Packet

Packet may refer to:

See also

Packet (container)

A packet is a small bag or pouch, made from paper, foil, or plastic film, often used to contain single-use quantities of foods or consumer goods such as ketchup or shampoo. Packets are commonly opened by making a small rip or tear in part of the package, and then squeezing out the contents.

Uses

Condiments distributed in packets include ketchup, mustard, mayonnaise, salad cream, HP sauce, relish, tartar sauce, vinegar and soy sauce. They provide a simple and low-cost way of distributing small amounts of condiment with ready-to-eat packaged food such as hot dogs, French fries, or hamburgers, and are common in fast food restaurants. The packets produce less contamination and mess than freely available condiments dispensed into small disposable cups or other containers, especially if the food will be in transit before dining. Potpourri fragrances are also sold in sachets. Potpourri sachet envelopes are filled with scented herbs and flowers or use vermiculite containing aromatic fragrance oil. These are known as potpourri wardrobe sachets. In Argentina and Uruguay, milk and yogurts are also sold in packets.

Network packet

A network packet is a formatted unit of data carried by a packet-switched network. Computer communications links that do not support packets, such as traditional point-to-point telecommunications links, simply transmit data as a bit stream. When data is formatted into packets, the bandwidth of the communication medium can be better shared among users than if the network were circuit switched.

A packet consists of control information and user data, which is also known as the payload. Control information provides data for delivering the payload, for example: source and destination network addresses, error detection codes, and sequencing information. Typically, control information is found in packet headers and trailers.

Terminology

In the seven-layer OSI model of computer networking, packet strictly refers to a data unit at layer 3, the Network Layer. The correct term for a data unit at Layer 2, the Data Link Layer, is a frame, and at Layer 4, the Transport Layer, the correct term is a segment or datagram. For the case of TCP/IP communication over Ethernet, a TCP segment is carried in one or more IP packets, which are each carried in one or more Ethernet frames.