Data ParallelismData Parallelism means concurrent execution of the same task on each multiple computing core.Let’s take an example, summing the contents of an array of size N. For a single-core system, one thread would simply sum the elements [0] . . . [N − 1]. For a dual-core system, however, thread A, running on core 0, could sum the elements [0] . . . [N/2 − 1] and while thread B, running on core 1, could sum the elements [N/2] . . . [N − 1]. So the Two threads would be running in parallel on separate computing cores.Task ParallelismTask ... Read More

Data ParallelismData Parallelism means concurrent execution of the same task on each multiple computing core.Let’s take an example, summing the contents of an array of size N. For a single-core system, one thread would simply sum the elements [0] . . . [N − 1]. For a dual-core system, however, thread A, running on core 0, could sum the elements [0] . . . [N/2 − 1] and while thread B, running on core 1, could sum the elements [N/2] . . . [N − 1]. So the Two threads would be running in parallel on separate computing cores.Task ParallelismTask ... Read More

Amdahl’s LawSuppose, Moni have to attend an invitation. Moni’s another two friend Diya and Hena are also invited. There are conditions that all three friends have to go there separately and all of them have to be present at door to get into the hall. Now Moni is coming by car, Diya by bus and Hena is coming by foot. Now, how fast Moni and Diya can reach there it doesn’t matter, they have to wait for Hena. So to speed up the overall process, we need to concentrate on the performance of Hena other than Moni or Diya.This is ... Read More

Multicore programming helps to create concurrent systems for deployment on multicore processor and multiprocessor systems. A multicore processor system is basically a single processor with multiple execution cores in one chip. It has multiple processors on the motherboard or chip. A Field-Programmable Gate Array (FPGA) is might be included in a multiprocessor system. A FPGA is an integrated circuit containing an array of programmable logic blocks and a hierarchy of reconfigurable interconnects. Input data is processed by to produce outputs. It can be a processor in a multicore or multiprocessor system, or a FPGA.The multicore programming approach has following advantages ... Read More

In data communications and networking, orthogonal frequency-division multiplexing (OFDM) is a method of digital data modulation, whereby a single stream of data is divided into several separate sub-streams for transmission via multiple channels.OFDM uses the principle of frequency division multiplexing (FDM), where the available bandwidth is divided into a set of sub-streams having separate frequency bands. OFDM was introduced in 1966 by Chang at Bell Labs and was improved by Weinstein and Ebert in 1971.Working Principle of OFDMOFDM is a specialised FDM having the constraint that the sub-streams in which the main signal is divided, are orthogonal to each other. ... Read More

Complementary Code Keying (CCK) is a modulation technique deployed in wireless local area networks (WLANs) that follow IEEE 802.11b specification. CCK came into use in 1999 whereby it replaced the Barker code in wireless networks. CCK helps in attaining data rates higher than 2 Mbps, though at the cost of shorter ranges.Features of CCKCCK is used in wireless LANs to attain theoretical maximum data rates of 11 Mbps.CCK is implemented for transmission in the radio frequency range (RF band) of 2.4GHz – 2.4835GHz.CCK includes a pair of codes called chipping sequences which are complementary to each other. In complementary codes, ... Read More

Rate adaptation is a criteria that determines the performance of IEEE 802.11 wireless networks, or WiFi. Rate adaptation allows transmission to be done at different rates within the wireless network, depending upon the network conditions.In wireless networks, the signal may be strong or weak. Through rate adaptation technique, the data transfer date can be changed depending upon the signal strength, i.e. when the signal is strong, high data rates are adopted, while low data rates are adopted during weak signals.Rate Adaptation AlgorithmsIn traditional rate adaptation algorithms, the lowest permissible data rate was selected for data transfer. Though this ensured that ... Read More

IEEE 802.11 standard, popularly known as WiFi, lays down the architecture and specifications of wireless LANs (WLANs). WiFi or WLAN uses high frequency radio waves instead of cables for connecting the devices in LAN. Users connected by WLANs can move around within the area of network coverage.IEEE 802.11 ArchitectureThe physical layer architecture of IEEE 802.11 has the following components −Stations (STA) − Stations comprises of all devices and equipment that are connected to the wireless LAN. A station can be of two types −Wireless Access Point (WAP) − WAPs or simply access points (AP) are generally wireless routers that form ... Read More

Wireless LANs (WLANs) are wireless computer networks that use high-frequency radio waves instead of cables for connecting the devices within a limited area forming LAN (Local Area Network). Users connected by wireless LANs can move around within this limited area such as home, school, campus, office building, railway platform, etc.Most WLANs are based upon the standard IEEE 802.11 standard or WiFi.Components of WLANsThe components of WLAN architecture as laid down in IEEE 802.11 are −Stations (STA) − Stations comprises of all devices and equipment that are connected to the wireless LAN. Each station has a wireless network interface controller. A ... Read More

Carrier Ethernet is an application of Ethernet technology that allows network providers to offer Ethernet services to their customers and to use Ethernet technology. It enables Internet access and communication among local area networks (LANs) of business, academic, private and government organizations.The services and standards of carrier Ethernet have been defined by the Metro Ethernet Forum (MEF). MEF has also developed certification programs and it promotes the global adoption of carrier Ethernet.Carrier Ethernet versus EthernetThe primary attributes of Carrier Ethernet that differentiates it from Ethernet are −A carrier Ethernet network provides service to many organizations, while an Ethernet LAN renders ... Read More