An Introduction

1. Context &
Relevant Issue
Subject:
Web Engineering
Presented by :
Umer Farooq
Bs-IT- (3049)
Evening -5th
University of Education okara ,Renala
Campus1

2. Cookies Sessions
Limited storage space Practically unlimited
space
Insecure storage client-
side
Reasonably securely
stored server-side
User controlled No user control

3. Cookies and Sessions
 Cookies are useful for storing user info that
should be retained from one page to the
next. (Overcome the ‘stateless’ nature of
the web)
 Cookies are written to the client’s hard
drive.

4. Issues
 User can disable cookies in the browser
 Cookies may be viewed by other users
 Can only store 20 cookies; max 4KB.
 Some browsers may display incorrectly
unless all options are set in setcookie()
(e.g expiration time, path)
C:documents and
settingsjceddiacookiesjceddia@phpbuilder[1].txt

5. Cookies
 Shortcomings of using cookies to keep data
 User may turn off cookies support.
 Data are kept with the browser
 Users using the same browser share the cookies.
 Limited number of cookies (20) per server/domain and
limited size (4k bytes) per cookie
 Client can temper with cookies
 Modify cookie files, use JavaScript to create/modify cookies,
etc.

6. Notes
 Don't always rely on cookies as the client
may have turned off cookies support.
 Don't store sensitive info in cookies

7. Notes
 Don't always rely on cookies as the client
may have turned off cookies support.
 Don't store sensitive info in cookies