SPAMS & ANTI SPAMSSPAMS & ANTI SPAMS

A PRESENTATION BY A PRESENTATION BY

SUDIPTA BHATTACHARYASUDIPTA BHATTACHARYA

B-TECH(III) EXAMINATION,2008B-TECH(III) EXAMINATION,2008

ROLL-91/CSE/ NO-060022ROLL-91/CSE/ NO-060022

AGENDAAGENDA

Spam definitionSpam definition OriginOrigin ClassificationClassification CostCost How spammers earns moneyHow spammers earns money Spam sending techniquesSpam sending techniques Ill effectsIll effects Antispam techniquesAntispam techniques ConclusionConclusion

SPAMDEFINITION & ORIGINSPAMDEFINITION & ORIGIN Definition:Definition: Spam also called junk email or bulk email can be Spam also called junk email or bulk email can be

defined as unsolicited e-mail, often of a commercial defined as unsolicited e-mail, often of a commercial nature, sent indiscriminately to multiple mailing lists, nature, sent indiscriminately to multiple mailing lists, individuals, or newsgroups. The intention is to individuals, or newsgroups. The intention is to frustrate the receiver and also to income money.frustrate the receiver and also to income money.

Origin:Origin: Due to the international nature of spam, the spammer, Due to the international nature of spam, the spammer,

the hijacked spam-sending computer, the the hijacked spam-sending computer, the spamvertised server, and the user target of the spam spamvertised server, and the user target of the spam are all often located in different countries.are all often located in different countries.

CLASSIFICATION(W.R.T MEDIA)CLASSIFICATION(W.R.T MEDIA)

Spamming Spamming is the abuse of electronic is the abuse of electronic messaging systems to indiscriminately send messaging systems to indiscriminately send unsolicited bulk messages. While the most unsolicited bulk messages. While the most widely recognized form of spam is e-mail widely recognized form of spam is e-mail spam, the term is applied to similar abuses in spam, the term is applied to similar abuses in other media: other media:

(1)Usenet newwsgroup spam(1)Usenet newwsgroup spam (2)Chat spams(2)Chat spams (3)Search engine spam e.t.c(3)Search engine spam e.t.c

CLASSIFICATION CLASSIFICATION E-MAIL SPAM:E-MAIL SPAM: E-mail spam, also known as E-mail spam, also known as unsolicited bulk email unsolicited bulk email

(UBE)(UBE) or or unsolicited commercial email (UCE),unsolicited commercial email (UCE), is the is the practice of sending unwanted e-mail messages, practice of sending unwanted e-mail messages, frequently with commercial content, in large frequently with commercial content, in large quantities to an indiscriminate set of recipients.Email quantities to an indiscriminate set of recipients.Email spam targets individual users with direct mail spam targets individual users with direct mail messages. Email spam lists are often created by messages. Email spam lists are often created by scanning scanning Usenet postingsUsenet postings,, stealing stealing Internet mailing Internet mailing lists,lists, or searching the or searching the Web for addresses.Web for addresses.

CLASSIFICATIONCLASSIFICATION

USENET NEWSGROUP SPAM:USENET NEWSGROUP SPAM:

UsenetUsenet (a contraction of user network), is a world- (a contraction of user network), is a world-wide distributed Internet discussion system. It was wide distributed Internet discussion system. It was conceived by Duke University graduate students Tom conceived by Duke University graduate students Tom Truscott and Ji Ellis in 1979. Users read and post Truscott and Ji Ellis in 1979. Users read and post public messages (called articles or posts, and public messages (called articles or posts, and collectively termed news) to one or more categories, collectively termed news) to one or more categories, known as known as newsgroupnewsgroup. Newsgroup spam is a type of . Newsgroup spam is a type of spam where the targets are Usenet newsgroups.spam where the targets are Usenet newsgroups.

CLASSIFICATIONCLASSIFICATION CHAT SPAMS:CHAT SPAMS: can occur in any live chat environment like IRC and can occur in any live chat environment like IRC and

in-game multiplayer chat of online games, and in any in-game multiplayer chat of online games, and in any other form of chat the masses are able to view. It other form of chat the masses are able to view. It consists of repeating the same word or sentence many consists of repeating the same word or sentence many times to get attention or to interfere with normal times to get attention or to interfere with normal operationsoperations

WEB SEARCH ENGINE SPAM:WEB SEARCH ENGINE SPAM: SpamdexingSpamdexing ( ( spammingspamming and and indexingindexing) refers to the ) refers to the

practice on the World Wide Web of modifying practice on the World Wide Web of modifying HTML pages to increase the chances of them being HTML pages to increase the chances of them being placed high on search engine relevancy lists. placed high on search engine relevancy lists.

OTHER SPAMSOTHER SPAMS Image spamImage spam Image spam is an obfuscating method in which the text Image spam is an obfuscating method in which the text

of the message is stored as a GIF or JPEG image and of the message is stored as a GIF or JPEG image and displayed in the email. Often, image spam contains displayed in the email. Often, image spam contains nonsensical, computer-generated text which simply nonsensical, computer-generated text which simply annoys the reader.annoys the reader.

Blank spamBlank spam Blank spam is spam lacking a payload advertisement. Blank spam is spam lacking a payload advertisement.

Often the message body is missing altogether, as well Often the message body is missing altogether, as well as the subject line. Still, it fits the definition of spam as the subject line. Still, it fits the definition of spam because of its nature as bulk and unsolicited because of its nature as bulk and unsolicited email.Blank spam may be originated in different ways, email.Blank spam may be originated in different ways, either intentional or unintentionally:either intentional or unintentionally:

COST OF SPAMCOST OF SPAM Spam is the curse of the Internet. Spam is the curse of the Internet.

It clogs inboxesIt clogs inboxes Crashes servers Crashes servers

Wastes time and money Wastes time and money

Loss of productivity and is an abuse of privacy.Loss of productivity and is an abuse of privacy.

HOW SPAMMERS EARNS HOW SPAMMERS EARNS MONEY:MONEY:

Some spammers have a business model that lets them Some spammers have a business model that lets them make money as long as people simply visit their make money as long as people simply visit their website. We don't need to sign up for a spammer's website. We don't need to sign up for a spammer's online site, for example, because just visiting their online site, for example, because just visiting their publicly available website will be enough to ensure publicly available website will be enough to ensure that the spammer gets advertising revenue from that the spammer gets advertising revenue from banner ads displayed on those pages. banner ads displayed on those pages.

HOW SPAMMERS SEND SPAMSHOW SPAMMERS SEND SPAMS

Gathering of Email addressGathering of Email address this is called email address harvesting .A large set of email this is called email address harvesting .A large set of email

addresses are collected without the consent of the address addresses are collected without the consent of the address owner.owner.

Delivering spam messagesDelivering spam messages this can be done using the following alternativesthis can be done using the following alternatives (1)Using web mail services(1)Using web mail services (2)Using other peoples computer(2)Using other peoples computer (3)Open relays(3)Open relays (4)Open proxies(4)Open proxies

ILL EFFECTS OF SPAMILL EFFECTS OF SPAM The ocean of spam problemThe ocean of spam problem

Spams are growing larger in size. Our mailbox will not Spams are growing larger in size. Our mailbox will not be able to accommodate real mailsbe able to accommodate real mails

Deception and fraudDeception and fraud

Spammers often use false names, addresses, phone Spammers often use false names, addresses, phone numbers, and other contact information to set up numbers, and other contact information to set up "disposable" accounts at various Internet service providers. "disposable" accounts at various Internet service providers.

Theft of serviceTheft of service

SMTP often being compromised by spammers.SMTP often being compromised by spammers. It might be illegalIt might be illegal

ANTISPAM TECHNIQUESANTISPAM TECHNIQUES

Actions by individualActions by individual

Automated by email administratorAutomated by email administrator

Automated by sendersAutomated by senders

Employed by researches and law enforcementEmployed by researches and law enforcement

ACTIONS BY INDIVIDUAL:ACTIONS BY INDIVIDUAL:

Detecting spamDetecting spam Detecting spam based on the content of the e-mail, either Detecting spam based on the content of the e-mail, either

by detecting keywords such or by statistical means, is by detecting keywords such or by statistical means, is very popularvery popular

End user techniquesEnd user techniques There are a number of techniques that individuals can use There are a number of techniques that individuals can use

to restrict the availability of their e-mail addresses, to restrict the availability of their e-mail addresses, reducing or preventing their attractiveness to spam.reducing or preventing their attractiveness to spam.

(1)Address munging(1)Address munging (2)Avoid responding to spam(2)Avoid responding to spam (3)Disabling HTML in email(3)Disabling HTML in email (4)Spamming the spammers etc.(4)Spamming the spammers etc.

AUTOMATED BY EMAILAUTOMATED BY EMAIL

ADMINISTRATORSADMINISTRATORS

There are a number of appliances, services and There are a number of appliances, services and software systems that e-mail administrators can use to software systems that e-mail administrators can use to reduce the load of spam on their systems and reduce the load of spam on their systems and mailboxes.mailboxes.

Some of these depend upon rejecting email from Some of these depend upon rejecting email from Internet sites known or likely to send spam. This Internet sites known or likely to send spam. This technique is called technique is called BLOCKING.BLOCKING.

Others rely on automatically analyzing the content of Others rely on automatically analyzing the content of email messages and weeding out those which email messages and weeding out those which resemble spam. This is called resemble spam. This is called FILTERING.FILTERING.

AUTOMATED TECHNIQUES BY AUTOMATED TECHNIQUES BY EMAIL ADMINISTRATORSEMAIL ADMINISTRATORS

Authentication and reputation.Authentication and reputation. Challenge response systems.Challenge response systems. Checksum based filteringChecksum based filtering Country based filtering.Country based filtering. Hybrid filtering.Hybrid filtering. Rule based filtering.Rule based filtering. Statistical filtering.Statistical filtering. Enforcing RFC standard.Enforcing RFC standard.

AUTOMATED BY EMAIL AUTOMATED BY EMAIL SENDORSSENDORS

There are a variety of techniques that e-mail senders use to try There are a variety of techniques that e-mail senders use to try to make sure that they do not send spam.to make sure that they do not send spam.

TechniquesTechniques:: Background check on new customer or userBackground check on new customer or user Since spammers are frequently kicked off the network, they Since spammers are frequently kicked off the network, they

are constantly trying to create new accounts. As a result, are constantly trying to create new accounts. As a result, manISPs and web –email providers try to verify the credit manISPs and web –email providers try to verify the credit cards are not stolen before accepting new customerscards are not stolen before accepting new customers

Confirmed opt in for mailing list:Confirmed opt in for mailing list: If a user wants to be a subscriber of a product in the mailing If a user wants to be a subscriber of a product in the mailing

list then the latter (the mailing s/w) sends a confirmation list then the latter (the mailing s/w) sends a confirmation message to the user and after getting the response adds the message to the user and after getting the response adds the user mail address to the list.user mail address to the list.

NEW RESEARCH & LAW NEW RESEARCH & LAW ENFORCEMENTENFORCEMENT

Ham password:Ham password: Association of email and password together with the Association of email and password together with the

filtering mechanism provides a better technique to filtering mechanism provides a better technique to protect against spams.protect against spams.

Cost based systems:Cost based systems: Sender should pay some cost in order to send Email.Sender should pay some cost in order to send Email. Proof of the work:Proof of the work: Proof-of-work systems such as hashcash require that Proof-of-work systems such as hashcash require that

a sender pay a computational cost by performing a a sender pay a computational cost by performing a calculation that the receiver can later verify. calculation that the receiver can later verify.

OTHER TECHNIQUESOTHER TECHNIQUES

There are a number of proposals for sideband There are a number of proposals for sideband protocols that will assist SMTP operation.The protocols that will assist SMTP operation.The Anti-Spam Research Group (ASRG)Anti-Spam Research Group (ASRG) of the of the Internet Research Task Force(IRTF)Internet Research Task Force(IRTF) isworking isworking on a number of E-mail authentication andother on a number of E-mail authentication andother proposals for providing simple source proposals for providing simple source authentication that is flexible, lightweight, and authentication that is flexible, lightweight, and scalable.scalable.

CONCLUTIONCONCLUTION

To prevent e-mail spam, both end users and To prevent e-mail spam, both end users and administrators of e-mail systems use various administrators of e-mail systems use various

anti-spam techniques. Some of these techniquesanti-spam techniques. Some of these techniques have been embedded in products, services and have been embedded in products, services and

software to ease the burden on users and software to ease the burden on users and administrators. No one technique is a complete administrators. No one technique is a complete solution to the spam problem, and each has trade-solution to the spam problem, and each has trade-

-offs between incorrectly rejecting legitimate e-mail -offs between incorrectly rejecting legitimate e-mail vs. not rejecting all spam, and the associated costs vs. not rejecting all spam, and the associated costs

in time and effort.in time and effort.

REFERENCESREFERENCES

(1)E-mail spam - Wikipedia, the free (1)E-mail spam - Wikipedia, the free encyclopediaencyclopedia

(2)Anti-spam techniques (e-mail) - Wikipedia, (2)Anti-spam techniques (e-mail) - Wikipedia, the free encyclopediathe free encyclopedia

(3)Spam (electronic) from wikipedia(for (3)Spam (electronic) from wikipedia(for classification)classification)

(4)Economics of spam-(4)Economics of spam-Joe St Sauver, Ph.D.Joe St Sauver, Ph.D. Director, User Services and Network Director, User Services and Network ApplicationsApplications joe@uoregon.edujoe@uoregon.edu..

THANKYOUTHANKYOU