Network Articles - Page 74 of 79

Tag identification layer of Electronic Product Code (EPC) Gen 2 lays down the method by which the readers can receive the identifiers from the tags. EPC Gen 2 (second generation) RFID (Radio Frequency Identification) network has two main components, tags and readers. RFID tags are affixed on objects with EPC encoded on them for identification. EPC helps to check identities of objects like inventory, assets and people, and track them. Readers are the intelligent part of the system that tracks the tags. The tag identification layer addresses the multiple access problem of getting messages from unknown number of tags.Working PrincipleIn ... Read More

Backscatter is a method that uses an incident radio-frequency (RF) signal to transmit data without a battery or power source. It employs passive reflection and modulation of the incoming RF signal, and converts it into tens or hundreds of microwatts of electricity, that can be encoded for data communications.It differs from other wireless communications since the communication is half duplex in nature, i.e. both the sender and receiver cannot transmit simultaneously. The mains advantage of backscattering is that it’s low energy requirements and low complexity of deployment.Architecture of backscatter communicationsA basic backscatter communication system has two main components: tags, and ... Read More

Physical layer of Electronic Product Code (EPC) Gen 2 defines method of transmission of bits across the network. EPC is a universal identifier encoded on RFID (Radio Frequency Identification) tags to check identities of objects like inventory, assets and people, and track them. The second generation of this technology, as laid down by EPCglobal Tag Data Standard, is called EPC Gen 2.EPC Gen 2 RFID network has two main components, tags and readers. Tags are affixed on objects that enables them to be identified or tracked. Readers are the intelligent part of the system that tracks the tags. The physical ... Read More

The Bluetooth radio layer is the lowest layer of Bluetooth architecture that corresponds to the physical layer of the OSI model. It lays down the physical structure and specifications for the transmission of radio waves.The position of the radio layer depicted in the following diagram −Characteristic Features of Bluetooth Radio LayerThe Bluetooth radio layer lays down the requirements of the Bluetooth transceiver device that communicates using Bluetooth technology.It defines air interface, frequency bands, frequency hopping specifications, and modulation techniques.This layer is responsible for moving data bits from the master device to the slave device, and vice versa.It is a low-power ... Read More

Bluetooth network technology connects mobile devices wirelessly over a short-range to form a personal area network (PAN). The Bluetooth architecture has its own independent model with a stack of protocols, instead of following the standard OSI model or TCP/IP model. The protocols in the Bluetooth standard can be loosely grouped into the physical layer, data link layer, middleware layer, and application layer as shown in the following diagram − Protocols in the Bluetooth Protocol Architecture Physical Layer − This includes Bluetooth radio and Baseband (also in the data link layer. ... Read More

Bluetooth communication networks are prone to signal interferences in environments where other wireless networks coexist. The problem is aggravated when they use the same frequency bands. Bluetooth technology and IEEE 802.11 networks, like Wireless LANs (WLANs) and WiFi, operate in the same unlicensed 2.4 GHz ISM (Industrial, Scientific, and Medical) radio band. In order to reduce the impact of these interferences, Adaptive Frequency Hopping (AFH) was introduced by Bluetooth Special Interest Group (SIG).In Adaptive Frequency Hopping, when a Bluetooth device is introduced in the network, it identifies the channels that are presently fixed for communication by WiFi or WLANs. It ... Read More

A piconet is a small Bluetooth network that connects mobile devices wirelessly over a short range of 10m radius, using ultra-high frequency (UHF) radio waves, to form a personal area network (PAN).A piconet can be formed by at most 8 stations, one of which is the master node and the rest slave nodes. Thus, it can accommodate a maximum of 7 slaves. The master node is the primary station that manages the small network. The slave stations are secondary stations that are synchronized with the primary station.Communication can take place between a master node and a slave node in either ... Read More

A scatternet is a type of Bluetooth network that is formed by the interconnection between two or more individual Bluetooth networks, called piconets. The devices in the scattered should be Bluetooth enabled so that they can communicate wirelessly over a short range of within 10m radius using ultra-high frequency (UHF) radio waves.In a scatternet, there must be at least two piconets. The nodes in a scatternet may be of three types −Master Node − It is the primary station in each piconet that controls the communication within that piconet.Slave Node − A slave is a secondary station in a piconet ... Read More

A Token Bus Network is a network protocol used to transmit data. In a Token Bus Network, a virtual ring is formed between nodes/stations and token is transferred from one station to another in a sequential manner. Each node in a Token Bus Network knows the address of its successor and predecessor and can transmit data if it has the token. A Token Ring Network is similar to a Token Bus Network but it works around the physical ring instead of a virtual ring. A token is passed from one node to another in a sequential manner and each node ... Read More

Both CSMA/CA and CSMA/CD are network protocols for transmission that operate in the Medium Access Control Layer, however there are significant differences in the way they operate. Read through this article to find out more about CSMA/CA and CSMA/CD and how they are different from each other.What is CSMA/CA?CSMA/CA is a network protocol for carrier transmission that stands for Carrier Sense Multiple Access with Collision Avoidance. It works in the same media access control layer as CSMA/CD. This protocol is effective before the collision.Algorithm of CSMA/CAThe algorithm of CSMA/CA is as follows −When a frame is ready, the transmitting station ... Read More