IST 346 Exam #4
What is email?
A means to exchange electronic messages and data on the internet.
Anatomy of Email - components
APIs SMTP, MIME, Various RFC's Protocols IMAP4, POP3,SMTP, IMAPS Components MUA, MTA, Delivery Agent (MDA), Access agent (AA), Message Store.
Mobile Device Management Systems
Control which apps can be launched / accessed. Remotely install apps on devices.
The World-Wide Web
Information System on the Internet for displaying content resources.
Which programming languages would one need to know to write mobile apps on Android and iOS?
Iphone:Swift Android:Java
MBaaS Features
MBaaS can save you significant development and administrative resources in your mobile app initiatives. • Data storage with Web API's • Push Notifications • Auto-Scalability - grows with demand • Client device analytics and usage statistics • Handles Identity Management and Social Authentication EX: Microsoft Azure Mobile Services • Google Firebase • AWS Mobile • Apple Cloudkit • Kinvey
What are the three methods of developing mobile apps?
Native(Write the app in the native language of the mobile operating system), Hybrid(Write the app in an intermediate language which then either compiles to native), progressive web app(Write the app in HTML and JavasScript as you would a website.)
Which method performs the best? Which is easiest to maintain and why?
Progressive Web apps because is going to work in a browser and produce something that you can put In a store.
Email - a IT manager's personal nightmare?
Technology Issues • Uses a lot of storage. • Complicated service • Requires a lot of servers to operate at scale • Illegitimate email - SPAM • Not very secure • Easy to "spoof" Policy Issues • ECPA compliance- email requires consent, being employed is consent • Archival policy • Subpoenas - pulling emails from backups for a court order • Employees use company property
RESTful API's
When a web API embraces the HTTP semantics, it is considered a RESTful API.
Progressive Web App
Write the app in HTML and JavasScript as you would a website. The look like native apps but run in a web browser.
Hybrid
Write the app in an intermediate language which then either compiles to native. Xamarian, Unity Gaming Engine, Titanium Mobile
Native
Write the app in the native language of the mobile operating system
HTTP Response Status Codes
• 1xx - Informational • 2xx - Success • 200-OK • 201 - Created • 202 - Accepted • 4xx - Client error • 400 - Bad Request • 401 - Unauthorized • 403 - Forbidden • 404 - Not Found • 5xx - Server Error • 301 - Moved Permanently • 500 - Internal Server • 3xx - Redirection • 304 - Not Modified Error • 307 - Redirect • 501 - Not Implemented • 502 - Bad Gateway
A Web API
• A Web API is an API which is executed over the HTTP or HTTPS protocols.
What is an API?
• API Stands for Application Programming Interface • It is a means to execute code other people wrote in our own programs.
Web Servers
• Apache - Open source web server. Most Popular. • IIS - Microsoft's web server • NGINX - Engine X Open source webserver, commonly used for: • Load balancing • Reverse proxies
How the web works
• Clients make requests to web servers, typically using a browser. • The client provides a request method and a URL • The web server send a response to the client. In the response is the content based on the URL • The client renders (draws) the content in the web browser
Types of IoT
• Consumer • Smart thermostats like Nest • Commercial • Pro Sports teams use data collection techniques to monitor the health of its players. • Industrial • Amazon uses robots to locate items on shelves • Infrastructure • Smart Cities
HTTP
• HTTP, or the Hypertext Transport Protocol is the data transfer protocol of the web. • It consists of requests, which contain a verb and URL and a response, which contains a status code and content type. • HTTP is a stateless protocol, which means the current request knows nothing of the previous requests. • The well-known port for HTTP is TCP/80
Components
• MUA - Mail user agent. This is usually a client like Outlook, Thunderbird, or a web browser (in the case of gmail, for instance) • MTA - Message transfer agent. Sends mail around the internet, from domain to domain. (Eg. Sendmail, exim, exchange, postfix,) • MDA - Mail Delivery agent. Writes mail to the mail message from the MDA to the message store. (Eg. procmail, exchange) • AA - Access agent. Exposes a protocol so users can read mail from the message store. Access protocols are POP3 and IMAP4 (Eg. ews, imaps, mapi)
MQTT
• Message Queuing Telemetry Transport a protocol for IoT • Messages are categorized by topics.
How is mobile different from web?
• Phones have a browser, but most of our experiences use native apps downloaded from application stores. • Native offers advantages: • Push Notifications • Offline data • Access to hardware features, camera, microphone, GPS, accelerometer • Better performance!!!
D i f f i c u l t y IoT Analytics
• Retrospective Analytics - What Happened? • Diagnostic Analytics - Why did it Happen? • Descriptive - What is happening now? • Predictive Analytics - What will happen? • Prescriptive Analytics - What should I do about it?
Hardware Defined Product
• Sensor - gathers data from environment • Actuator - alters environment (motors, etc) • Embedded System - Packages data and sends over the internet
Spam/Virus Blocking
• Spam and Viruses are normal occurrences in email, so a filtering service for both should exist in ALL email systems. • Filtering of Spam and Viruses should be done on a server, not at the email client. • Servers can be upgraded to handle increased load, clients are unpredictable. • If messages are filtered for spam or viruses, logging should also be implemented. • Sometimes false-positives can occur, which is why logging becomes important.
Why Web API's
• The Web is transitioning: • From direct user-based consumption of data • To indirect user-based consumption of data through devices and also direct device-to-device consumption.
What is IoT?
• The internet of thing is the extension of the internet into everyday things. • There is nothing revolutionary about the technologies used by IoT • IoT is a business disruptor as it has the opportunity redefine how we do business.
Developing Mobile Apps
• There are a variety of methods one can choose to make a mobile app. • Native - Write the app in the native language of the mobile operating system • Hybrid - Write the app in an intermediate language which then either compiles to native or • Progressive Web App - Write the app in HTML and JavasScript as you would a website.
Web Terminology
• URL - Uniform Resource Locator. A global name space which identifies a resource on the web. • HTML - Hypertext Markup Language. A Markup language for rendering web pages. • Web Server - A computer on the web which hosts resources. • Web Browser - A computer on the web which consumes resources • Resource - content at a URL, hosted on a web server and requested by a web browser.
