Distributed computing in the context of "Computational science"

A search engine is a software system that provides hyperlinks to web pages, and other relevant information on the Web in response to a user's query. The user enters a query in a web browser or a mobile app, and the search results are typically presented as a list of hyperlinks accompanied by textual summaries and images. Users also have the option of limiting a search to specific types of results, such as images, videos, or news.

For a search provider, its engine is part of a distributed computing system that can encompass many data centers throughout the world. The speed and accuracy of an engine's response to a query are based on a complex system of indexing that is continuously updated by automated web crawlers. This can include data mining the files and databases stored on web servers, although some content is not accessible to crawlers.

A smart device is an electronic device, generally connected to other devices or networks via different wireless protocols (such as Bluetooth, Zigbee, near-field communication, Wi-Fi, NearLink, Li-Fi, or 5G) that can operate to some extent interactively and autonomously. Several notable types of smart devices are smartphones, smart speakers, smart cars, smart cards, smart thermostats, smart doorbells, smart locks, smart refrigerators, phablets and tablets, smartwatches, smart bands, smart keychains, smart glasses, smart TV, and many others. The term can also refer to a device that exhibits some properties of ubiquitous computing, including—although not necessarily—machine learning.

Smart devices can be designed to support a variety of form factors, a range of properties pertaining to ubiquitous computing and to be used in three main system environments: physical world, human-centered environments, and distributed computing environments. Smart homes indicate the presence of sensors and some detection devices, appliances, and a database to control them.

In computer networking, a proxy server is a server application that acts as an intermediary between a client requesting a resource and the server then providing that resource.

Instead of connecting directly to a server that can fulfill a request for a resource, such as a file or web page, the client directs the request to the proxy server, which evaluates the request and performs the required network transactions. This serves as a method to simplify or control the complexity of the request, or provide additional benefits such as load balancing, privacy, or security. Proxies were devised to add structure and encapsulation to distributed systems. A proxy server thus functions on behalf of the client when requesting service, potentially masking the true origin of the request to the resource server.

Uploading refers to transmitting data from one computer system to another through means of a network. Common methods of uploading include: uploading via web browsers, FTP clients, and terminals (SCP/SFTP). Uploading can be used in the context of (potentially many) clients that send files to a central server. While uploading can also be defined in the context of sending files between distributed clients, such as with a peer-to-peer (P2P) file-sharing protocol like BitTorrent, the term file sharing is more often used in this case. Moving files within a computer system, as opposed to over a network, is called file copying.

Uploading directly contrasts with downloading, where data is received over a network. In the case of users uploading files over the internet, uploading is often slower than downloading as many internet service providers (ISPs) offer asymmetric connections, which offer more network bandwidth for downloading than uploading.

In computer science, a consistency model specifies a contract between the programmer and a system, wherein the system guarantees that if the programmer follows the rules for operations on memory, memory will be consistent and the results of reading, writing, or updating memory will be predictable. Consistency models are used in distributed systems like distributed shared memory systems or distributed data stores (such as filesystems, databases, optimistic replication systems or web caching). Consistency is different from coherence, which occurs in systems that are cached or cache-less, and is consistency of data with respect to all processors. Coherence deals with maintaining a global order in which writes to a single location or single variable are seen by all processors. Consistency deals with the ordering of operations to multiple locations with respect to all processors.

High level languages, such as C++ and Java, maintain the consistency contract by translating memory operations into low-level operations in a way that preserves memory semantics, reordering some memory instructions, and encapsulating required synchronization with library calls such as pthread_mutex_lock().

In computer science, interprocess communication (IPC) is the sharing of data between running processes in a computer system, or between multiple such systems. Mechanisms for IPC may be provided by an operating system. Applications which use IPC are often categorized as clients and servers, where the client requests data and the server responds to client requests. Many applications are both clients and servers, as commonly seen in distributed computing.

IPC is very important to the design process for microkernels and nanokernels, which reduce the number of functionalities provided by the kernel. Those functionalities are then obtained by communicating with servers via IPC, leading to a large increase in communication when compared to a regular monolithic kernel. IPC interfaces generally encompass variable analytic framework structures. These processes ensure compatibility between the multi-vector protocols upon which IPC models rely.

In computer science, concurrency refers to the ability of a system to execute multiple tasks through simultaneous execution or time-sharing (context switching), sharing resources and managing interactions. Concurrency improves responsiveness, throughput, and scalability in modern computing, including:

• Operating systems and embedded systems
• Distributed systems, parallel computing, and high-performance computing
• Database systems, web applications, and cloud computing

Leslie Barry Lamport (born February 7, 1941) is an American computer scientist and mathematician. Lamport is best known for his seminal work in distributed systems, and as the initial developer of the document preparation system LaTeX and the author of its first manual.

Lamport was the winner of the 2013 Turing Award for imposing clear, well-defined coherence on the seemingly chaotic behavior of distributed computing systems, in which several autonomous computers communicate with each other by passing messages. He devised important algorithms and developed formal modeling and verification protocols that improve the quality of real distributed systems. These contributions have resulted in improved correctness, performance, and reliability of computer systems.