What is purpose of NAV?

What is purpose of NAV?

NAV means network allocation vector it is used for sensing a carrier on the transmission medium. • This vector holds a value this value is decremented periodically when the data is being transmitted; when the value is ‘0’ the channel is idle.

What is the need of CTS RTS and NAV?

RTS/CTS is a mechanism that performs NAV distribution & helps to prevent collisions from occurring. So when RTS/CTS is enabled on a STA, every time STA want to transmit a frame, it must perform RTS/CTS exchange prior to the normal data transmission.

What is PCF in networking?

Point coordination function (PCF) is a media access control (MAC) technique used in IEEE 802.11 based WLANs, including Wi-Fi. It resides in a point coordinator also known as access point (AP), to coordinate the communication within the network.

What is physical carrier sense?

Physical carrier sense is performed constantly by all Wi-Fi radios that are not transmitting or receiving. When a station performs a physical carrier sense, it is actually listening to the channel to see whether any other RF transmissions are occupying the channel.

What is the purpose of NAV network allocation vector also explain RTS and CTS?

After sending RTS, a NAV (RTS) is initialized, so that no other station attempts to transmit. The receiving station waits for a short inter – frame space (SIFS) and issues a clear to send (CTS). With the CTS, a NAV (CTS) is initialized. The sender waits for a SIFS and transmits its data frame.

Why NAV is used in MACA protocol?

To avoid collisions, handshaking protocols rely on a system parameter called the network allocation vector (NAV). The NAV contains information on the duration for which the channel will be busy and allows a neighboring node to stay silent for that duration.

Why are RTS and CTS used in IEEE 802.11 protocol?

RTS/CTS (Request To Send / Clear To Send) is the optional mechanism used by the 802.11 wireless networking protocol to reduce frame collisions introduced by the hidden node problem.

What is PCF and DCF?

DCF stands for distributed coordination function and PCF stands for Point coordination function. In this page we will see difference between DCF and PCF medium access types defined in IEEE 802.11 WLAN standard. These are the mechanisms for the implementation of CSMA/CA in Wireless LAN.

What is PCF in wireless LAN?

What is WIFI CCA?

The Clear Channel Assessment (CCA) is a mechanism for determining whether the medium is idle or not. The CCA includes carrier sensing and energy detection. The Carrier Sense (CS) mechanism consists of a physical CS and a virtual CS.

Which carrier sense method is used to detect and decode 802.11 transmissions?

Which carrier sense method is used to detect and decode 802.11 transmissions? B. The signal detect (SD) threshold is used to identify any 802.11 preamble transmissions from another transmitting 802.11 radio. The preamble is a component of the Physical layer header of 802.11 frame transmissions.

What is the importance of network allocation vector in the CSMA CA?

The network allocation vector (NAV) is a virtual carrier sensing mechanism that forms an important part of the carrier sense multiple access with collision avoidance (CSMA/CA). It is implemented in wireless network protocols, IEEE 802.11 and IEEE 802.16, which operates in the medium access control (MAC) layer.

What does network allocation vector ( NAV ) mean?

The network allocation vector (NAV) is a virtual carrier-sensing mechanism used with wireless network protocols such as IEEE 802.11 and IEEE 802.16 (WiMax). The virtual carrier-sensing is a logical abstraction which limits the need for physical carrier-sensing at the air interface in order to save power.

How is network allocation vector used in WiMAX?

The network allocation vector (NAV) is a virtual carrier-sensing mechanism used with wireless network protocols such as IEEE 802.11 and IEEE 802.16 (WiMax). The virtual carrier sensing is a logical abstraction which limits the need for physical carrier-sensing at the air interface in order to save power.

What is the maximum duration of the network allocation vector?

The network allocation vector can be considered as a counter that counts down to zero. The maximum NAV duration is the transmission time required by frame, which is the the time for which the channel will be busy. At the start of transmission of a frame, the NAV value is set to its maximum.

What is channel allocation in a computer network?

What is channel allocation in computer network? The network allocation vector (NAV) is a virtual carrier sensing mechanism that forms an important part of the carrier sense multiple access with collision avoidance (CSMA/CA).

https://www.youtube.com/watch?v=7LvkKVqDBhM