Flashcards
Untitled
Cards in this deck (39)
- 1What is Web Information System?information system that uses Internet web technologies to deliver
information and services, to users or other information
systems/applications. - 2Different Types of WISInformational
• Transactional - 3TCP:Transmission Control Protocol
a reliable connection-oriented transport service that provides end-to-end reliability, resequencing,
and flow control. - 4IP:Internet Protocol.
- 5HTTP:HyperText Transfer Protocol
- 6• FTP:File Transfer Protocol
- 7SMTPSimple Mail Transport Protocol
- 8What is the usage of HTTPHTTP is the protocol used to transfer Web pages through the Internet, at
application layer - 9layersApplication
http
• Support network applications
Transport
tcp
Provides end-to-end communication services for applications.
Internet/Network
ip4
Data Link/Physical
mac - 10UDP(User Datagram Protocol
• a connectionless ("datagram") transport service - 11What is cookie?1. Created by the server
2. Stored on user’s computer
3. Used to identify a user
4. Sent through with a page request - 12How to create a cookiesetcookie(“admin", “Helen");
- 13How to retrieve a cookieecho $_COOKIE["user"];
- 14Cookie (4/8) • Parametersexpire: when the cookie expires
• Path: the server path of the cookie
• domain: the domain name of the cookie. eg for all .uq.edu.au
secure: where or not it needs https - 15PHP - Sessions• way to store vatriable for multiple pages
user spercific
stored server side - 16• The differences between cookies and sessionscookies are stored client side
cookies live for as long as told or deleted.
sessions are server side
die when browser is closed.
sessions are liek tokens genertated at authenication
sessions are more popular, as cookies can be blocked - 17• How to start a session/store a session variable/free a session variable/destroy a sessionsession_start();
$_SESSION["favcolor"] = "green";
unset($_SESSION["favcolor"]);
session_destroy(); - 18How to implement login/logoutwrtie it out
- 19File Uploadwrite it out
- 20• Restrictions on Uploadwrite it out
- 21What is XML?eXtensible Markup Language
- 22Main difference between XML and HTMLHTML is about displaying information, while XML is about describing
information.
• HTML was designed to display data
• focus on how data looks.
• XML was designed to transport and store data
• focus on what data is - 23XML DTD• DTD is Document Type Definitions
A DTD provides a means for defining what XML mark-ups can occur in
an XML document - 24XML DTD Occurrence constraints:Occurrence constraints:
• *: 0 to many
• +: 1 to many
• ?: 0 or 1
• |: either/or - 25XML DTD which charatures interpret• #PCDATA (parsable character data):
will interpret
#CDATA (character data):
wont - 26JSON is like XML because:• They are both 'self-describing' meaning that values are named, and thus
'human readable'
• Both are hierarchical. (i.e. You can have values within values.)
• Both can be parsed and used by lots of programming languages
• Both can be passed around using AJAX (i.e. XMLHttpRequest) - 27JSON Object Creation in JSvar obj = JSON.parse(txt);
- 28• Difference between JSON object and JSON stringJSON is only the 'Notation' of a JavaScript Object, it is not actually the JavaScript 'object-literal' itself
- 29What is AJAX?• AJAX stands for Asynchronous JavaScript And XML
• AJAX is NOT a technology, but is a combination of existing
technologies and a way of thinking
• AJAX is the art of exchanging data with a server without refreshing - 30How AJAX works?1. An event occurs in a Web page (the page is loaded, a button is
clicked)
2. An XMLHttpRequest object is created by JavaScript
3. The XMLHttpRequest object sends a request to a web server
4. The server processes the request
5. The server sends a response back to the web page
6. The response is read by JavaScript
7. Proper action (like page update) is performed by JavaScript - 31database connectionwrite it out
- 32insert recordwrite it out
- 33retrieve recordwrite it out
- 34Web Security Attacks0 DOS (Deny of Service) attacks
0 SQL Injection
It is a code injection technique, used to attack data-driven
applications, in which malicious SQL statements are inserted into an
entry field for execution.
0 Cookie
0 Eavesdropping
0 Spyware - 35Security Requirements0 Confidentiality
0 Makes sure that a message is kept secret
0 Integrity
Make sure that if the content of the message is altered,
the receiver can detect it
by Digital signature
0 Authentication
Verify the identity
by Digital certification
0 Non-Repudiation
Originator of communication cannot deny it later
by Ensure Integrity and Authentication are enforced - 36Symmetric Encryption Algorithm (DES, AES, cast)Encryption and Decryption are the same
Private Key algorithm
Caesar Cypher - 37Asymmetric (RSA, DSA, ECC)Encrypt and Decrypt Keys are different
Highly secure, performance issues
Public Key System - 38how to stop sql injection1 Employ comprehensive data sanitization
2 Use a web application firewall.
3 Limit database privileges by context
4 Avoid constructing SQL queries with user input
5 Eliminate unnecessary database capabilities
6 Regularly apply software patches
7 Suppress error messages. - 393 weakness of ajaxweb indexing
browser compatabilty
reliance on js
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- Description
- Flashcards on Untitled, created by luke daniels on 19/06/2017.
- Created by
- luke daniels
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