Annotated Bibliography

Annotated Bibliography

‘ HUAIQING WANG, MATTHEW K.P. LEE. AND CHEN WANG *

Consumer

PRIVACY CONCERNS

about Internet Marketing

The Internet is quickly becoming the world’s

largest public electronic marketplace. It is

>^BUYER’S-EYE VIEW OF estimated to reach

ONLINE PURCHASING 50 mil l ion people

WORRIES, f—–^’ \ woridwide, with

growth estimates averaging approximately

10% per month. Innovative business profes-

sionals have discovered that the Internet can

COMMUNICATIONS OF THE ACM March 1998/Vol. 41. No. 3 63

A major impediment against full-scale integration

of the Internet marketplace with modern business is

the lack of confidence Internet consumers have in the

newly developed marketing machinery.

be exploited to offer a number of services both for their customers and for their strategic partners. The Internet has also revolutionized retail and direct marketing. Consumers are able to shop from their homes for a wide variety of products from manufac- turers and retailers all over the world. They are able to view these products on their computers or televi- sions, access information about the products, visual- ize the way the products may fit together, and then order and pay for their choices. The Internet has changed modern business and presented a new para- digm of business relationships and transactions.

Despite the much-heralded recent successes in uti- lizing the Internet marketplace, one of the major impediments against full-scale integration of the Internet marketplace with modern business is the lack of confidence Internet consumers have in the newly developed marketing machinery [l, 2]. The most cru- cial issue that Internet consumers have identified is fear and distrust regarding loss of personal privacy associated with the emerging electronic commerce marketplace. One recent. survey undertaken by Equifax and Harrjs Associates determined that over two-thirds of Internet consume’rs considered the pri- vacy concern to be very important [3, 7].

Despite its importance, the available literature on Internet marketing and privacy is often ad hoc, sketchy, and at times contradictory. There is a clear need for systematic research to synthesize ideas from various sources in order to arrive at a comprehensive picture of the relevant issues. This article presents such a comprehensive picture from the consumer’s privacy perspective. For companies engaging in Inter- net marketing, this article enables them to become better aware of consumer privacy issues and better equipped for the implementation of privacy codes for fair information practices. For consumers, this article provides a comprehensive picture of the issues involved and knowledge of the relevant privacy enhancing technologies and tools that they can use to protect themselves.

What is Consumer Privacy? The term privacy is usually described as “the right to be let alone,” and is related to solitude, secrecy, and

autonomy. However, when associated with consumer activities that take place in the arena of the elec- tronic marketplace, privacy usually refers to personal information and the invasion of privacy is usually interpreted as the unauthorized collection, disclo- sure, or other use of personal information as a direct result of electronic commerce transactions. When it comes to the invasion of personal information pri- Vacy, the types of personal information that are involved can be classified into two major categories based on their nature.

On the one hand, personal information that is not expected to change dramatically over time can be referred to as static private information, such as referen- tial information, historical financial information, health information, personal affiliations and beliefs, and personal documents.

Other private information includes information that changes dramatically over time, but nevertheless can be collected and analyzed in such a way that a well-informed individual profile may be generated. This information is referred to as dynamic personal information, such as activity history and activity content.

A Taxonomy for Privacy Concerns There exists a wide range of Internet marketing activities that have negative effects on the Internet consumer’s individual privacy [5, 9]. The privacy concerns are not limited to the more well-known cases of junk mailing [6, 8], or illicit Web cookie distribution, but have expanded to certain practices that have become cornerstones of Internet mer- chants’ revenue streams, for example, the selling of consumer databases for direct marketing purposes. Over the past few years, we have seen evidence of an increasing number of privacy-related cases, as related to the growth of Internet marketing activities:

• Privacy concerns related to the activities of junk email marketing organizations, such as CyberPro- motions and net.net.

• The activities of Web-based advertisements that track the user’s usage history and preferences through cookies, such as those from Dou- bleClick.net, Preferences.com, and many others.

6 4 March 1998/Vol. 41. No. 3 COMMUNICATIONS OFTHE ACM

‘ Privacy concerns over malicious programs that can be constructed through security holes in many Internet tools, such as Java, ActiveX, JavaScript, and many others. Well-known malicious tech- niques include ActiveX controls that can obtain a person’s credit information and JavaScript that accesses personal files.

‘ Privacy concerns regarding the use and transfer of private information, illustrated by the cases involving; MSN (Microsoft Network) and their practice of tracking all activities of their sub- scribers; Microsoft Side Walk viewers and their viewing activity patterns to be used for Microsoft marketing purposes. Choices to opt out of such practices are often non-existent or extremely diffi- cult to exercise.

vacy infringement results in the exposure of private information to unauthorized viewers, often resulting in the collection of such information for marketing purposes.

Improper Collection: To collect a consumer’s pri- vate information from the Internet without notice to or acknowledgment from the consumer. Such private information includes a consumer’s email address, types of software the consumer uses, the consumer’s Web access history, private files or databases, etc. Usually, improper collection will lead to improper analysis and improper transfer.

Improper Monitoring: To monitor (conduct sur- veillance on) a consumer’s Internet activities without notice to or acknowledgment from the consumer. By using cookies, Internet marketing businesses are able

1

Direct < mailing

Preference tracking

Unwanted eavesdrop

No opting-out

Third-party distribution

Improper acquisition

Improper access

E

P

Improper collection

E

E

Improper monitoring

E

E

Improper use

Improper analysis

P

E

E

Improper transfer

E

Privacy invasion

Unwanted solicitation

E

Improper storage

P

P

Table I. A

taxononny

of privacy

concerns

£• Explicit P: Probable

• Concerns over distribution, often for financial gains, of private information, often for purposes other than the purpose for which it was collected: a noted case is the recent example of America Online selling its subscriber contact information, financial information, and Internet activities.

Table 1 shows a taxonomy of consumer privacy con- cerns in the Internet marketing area. This table also describes the relationships between the Internet mar- keting actiyities (rows) and the privacy concerns (columns). For instance, the first row shows that direct niailing usually causes unwanted solicitation and probably causes improper use of private information.

The column headings appearing in Table 1 are defined in greater detail as follows:

Improper Access: To infiltrate an Internet con- sumer’s private computer without notice to or acknowledgment from the consumer. This type of pri-

to watch where and when the consumer visits Web sites, how long the consumer stays, and what type of transactions the consumer conducts. In most cases, improper monitoring will result in improper analysis.

Improper Analysis: To analyze a consumer’s pri- vate information without proper notice, and to derive conclusions from such an analysis. Such conclusions may include a consumer’s shopping and spending patterns, shopping behaviors and preferences. The collection of private information by an Internet mer- chant initially for one particular purpose, but its sub- sequent use for other purposes without consent from the consumer, not only could be described as improper analysis but also could result in improper transfer.

Improper Transfer: To transfer a consumer’s pri- vate information to other businesses without notice to or acknowledgment from the consumer. For instance, various Internet companies sell, publish, distribute, and share their customer databases, which contain cus-

COMMUNICAT1ONS OF THE ACM March 1998/Vol. 41. No. 3 65

The balancing of beneficial uses of data sources with

the privacy rights of individuals is truly one of the most

challenging public policy issues of the information age.

tomer private information such as postal and email addresses.

Unwanted Solicitation: To transmit information to potential Internet consumers without their acknowledgment or permission. Such privacy inva- sions include junk mail, mass direct email, and junk Internet push channels.

Improper Storage: To keep private information in a non-secure manner resulting in a lack of trustwor- thiness of the stored information, or lack of authenti- cation control for information access. For instance, enabling individual account holders to view private information concerning other accounts, changing information without proper authorization would con- stitute such privacy concerns. Improper storage is commonly related to the concerns of information con- fidentiality and data integrity.

Principles for Protecting Privacy The key issue of privacy in the Internet marketplace is that the privacy rights of individuals should be balanced with the benefits associated with the free flow of information. Protecting privacy must be undertaken in combination with a number of other efforts. There are three main parties involved, each playing different roles:

• Government: promoting strong privacy laws for both the public and private sectors; establishing independent privacy commissions to oversee the implementation of these laws; educating the public about privacy issues; encouraging business self-regulation.

• Businesses: promoting self-regulation for fair information practices.

• Individuals: adopting privacy enhancing technologies, such as network and information security tools.

The U.S. government has recently recommended a set of principles (the “Privacy Principles”) governing the collection, processing, storage, and reuse of per- sonal data:

I. General Principles: To guide all the partici- pants and identify the fundamental requirements

necessary for the proper use of personal information, and in turn the successful implementation of pri- vacy. Personal information should be acquired, dis- closed, and used only in ways that respect an individual’s privacy. Such information should not be improperly altered or destroyed and should be accu- rate, timely, complete, and relevant for the purpose for which it is provided and used.

II. Principles for Users of Personal Informa- tion: Businesses should assess the impact on privacy in deciding whether to acquire, disclose, or use per- sonal information, and use appropriate technical and managerial controls to protect the confidentiality and integrity of personal information. Businesses should not use personal information in ways that are incom- patible with the individual’s understanding of how it will be used, and should educate themselves and the public about how information privacy can be main- tained.

III. Principles for Individuals Who Provide Personal Information: Individuals should obtain adequate, relevant information about why informa- tion is collected, what it is to be used for, how to pro- tect it, how to provide and withhold it and rights of redress, and they should be able to safeguard their own privacy by having a means to obtain information, a means to correct errors, a means of redress if harmed by an improper disclosure or use of personal informa- tion, and the ability to use appropriate technical con- trols to protect personal information, and to remain anonymous.

Regulatory Protection for Privacy Privacy is a complex concept. An acceptable use of private information in one setting may be an unac- ceptable invasion of privacy in another. In this sec- tion, only those regulations related to consumer privacy in Internet marketing are discussed. A large number of governments have introduced privacy protection laws. In the U.S., the Privacy Act was passed in 1974. This Act restricts the collection, use, and dissemination of personal information by federal agencies. This Act generally applies only to federal records, but not to foreign visitors, private corpora- tions, or other organizations. In 1988, the Computer Matching and Privacy Act was introduced, regulat-

66 March 1998/Vol. 41. No. 3 COMMUNICATIONS OFTHE ACM

ing federal a!gencies’ use and exchange of information contained in existing agency databases. The U.S. government has also introduced a number of laws to protect all real-time communications and stored transmissions. For instance, the Telecommunications Act of 1996 imposes limits on the use of customer proprietary network information by common carri- ers. In Europe, the Council of Europe passed Con- vention 108 (Convention for the Protection of Individuals with Regards to Automatic Processing of Personal Data) in 1981. It protects personal data held by both the private and public sectors. It also protects individual freedom by placing limits on the collection, storage, and transmission of personal information. In Asia, for example. Hong Kong has

nesses in the Internet markets are paying more atten- tion to the need for consumer privacy. A growing number of voluntary businesses, from banking and insurance to direct Internet marketing and telecom- munications, have written their own privacy codes in an effort to fend off legislation and nurture a much- needed degree of confidence among their consumers.

Privacy Enhancing Technologies While regulatory approaches aimed at addressing privacy issues in Internet marketing have received considerable attention, the successful integration and widespread acceptance of privacy regulations are still not a reality. On the other hand, a self-initiated pri- vate industry aimed at providing technological solu-

Table 2. Relationships

between

privacy

enhancing

technologies

and privacy

concerns

Improper access

Improper collection

Improper monitoring

Improper use

Improper transfer

Unwanted solicitation

Improper storage

Awareness principle

Merchant profiling

P

P

P

P

P

Trust framework

E

P

P

P

P

P

Empowerment principle

Access control

E

User pref. profiling

P

P

P

P

P

P

Anonymity

E

P

Encryption

E

P

E

Redress principle

Content filtering

E

£• Effeaive P: Panially effective

instituted privacy legislation in relation to personal data [4], which is not dissimilar to the provisions of Convention 108.

However, many privacy issues are in the so-called “gray” area. Many industries in the private sector are now introducing meaningful, consumer-friendly, self- regulatory privacy regimes in their operations. These include mechanisms for facilitating awareness and the exercise of choice online, evaluating private sector adoption of and adherence to fair information prac- tices, and dispute resolution. The Direct Market Asso- ciation (DMA) has, for example, established a number of codes and guidelines for self-regulatory actions for its members. For instance, the Mail Preference Service (MPS) and the Telephone Preference Service (TPS) handle unsolicited junk mail and telemarketing. Busi-

tions to practical Internet marketing privacy concerns has been growing at a dramatic rate. Emerging standards as well as the myriad of prod- ucts embodying privacy enhancing technologies are providing a wealth of individualistic technological choices that one can make to enhance the protection of one’s privacy in the context of Internet commerce (see Table 2).

P3 and OPS. One of the leading efforts by the technology industry aimed at standardizing privacy preference expression has been undertaken by the World-Wide Web Consortium (W3C), a non-profit group specializing in proposing and enforcing stan- dards on the Web. The Platform for Privacy Prefer- ence (P3) standard will enable Internet consumers to be informed and to make choices about the collection.

COMMUNICATIONS OF THE ACM Marïh 1998/Vol. 41. No. 3 67

use and disclosure of their private information on the Web. Under P3 each Internet merchant will profile and register his or her own privacy practice. In an event in which an Internet consumer’s privacy prefer- ence matches with the privacy practice profile of the Internet merchant, then no action will be taken. Oth- erwise, the Internet consumer will be informed of the discrepancies, and he or she will be able to make

ported the standardization efforts such as P3 and OPS, but nevertheless is concerned with the lack of audit and enforcement processes dealing with discrepancies between the privacy profile and actual privacy prac- tices. Profiling techniques can only partially deal with the concern of lack of consumer privacy in the Inter- net marketplace.

Trust Framework. A number of firms offer tech-

Netscape Browser IE Browser Netscape Server IE Server VeriSign Nortel Entrust GTE CyberTrust TRUSTe NetNanny CyberSitter UNIX, WinNT TIS Gauntlet Remailer Anonymizer.com CyberCash Jango PGP PGP CookieCutter DiskCrypt RSA SecurePC Intermute

MP

+ + + + +

Fable 3. Internet s

T.F.

Ce

** ** ** ** ** ** **

*

*

*

Ra

+ +

** * *

oftware tools and

Ac.Con.

IP

** ** *

** *

*

* * ** *

** *

GP

**

*

* **

TP

**

*

*

UPP

+ +

+

privacy enhancing technologies

Anony.

Re

** *

*

Ag

**

Encry.

Co

**

**

*

*

St

* *

*

*

** **

CF

**

* *

*

**

**

Web URL

www.netscape.com wvi/w.microsoft.com wvvw.netscape.com www.microsoft.com www.vensign.com wvvw.centrust.com www.cybertrust.gte.com vvww.truste.org www.netnanny.com www.cybersitter.com various www.tis.com soda.csua.berkeley.edu wvvw.anonymizer.com vvww.cybercash.com www.marimba.com www. pgp.com www.pgp.com www.diskcrypt.com www.rsa.com www.intermute.com

*: support; **: strong support; +: future support

MP: Merchant Profiling UPP: User Pref. Profiling T.F.: Trust Framework Anony.: Anonymity Ce: Digital Certificate Re: Anonymous Redirection Ra: Review and Audit Ag: Anonymous Agents Ac.Con.: Access Control Encry.: Encryption IP: Individual Permit Co: Encryption for Communication GP: Group Permit St: Encryption for Storage TP: Tool Permit (e.g., switch off Java) CF: Content Filtering

choices regarding whether to accept or reject each dis- crepancy. The P3 standard is based largely on the OPS (Open Profiling Standard) submitted by Internet technology vendors: Netscape (which has already announced plans to support P3 in browser and server environments). Firefly (using a proprietary technology in which consumers can submit preference profiles), and VeriSign (which will issue the trusted identity for all the parties involved in the Internet market). Microsoft has also indicated that it intends to support the P3 standard in its future products.

The Internet consumer community has largely sup-

nological services to tackle the central issue of univer- sal trust infrastructure. Such a service provides non-repudiation of identity, practices, and privilege for both Internet consumers and Internet merchants.

The service offered by VeriSign (www.verisign. com) deals exclusively with the problem of estab- lishing a trusted identity through the accreditation of the public key, producing what is commonly known as a digital certificate. Verification of iden- tity as established by VeriSign is done through a process called Digital Signature, in which the certifi- cate is checked for VeriSign’s authentication signa-

68 March 1998/Vol. 41. No. 3 COMMUNICATIONS OF THE ACM

ture. From a privacy perspective, both the Internet consumer and Internet merchant will have to be veri- fied to be trusted in order for an electronic transaction to occur. By dealing with an Internet merchant that is considered trusted, Internet consumers will not have to be concerned about improper access to their private data. Furthermore, issues of improper information col- lection, improper monitoring and confidentiality can also be dealt with in a similar manner through trusted identities.

On other hand, the services offered by TRUSTe (www.truste.org) are aimed at providing Internet con- sumers with a trusted brand of privacy practices. TRUSTe can review and audit sites to ensure they cor- rectly disclose their information practices. This approach resembles a regulatory approach in their efforts to deal with improper collection, use, and transfer in a fashion that is limited by the extent of the universality of TRUSTe’s service.

Anonymity and Encryption. At present, the most successful atid widely used technology that has had a significant iiTipact on the privacy concerns of Internet consumers has been cryptography. Confidentiality of communication between the two communicating par- ties is dealt with, as any observing third party can not view the contents of a message. Furthermore, encryp- tion can also be utilized for the purpose of protecting one’s own data, since undesirable parties cannot collect useful information regarding the Internet consumer. Encryption privacy enhancing technology is often bundled with digital signature technology as the tech- nology undeirlying an international secure infrastruc- ture, providing effective authenticated, confidential and verifiable means of Internet commerce between Internet merchants and consumers.

Another means of protecting the Internet con- sumer’s privacy is to enable Internet consumers to carry out their activities in an anonymous manner. Numerous current efforts are aimed at enabling Inter- net consumers to carry out anonymous activities, such efforts include CyberCash (www.cybercash.com), which enables anonymous cash usage in Internet commerce; various anonymous remailers that enable anonymous email communications; Anonymiser.com, which permits consumers to browse the Web anonymously; and intelligent Web agents SLich as Jangö (www.marimba.com).

Local Control and Filtering. In terms of protect- ing one’s own privacy, a wide variety of privacy enhancing technologies have been developed, permit- ting an individual Internet consumer to choose the level and scope of personal information to be made available to Internet merchants. The first category of personal privacy enhancing technology deals with the

issue of access control, in the sense that information is given to Internet merchants only when the required permission is granted. Such a technology has been widely used in the area of controlling access of Inter- net merchant applications, such as Java, ActiveX, JavaScript, and many others. Individual Internet con- sumers can enable or disable accesses (such as file sys- tem accesses, or communicating with the Internet merchant) based on the marketing purpose of the mer- chant application. Recently, Internet merchant appli- cations have adopted the certificate and trust framework to provide the consumer with a better sense of understanding with regard to the origin of such applications, resulting in trusted Java and ActiveX technologies. Corporations have long applied various access control technologies, such as firewalls, and proxy servers, not only to protect the privacy of individual corporate users, but also to protect the con- fidentiality of the organization as a whole.

An individual Internet consumer also may decide to utilize the various privacy enhancing technologies that perform the function of filtering individual Inter- net marketing messages based on their contents. In the area of electronic message filtering, products such as Intermute and Junk Mail filter have enabled the consumer to resist direct Internet mail marketing efforts and therefore address the privacy concern of unwanted solicitation. Furthermore, parents have long been protecting the privacy of their children by using popular Internet filtering software such as Net Nanny, and Cyber Sitter, which filter out the inappropriate content that may be present (see Table 3).

Conclusion Internet marketing holds a tremendous potential for businesses and consumers, but it may also cause pri- vacy violations. The balancing of beneficial uses of these data sources with the privacy rights of individ- uals is truly one of the most challenging public pol- icy issues of the information age. Consumers in the Internet marketplace want to control what personal information is disclosed about them, to whom, and how that information will be used and further dis- tributed. In this article, we have outlined a taxon- omy that helps describe, categorize, and analyze consumer privacy concerns. We have also reviewed the current state-of-the-art technology, and pointed out the imminent integration of business self-regula- tion, regulated law enforcement, and the consumer’s ability to enhance individual privacy protection through the use of technology. However, the future is not all rosy. There remains much that needs to be done in order to make the Internet a widely accept- able marketplace for the exchange of goods and ser-

COMMUNICATIONS OF THE ACM March 1998/Vol. 41. No. 3 69

Major Privacy-related Organizations

Electronic Privacy Information Center: www.epic.org American Civil Liberties Union: www.aclu.org

Consumer Project on Technology: www.essential.org/cpt/cpt.html Internet Privacy Coalition: v̂ ‘v\/vy.privacy.org/ipc

Privacy International: www.privacy.org/pi Privacy Rights Clearinghouse: wvyw.privacyrights.org

vices between merchants and consumers. The nature of the remaining problems are as follows:

• The ability to conduct law enforcement against the violators of individual privacy is very limited. Fven though many countries have enacted similar privacy protection legislation, the enforcement of such local legislation is difficult without the aid of international treaties and collaboration since the Internet has no national boundaries. This dif- ficulty is refiected by the inability of some nations in trying to impose selective censorship on the information content available on the Internet.

• Self-regulation might not provide the best solu- tion to privacy concerns. The inability to enforce such regulation in the absence of a widely recog- nized accreditation system would be disastrous to the consumer’s ability to choose creditable Inter- net merchants, and it would lead to an environ- ment of chaos not dissimilar to the Web market of today.

• Today’s privacy enhancing technologies are not only primitive in nature, but also lacking the integrated environment under which most of the Internet consumers’ privacy concerns can be dealt with. Such technologies are often cumbersome to use, unfriendly and require a degree of knowledge exceeding that of the common Internet consumer. The lack of technical standards that deal specifi- cally with the privacy concerns of Internet con- sumers has resulted in many incompatible products providing similar function.

Furthermore, it is vital that privacy enhancing technologies, industry self-regulations, legislation, and legal enforcement regimes be coordinated in order to provide an overall privacy framework that will be used a basis for answering important prag- matic questions such as: When does an individual’s responsibility begin and when does it end? Can legal

enforcement be conducted in a transparent and unob- trusive manner? While we have made tremendous improvements on the privacy issues related to online marketing, there still remains much to be done before we can achieve the vision of the perfect mar- ketplace that will change the face of commerce as we know it today. B

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parison of managerial and consumer attitudes about information privacy. J. Direct Marketing 11, i (Summer 1997), 44-56.

2. Determining how and when privacy matters. J. Direct Marketing 9, 3 (Summer 1995), 46-60.

3. Kakalik, J.S. and Wright, M.A. Responding to privacy: Concerns of con- sumers. Review of Business, (Fall 1996), 15—18.

4. Lee, M.K.O. Information privacy legislation: The case of Hong Kong. Hong Kong Computer J. 9, H (Nov. 1993), 23-26.

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6. Sipior, J.C. and Ward, B.T. The ethical and legal quandary of email pri- vacy. Commun. ACM 38, 12 (Dec. 1995), 48-54.

7. Wang, P. and Petrison L.A. Direct marketing activities and personal pri- vacy: A consumer survey. J. Direct Marketing 7, 1 (Winter 1993), 7-19.

8. Weisband, S.P. and Reinig, B. Managing user perceptions of email pri- vacy. Commun. ACM 38. 12 (Dec. 1995), 40-47.

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HUAIQING W A N G (iswang@is.cityu.eclu.hk) is an associate professor in the Department of Information Systems at the City University of Hong Kong. M A T T H E W K.O. LEE (ismatlee@is.cityu.edu.hk) is an associate professor and the head of the Department of Information Systems at the City University of Hong Kong. C H E N W A N G (cwang@netdox.com) is a principal technologist

with NetDox, a secure messaging start-up company located in Deerfield, IL.

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