W7 - CLIENTS, SERVERS, NETWORKS, AND CLOUDS

Question 1

W7-1: (1) What is a COMPUTER NETWORK?

(2) What is the Internet?
(3) What is INTRANET?

Answer 1

(1) a SET of computers CONNECTED TOGETHER for the purpose of SHARING RESOURCES
(2) a NETWORK of peer networks sharing a vast range of information resources and services

(3) shared resources include file, print, DB, and web servers.
EX: VPN = Virtual Private Network extends a private intranet across the Internet via IP tunnelling.

Question 2

W7-2: Two-Tier Architecture — Client–Server Model

Answer 2

_ Server/Host Business centralized: multi user processing, data store, communication with other systems
_ Client is User Facing distributed: advanced presentation, user data management; tells server what to do

Question 3

W7-3: FTP: File Transfer Protocol

Answer 3

_ FTP is a simple client – server application
_ The protocol allows diverse server and client software to work with each other.

1. Client authenticates and makes a connection
2. Client navigates to directories on both sides
3. Client requests, Server sends or accepts file
4. Client (or Server) sends confirmation message to Server (or Client)

Question 4

W7-4: Three-Tier or N-Tier Architecture

Answer 4

_ In Software Development, The analog of three-tier: MVC (Model – View – Controller) architecture.
_ In overall systems development, 3-Tier Architecture is divided into 3 layers:
Tier 1/ Presentation Layer at Client (VIEW)
EX: HTML5, JavaScript, CSS
Tier 2/ Functionality Layer at Application Server (CONTROLLER)
EX: Java, .NET, C#, Python, C++
Tier 3/ Data Layer at Database Server (MODEL)
EX: MySQL, Oracle, PostgreSQL, SQL Server, MongoDB

Question 5

W7-5: Distributed Computing

Answer 5

a ‘cloud’ of small remote servers, PCs, mobile devices supporting a single system.
EX: Climate Prediction, SETI@home, Distributed Compute Labs

Question 6

W7-6: Cloud Computing

Answer 6

_ is the practice of “using a network of REMOTE servers on the Internet” to store, manage, and process data, rather than a LOCAL server or a personal computer
_ provides “shared infrastructure, dev platform, or applications, on demand.”
_ rapidly provisioned (and released) with minimal management effort. Low start up cost.

Question 7

W7-7: Cloud Computing – IaaS: Infrastructure as a Service

Answer 7

_ provides services such as networking, servers, storage space, and/or raw computing power to your client network.
_ High range of “scalability”
EX: Amazon Web Services (AWS).
Google Compute Engine (GCP)
_ your ISP is your IaaS for your Internet connection.

Question 8

W7-8: Cloud Computing – PaaS: Platform as a Service

Answer 8

_ PaaS does intelligent things with data you upload.
+ File/DB share, version, replicate, cache, synch.
+ APIs for many web services, blockchain BaaS
_ PaaS provides hosted software development stacks to create web applications.
+ Frameworks to build, debug, deploy, scale up/down.
EX: 1/ Windows Azure runs your ASP.NET applications
2/ Red Hat OpenShift on Red Hat OpenStack Platform
3/ Google App Engine, Box.com

Question 9

W7-9: Cloud Computing – SaaS: Software as a Service

Answer 9

_ provides the user with fully functioning web based applications with only a browser or small app. !
_ SalesForce CRM – the original SaaS.
EX: 1/ Google Apps, Microsoft Office 365, BigBlueButton
_ Streaming services for consumers

Question 10

W7-10: Peer to Peer and Blockchain need networks

Answer 10

_ Apeer-to-peer(P2P)networkis two or more systems sharing resources without using a central server (no central authority).
_ BitTorrent protocol for file sharing

_ Advantages: low cost, easy to install, and no need for skilled staff, expensive servers, high bandwidth

_ Disadvantages: difficulty of administration, issues of security + trust, performance, scalability, reliability
+ Blockchain addresses security + trust