ALERT

[FREE DEMO] Deploy Your Enterprise Cloud in Minutes

V.22

Definition - What does V.22 mean?

V.22 is an ITU Telecommunications Standardization Sector recommendation used for full duplex communication between two analog dial-up modems using phrase-shift keying modulation at 600 baud to carry data at around 1,200 or 600 bits per second. V.22 is a variation of the Bell 212 A modulation format.

V.22 is the first true world standard developed for half duplex communication at 1,200 bps and is used mainly in Europe and Japan. In the United States, the protocol is defined by the Bell 212 A. Modems that adhere to this standard and are used on generalized switched telephone networks (GSTN) and point-to-point circuits.

V.22 is pronounced as v-dot-twenty-two.

Techopedia explains V.22

The main characteristic features of modems using the V.22 standard are:

  • They enable duplex operation on two-wire GSTN and point-to-point leased circuits.
  • They include test facilities and scramblers.
  • They use frequency division for channel separation.
  • The modems use differential phase shift modulation for every channel with synchronous line transmissions at 600 bauds.

The V.22 recommendations provide three alternative configurations.

  • A configuration that supports 1,200 bps synchronous and 600 bps synchronous transmission
  • A configuration that supports 1,200 bps start-stop and 600 bps start-stop transmission
  • A configuration that supports all of the above configurations

Asynchronous mode selections are made during the handshake sequence and provide compatibility between the second and third configuration alternatives.

Data streams to be transmitted are divided into groups of two consecutive bits. Every bit is encoded as a phase change relative to the phase of the preceding signal elements. The bits at the receiver side are encoded and then reassembled in the correct order. The left-hand digit of the bit stream is the one that occurs first in the data stream as it enters the modulator portion of the modem after it has left the scrambler.

Techopedia Deals

Connect with us

Techopedia on Linkedin
Techopedia on Linkedin
Tweat cdn.techopedia.com
"Techopedia" on Twitter


'@Techopedia'
Sign up for Techopedia's Free Newsletter!

Email Newsletter

Join thousands of others with our weekly newsletter

Resources
The 4th Era of IT Infrastructure: Superconverged Systems
The 4th Era of IT Infrastructure: Superconverged Systems:
Learn the benefits and limitations of the 3 generations of IT infrastructure – siloed, converged and hyperconverged – and discover how the 4th...
Approaches and Benefits of Network Virtualization
Approaches and Benefits of Network Virtualization:
Businesses today aspire to achieve a software-defined datacenter (SDDC) to enhance business agility and reduce operational complexity. However, the...
Free E-Book: Public Cloud Guide
Free E-Book: Public Cloud Guide:
This white paper is for leaders of Operations, Engineering, or Infrastructure teams who are creating or executing an IT roadmap.
Free Tool: Virtual Health Monitor
Free Tool: Virtual Health Monitor:
Virtual Health Monitor is a free virtualization monitoring and reporting tool for VMware, Hyper-V, RHEV, and XenServer environments.
Free 30 Day Trial – Turbonomic
Free 30 Day Trial – Turbonomic:
Turbonomic delivers an autonomic platform where virtual and cloud environments self-manage in real-time to assure application performance.