layered-system architecture

layers

logical separations of a software application

tiers

physical separations of a software application

server

a process implementing a specific service (file systems service or a database service)

client

a process that requests a service from a server by sending it a request and subsequently waiting for the server’s reply

request-reply behavior or client-server interaction

connectionless protocol through a reliable network, connection-oriented protocol (WAN)

two-tiered architecture

client then database and application server

three-tiered architecture

organizes applications into logical and physical computing tiers

presentation tier

user interface

logic or application tier

where data is processed

data tier

where application _ is stored and managed

network file system

sun microsystems for unix; comes with a communication protocol that allows clients to access the files stored on a server

remote file systems

clients are offered transparent access to a file system that is managed by a remote server; client is offered only an interface containing various file operations, but the server is responsible for implementing those operations.

upload/download model

file transfer protocol, a client can _ delete, rename, move and copy files on a server

virtual file system

operations on the interface are either passed to a local file system, or passed to a separate component known as the NFS client, which takes care of handling access to files stored at a remote server; communications are done through RPCs

the web

documents turn from being purely static and passive to dynamically generated content; supports services instead of just documents

uniform resource locator

specifies where a document is located by embedding the DNS name of its associated server along with a file name by which the server can look up the document in its local file system; specifies the application-level protocol for transferring the document across the network

browser

accepts input from a user mostly by letting the user select a reference to another document, which it then subsequently fetches and displays (HTTP, HTML, and Javascript)

peer-to-peer networks

fundamental aspect of distributed systems, where computers communicate directly with each other, rather than through a central server; operate on the principles of decentralization and equality where each node in the network can act both as a client and a server, sharing resources like processing power, storage, or files with other nodes.

symmetrically distributed system architectures

structured peer-to-peer systems, unstructured peer-to-peer systems, hierarchically organized peer-to-peer networks

hybrid system architectures

cloud computing, edge-cloud architecture, blockchain architecture