PTT

PTT may refer to:

Chemistry and medicine

Communication and technology

Switch

In electrical engineering, a switch is an electrical component that can break an electrical circuit, interrupting the current or diverting it from one conductor to another. The mechanism of a switch may be operated directly by a human operator to control a circuit (for example, a light switch or a keyboard button), may be operated by a moving object such as a door-operated switch, or may be operated by some sensing element for pressure, temperature or flow. A relay is a switch that is operated by electricity. Switches are made to handle a wide range of voltages and currents; very large switches may be used to isolate high-voltage circuits in electrical substations.

Description

The most familiar form of switch is a manually operated electromechanical device with one or more sets of electrical contacts, which are connected to external circuits. Each set of contacts can be in one of two states: either "closed" meaning the contacts are touching and electricity can flow between them, or "open", meaning the contacts are separated and the switch is nonconducting. The mechanism actuating the transition between these two states (open or closed) can be either a "toggle" (flip switch for continuous "on" or "off") or "momentary" (push-for "on" or push-for "off") type.

PTT (Turkey)

Ptt, abbreviation for Turkish: Posta Telgraf Teşkilatı, is the national post and telegraph directorate of Turkey. Formerly, the organization was named (Turkish: Posta Telgraf Telefon). After the privatization of the telephone telecommunications service business, the directorate was renamed, keeping its acronym. It is headquartered in Ankara. It is known as TURKISH POST internationally.

History

On October 23, 1840, Ottoman Ministry of Posts was established. In 1855, first telegraph service and in 1909 first telephone service were put into use. In the same year the name of the ministry was changed to Posta Telgraf Telefon ("Posts, Telegraph and Telephone" or PTT for short) a name which was used for 86 years. After Turkish Republic replaced the Ottoman Empire in 1923, the ministry became a general directorate of the Republic. In 1995 the telephone and other telecommunication services were transferred to newly founded Turk Telecom (which was soon privatized). Accordingly, the directorate was renamed as "Organization of Post and Telegraph" (Turkish: Posta Telgraf Teşkilatı). Thus the former acronym PTT is kept.

Mpls

Mpls or MPLS may refer to:

Minneapolis

Minneapolis (ⁱ/ˌmɪniˈæpəlɪs/) is the county seat of Hennepin County, and larger of the Twin Cities, the 14th-largest metropolitan area in the United States, containing approximately 3.8 million residents. As of 2016, Minneapolis is the largest city in the state of Minnesota and 46th-largest in the United States with 407,207 residents. Minneapolis and Saint Paul anchor the second-largest economic center in the Midwest, behind Chicago.

Minneapolis lies on both banks of the Mississippi River, just north of the river's confluence with the Minnesota River, and adjoins Saint Paul, the state's capital. The city is abundantly rich in water, with twenty lakes and wetlands, the Mississippi River, creeks and waterfalls, many connected by parkways in the Chain of Lakes and the Grand Rounds National Scenic Byway. It was once the world's flour milling capital and a hub for timber, and today is the primary business center between Chicago and Seattle, with Minneapolis proper containing America's fifth-highest concentration of Fortune 500 companies. As an integral link to the global economy, Minneapolis is categorized as a global city.

Multiprotocol Label Switching

Multiprotocol Label Switching (MPLS) is a type of data-carrying service for high-performance telecommunications networks that directs data from one network node to the next based on short path labels rather than long network addresses, avoiding complex lookups in a routing table. The labels identify virtual links (paths) between distant nodes rather than endpoints. MPLS can encapsulate packets of various network protocols, hence its name "multiprotocol". MPLS supports a range of access technologies, including T1/E1, ATM, Frame Relay, and DSL.

Role and functioning

MPLS is a scalable, protocol-independent transport. In an MPLS network, data packets are assigned labels. Packet-forwarding decisions are made solely on the contents of this label, without the need to examine the packet itself. This allows one to create end-to-end circuits across any type of transport medium, using any protocol. The primary benefit is to eliminate dependence on a particular OSI model data link layer technology, such as Asynchronous Transfer Mode (ATM), Frame Relay, Synchronous Optical Networking (SONET) or Ethernet, and eliminate the need for multiple layer-2 networks to satisfy different types of traffic. MPLS belongs to the family of packet-switched networks.