a detailed ppt on web-mail filter.

2. Introduction
In today’s world electronic mail (or
popularly known as e-mail) is a very
powerful medium for transferring messages
to other users.
Like every powerful medium it is prone to
be misused.
One such case of misuse is the posting of
unsolicited emails known as spam.

3.  Too noisy Inbox.
Misleading information
distribution.
 Virus spreading programs
and Mails
Wastage of allocated
memory space for Inbox.

5. Spam filtering comes in two
forms
Server side filtering
Client side filtering
The filtering occurs on the server
before the emails are seen.
User filters that are created by
the email client, redirects emails
that are 'marked as Spam’ to a
specific 'Spam' folder

6.  Recognizing the words that are likely to appear as spam.
 universal virus definitions.
 universal block list of IP addresses(UBL).
Client side filtering
 Checking the mails against Subject and from Email ID specified
by the user.
 Checking the mails against the size limit of the mail specified by
the User.
Reporting a message as “spam” by the user.


7. Architecture

8. Admin: This module deals with the management of the application by a
person called Administrator who is responsible for taking all the mails coming to
the people working in the organization, and invoking the filtering mechanism
can also specify UBL IP addresses and Universal Virus definitions in order to
protect the systems from attack.
User:
This module deals with user processing. In this module user can
specify what he doesn’t want.
Filtering:
This module deals with the major task of Mail Filter

9. Spam filtering mechanism in gmail
How messages are marked as Spam in
Gmail???
Gmail has an automated system that helps detect
spam by identifying viruses and suspicious
messages and learning
from what Gmail users like
us commonly
mark as spam.

10. why that a particular message in
GMAIL is placed in Spam?
Phishing scams
Messages from an unconfirmed sender.
Message content is empty
Messages you sent to Spam
Administrator-set policies

11. Messages from an
unconfirmed sender
Spammers can forge a message to make it
look like it's sent by a real website or
company that you might trust. To help
protect you from such messages, Google
tries to verify the real sender using email
authentication

12.  Messages you sent to Spam
You previously marked these messages as spam by clicking
the "Report spam" or "Report phishing" button
 Administrator-set policies
If your organization uses Gmail, the administrator within
your group can decide what messages will be marked as spam.

13. Increased productivity
Personalized filter.
Phishing scam protection
White listing capabilities.
Users who receive a low volume of email will have to wait
longer to establish an adequate database.
Word based filters and list based filters have lots of
disadvantages
Disadvantages

14.  Email filter is used to inspect outgoing email at some
companies to ensure that employees comply with
appropriate laws.
 Malware can comprise a user's sensitive private data
by capturing bank account information, usernames
and passwords. Spam blocker applications can assist a
user in preventing these types of PC contaminations.

15. Web mail filter is a mechanism for classifying
message as either spam or non-spam.
Its reduces the overhead for the users by filtering
out unwanted or uninvited messages in the inbox.
It provides security for your mailbox by filtering
out contaminated messages.
Based on the future security issues, security can be
improved using emerging technologies.

16.  A survey on spam
filtering:www.scirp.org/journal/PaperInformation.aspx
 en.wikipedia.org/wiki/Anti-spam_techniques
 Defeating spam:www.techtarget.com
 Email Spam Filtering:Gordon V. Cormack
 www.howstuffworks.com
 www.ieee.org/documents/ieeecitationref.pdf