Server: A computer or device on a network that stores and manages certain resources. File servers typically store the audio and video content; database servers handle database queries and sales and billing information. Servers are often dedicated to one specific task.
Protocol: The rules and encoding specifications for sending data. The protocol also determines whether the network uses a peer-to-peer or client/server architecture.
Transmission Control Protocol allows two host servers or computers to connect and exchange data. It guarantees delivery and that packets are received in the same order they were sent.
IP: Internet Protocol specifies the format of packets and the addressing scheme. Most networks combine IP with a higher-level protocol, such as TCP, to establish a virtual connection between a destination and a source. It's similar to the postal system: You can address a letter and put it into the system, but there is no direct link between you and the addressee. TCP establishes a connection between two hosts so that they can send messages back and forth.
FTP: File Transfer Protocol defines how files are exchanged over the Internet. It uses TCP/IP protocols to enable the transfer.
Client/Server architecture: A network architecture in which each computer or process on the network is either a client or a server. Servers are powerful computers dedicated to managing disk drives (file servers) or network traffic (network servers). Clients are PCs or workstations on which users run applications. Clients rely on servers for resources, such as files, devices and even processing power.
Ethernet: A networking technology that supports data-transfer rates of 10 Mbps (megabits per second).
Fast Ethernet: A newer version of Ethernet, also called 100Base-T, supports data-transfer rates of 100 Mbps. The newest version, Gigabit Ethernet, supports data rates of 1 gigabit (1,000 megabits) per second.
Node: An individual computer on the LAN (see page 28). It has its own Computer Processing Unit (CPU) to execute programs and access data and devices on the LAN.
Peer-to-Peer Networking: Each node has equivalent responsibilities.
Proxy server: Intercepts all messages entering and leaving the network. The proxy server effectively hides the true network addresses.
Topology: The geometric arrangement of devices on the network. For example, devices can be connected in a ring or in a straight line.
Application gateway firewall: Applies security mechanisms to specific applications, such as File Transfer Protocol (FTP). It's very effective but can degrade performance.
A system to prevent unauthorized access to or from a private network. Firewalls can be implemented in hardware, software or a combination of both.
Packet-filter firewall: Looks at each packet entering or leaving the network and accepts or rejects it based on user-defined rules. Packet-filtering is fairly effective and transparent to users but is difficult to configure.
Circuit-level gateway firewall: Applies security mechanisms when a TCP connection is established. Once the connection has been made, packets can flow between the hosts without further checking.
Raid: Redundant Array of Independent (or Inexpensive) Disks refers to the use of two or more disks together. The goal is to improve performance and reliability, important features of any broadcast-related video server or storage system. There are different RAID levels, known as level 0, 1, 3 and 5. Level 0 has no redundancy while level 5 has the best performance and redundancy.
Metadata: Data about data. It describes how, when and by whom a particular set of data was collected, and how the data is formatted. It's useful in cataloging and finding video and audio content stored in file format.