness value.

playlist A set of media files in the QTSS or DSS media folder specified to play one after the other or in random sequence.

port A sort of virtual mail slot. A server uses port numbers to determine which application should receive data packets. Firewalls use port numbers to determine whether or not data packets are allowed to traverse a local network. "Port" usually refers to either a TCP or UDP port.

privileges Settings that define the kind of access users have to shared items. You can assign four types of privileges to a share point, folder, or file: read and write, read only, write only, and none (no access).

progressive download Movie data that is pushed via HTTP to the client. The movie can be viewed by the user as it is being transferred. This is not a form of media streaming.

protocol A set of rules that determines how data is sent back and forth between two applications.

proxy server A server that sits between a client and server and negotiates communication between those two hosts. The client and server only communicate with the proxy server and never interact with each other. There are proxy applications for many network protocols, including HTTP (for web traffic) and RTSP (for streaming traffic).

Q

qtaccess The name of the plain text access file that contains information about users and groups who are authorized to view media in the directory in which the access file is stored.

QTSS (QuickTime Streaming Server) A technology that lets you deliver media over the Internet in real time.

QuickTime A set of Macintosh system extensions or a Windows dynamic-link library that supports the composition and playing of movies.

Glossary 73