Information Security: Challenges in Using Biometrics
Published: 2003-09-09T00:00:00

Fast Facts:

Highlights:
section_title: Why GAO Did This Study
paragraphs: One of the primary functions of any security system is the control of people into or out of protected areas, such as physical buildings, information systems, and our national border. Technologies called biometrics can automate the identification of people by one or more of their distinct physical or behavioral characteristics. The term biometrics covers a wide range of technologies that can be used to verify identity by measuring and analyzing human characteristics--relying on attributes of the individual instead of things the individual may have or know. In the last 2 years, laws have been passed that will require a more extensive use of biometric technologies in the federal government. Last year, GAO conducted a technology assessment on the use of biometrics for border security. GAO was asked to testify about the issues that it raised in the report, the use of biometrics in the federal government, and the current state of the technology.
section_title: What GAO Found
paragraphs: Biometric technologies are available today that can be used in security systems to help protect assets. Biometric technologies vary in complexity, capabilities, and performance and can be used to verify or establish a person's identity. Leading biometric technologies include facial recognition, fingerprint recognition, hand geometry, iris recognition, retina recognition, signature recognition, and speaker recognition. Biometric technologies have been used in federal applications such as access control, criminal identification, and border security. However, it is important to bear in mind that effective security cannot be achieved by relying on technology alone. Technology and people must work together as part of an overall security process. Weaknesses in any of these areas diminishes the effectiveness of the security process. The security process needs to account for limitations in biometric technology. For example, some people cannot enroll in a biometrics system. Similarly, errors sometimes occur during matching operations. Procedures need to be developed to handle these situations. Exception processing that is not as good as biometric-based primary processing could also be exploited as a security hole. We have found that three key considerations need to be addressed before a decision is made to design, develop, and implement biometrics into a security system: (1) decisions must be made on how the technology will be used; (2) a detailed cost-benefit analysis must be conducted to determine that the benefits gained from a system outweigh the costs; and (3) a trade-off analysis must be conducted between the increased security, which the use of biometrics would provide, and the effect on areas such as privacy and convenience. Security concerns need to be balanced with practical cost and operational considerations as well as political and economic interests. A risk management approach can help federal agencies identify and address security concerns. As federal agencies consider the development of security systems with biometrics, they need to define what the high-level goals of this system will be and develop the concept of operations that will embody the people, process, and technologies required to achieve these goals. With these answers, the proper role of biometric technologies in security can be determined. If these details are not resolved, the estimated cost and performance of the resulting system will be at risk.

section_title: Letter
paragraphs: I appreciate the opportunity to participate in today’s hearing on the use of  smart cards and biometrics in the federal government. One of the primary  functions of any security system is the control of people into or out of  protected areas, such as physical buildings, information systems, and our  national border. People are identified by three basic means: by something  they know, something they have, or something they are. People and  systems regularly use these means to identify people in everyday life. For  example, members of a community routinely recognize one another by  how they look or how their voices sound—by something they are.  Automated teller machines (ATM) recognize customers from their  presentation of a bank card—something they have—and their entering a  personal identification number (PIN)—something they know. Using keys  to enter a locked building is another example of using something you have.  More secure systems may combine two or more of these approaches.
Technologies called biometrics can automate the identification of people  by one or more of their distinct physical or behavioral characteristics. The  term biometrics covers a wide range of technologies that can be used to  verify identity by measuring and analyzing human characteristics—relying  on attributes of the individual instead of things the individual may have or  know.
As requested, I will provide an overview of biometric technologies that are  currently available, describe some of the current uses of these  technologies, and discuss the issues and challenges associated with the  implementation of biometrics. My testimony today is based on a body of  work we completed last year examining the use of biometrics for border  control. In that report, we discussed the current maturity of several  biometric technologies, the possible implementation of these technologies  in current border control processes, and the policy implications and key  considerations for using these technologies. We performed our work in  accordance with generally accepted government auditing standards.
subsections: section_title: Biometric Technologies for Personal Identification
paragraphs: When used for personal identification, biometric technologies measure  and analyze human physiological and behavioral characteristics.  Identifying a person’s physiological characteristics is based on direct  measurement of a part of the body—fingertips, hand geometry, facial  geometry, and eye retinas and irises. The corresponding biometric  technologies are fingerprint recognition, hand geometry, and facial, retina,  and iris recognition. Identifying behavioral characteristics is based on data  derived from actions, such as speech and signature, the corresponding  biometrics being speaker recognition and signature recognition.
Biometrics can theoretically be very effective personal identifiers because  the characteristics they measure are thought to be distinct to each person.  Unlike conventional identification methods that use something you have,  such as an identification card to gain access to a building, or something  you know, such as a password to log on to a computer system, these  characteristics are integral to something you are. Because they are tightly  bound to an individual, they are more reliable, cannot be forgotten, and  are less easily lost, stolen, or guessed.
subsections: section_title: How Biometric Technologies Work
paragraphs: Biometric technologies vary in complexity, capabilities, and performance,  but all share several elements. Biometric identification systems are  essentially pattern recognition systems. They use acquisition devices such  as cameras and scanning devices to capture images, recordings, or  measurements of an individual’s characteristics and computer hardware  and software to extract, encode, store, and compare these characteristics.  Because the process is automated, biometric decision-making is generally  very fast, in most cases taking only a few seconds in real time.
Depending on the application, biometric systems can be used in one of  two modes: verification or identification. Verification—also called  authentication—is used to verify a person’s identity—that is, to  authenticate that individuals are who they say they are. Identification is  used to establish a person’s identity—that is, to determine who a person is.  Although biometric technologies measure different characteristics in  substantially different ways, all biometric systems involve similar  processes that can be divided into two distinct stages: enrollment and  verification or identification.
subsections: section_title: Enrollment
paragraphs: In enrollment, a biometric system is trained to identify a specific person.  The person first provides an identifier, such as an identity card. The  biometric is linked to the identity specified on the identification document.  He or she then presents the biometric (e.g., fingertips, hand, or iris) to an  acquisition device. The distinctive features are located and one or more  samples are extracted, encoded, and stored as a reference template for  future comparisons. Depending on the technology, the biometric sample  may be collected as an image, a recording, or a record of related dynamic  measurements. How biometric systems extract features and encode and  store information in the template is based on the system vendor’s  proprietary algorithms. Template size varies depending on the vendor and  the technology. Templates can be stored remotely in a central database or  within a biometric reader device itself; their small size also allows for  storage on smart cards or tokens.
Minute changes in positioning, distance, pressure, environment, and other  factors influence the generation of a template, making each template likely  to be unique, each time an individual’s biometric data are captured and a  new template is generated. Consequently, depending on the biometric  system, a person may need to present biometric data several times in  order to enroll. Either the reference template may then represent an  amalgam of the captured data or several enrollment templates may be  stored. The quality of the template or templates is critical in the overall  success of the biometric application. Because biometric features can  change over time, people may have to reenroll to update their reference  template. Some technologies can update the reference template during  matching operations.
The enrollment process also depends on the quality of the identifier the  enrollee presents. The reference template is linked to the identity specified  on the identification document. If the identification document does not  specify the individual’s true identity, the reference template will be linked  to a false identity.
section_title: Verification
paragraphs: In verification systems, the step after enrollment is to verify that a person  is who he or she claims to be (i.e., the person who enrolled). After the  individual provides whatever identifier he or she enrolled with, the  biometric is presented, which the biometric system captures, generating a  trial template that is based on the vendor’s algorithm. The system then  compares the trial biometric template with this person’s reference  template, which was stored in the system during enrollment, to determine  whether the individual’s trial and stored templates match (see figure 1).
Verification is often referred to as 1:1 (one-to-one) matching. Verification  systems can contain databases ranging from dozens to millions of enrolled  templates but are always predicated on matching an individual’s presented  biometric against his or her reference template. Nearly all verification  systems can render a match–no-match decision in less than a second. A  system that requires employees to authenticate their claimed identities  before granting them access to secure buildings or to computers is a  verification application.
section_title: Identification
paragraphs: In identification systems, the step after enrollment is to identify who the  person is. Unlike verification systems, no identifier need be provided. To  find a match, instead of locating and comparing the person’s reference  template against his or her presented biometric, the trial template is  compared against the stored reference templates of all individuals enrolled  in the system (see figure 2). Identification systems are referred to as 1:N  (one-to-N, or one-to-many) matching because an individual’s biometric is  compared against multiple biometric templates in the system’s database.
There are two types of identification systems: positive and negative.  Positive identification systems are designed to ensure that an individual’s  biometric is enrolled in the database. The anticipated result of a search is a  match. A typical positive identification system controls access to a secure  building or secure computer by checking anyone who seeks access against  a database of enrolled employees. The goal is to determine whether a  person seeking access can be identified as having been enrolled in the  system.
Negative identification systems are designed to ensure that a person’s  biometric information is not present in a database. The anticipated result  of a search is a nonmatch. Comparing a person’s biometric information  against a database of all who are registered in a public benefits program,  for example, can ensure that this person is not “double dipping” by using  fraudulent documentation to register under multiple identities.
Another type of negative identification system is a surveillance system that  uses a watch list. Such systems are designed to identify people on the  watch list and alert authorities for appropriate action. For all other people,  the system is to check that they are not on the watch list and allow them  normal passage. The people whose biometrics are in the database in these  systems may not have provided them voluntarily. For instance, for a  surveillance system, the biometrics may be faces captured from mug shots  provided by a law enforcement agency.
No match is ever perfect in either a verification or an identification  system, because every time a biometric is captured, the template is likely  to be unique. Therefore, biometric systems can be configured to make a  match or no-match decision, based on a predefined number, referred to as  a threshold, that establishes the acceptable degree of similarity between  the trial template and the enrolled reference template. After the  comparison, a score representing the degree of similarity is generated, and  this score is compared to the threshold to make a match or no-match  decision. Depending on the setting of the threshold in identification  systems, sometimes several reference templates can be considered  matches to the trial template, with the better scores corresponding to  better matches.
section_title: Leading Biometric Technologies
subsections: section_title: Facial Recognition
paragraphs: Retina Recognition    Signature Recognition    Speaker Recognition Facial recognition technology identifies people by analyzing features of  the face not easily altered—the upper outlines of the eye sockets, the  areas around the cheekbones, and the sides of the mouth. The technology  is typically used to compare a live facial scan to a stored template, but it  can also be used in comparing static images such as digitized passport  photographs. Facial recognition can be used in both verification and  identification systems. In addition, because facial images can be captured  from video cameras, facial recognition is the only biometric that can be  used for surveillance purposes.
section_title: Fingerprint Recognition
paragraphs: Fingerprint recognition is one of the best known and most widely used  biometric technologies. Automated systems have been commercially  available since the early 1970s, and at the time of our study, we found  there were more than 75 fingerprint recognition technology companies.  Until recently, fingerprint recognition was used primarily in law  enforcement applications.
Fingerprint recognition technology extracts features from impressions  made by the distinct ridges on the fingertips. The fingerprints can be either  flat or rolled. A flat print captures only an impression of the central area  between the fingertip and the first knuckle; a rolled print captures ridges  on both sides of the finger.
An image of the fingerprint is captured by a scanner, enhanced, and  converted into a template. Scanner technologies can be optical, silicon, or  ultrasound technologies. Ultrasound, while potentially the most accurate,  has not been demonstrated in widespread use. Last year, we found that  optical scanners were the most commonly used. During enhancement,  “noise” caused by such things as dirt, cuts, scars, and creases or dry, wet,  or worn fingerprints is reduced, and the definition of the ridges is  enhanced. Approximately 80 percent of vendors base their algorithms on  the extraction of minutiae points relating to breaks in the ridges of the  fingertips. Other algorithms are based on extracting ridge patterns.
section_title: Hand Geometry
paragraphs: Hand geometry systems have been in use for almost 30 years for access  control to facilities ranging from nuclear power plants to day care centers.  Hand geometry technology takes 96 measurements of the hand, including  the width, height, and length of the fingers; distances between joints; and  shapes of the knuckles.
Hand geometry systems use an optical camera and light-emitting diodes  with mirrors and reflectors to capture two orthogonal two-dimensional  images of the back and sides of the hand. Although the basic shape of an  individual’s hand remains relatively stable over his or her lifetime, natural  and environmental factors can cause slight changes.
section_title: Iris Recognition
paragraphs: Iris recognition technology is based on the distinctly colored ring  surrounding the pupil of the eye. Made from elastic connective tissue, the  iris is a very rich source of biometric data, having approximately 266  distinctive characteristics. These include the trabecular meshwork, a  tissue that gives the appearance of dividing the iris radially, with striations,  rings, furrows, a corona, and freckles. Iris recognition technology uses  about 173 of these distinctive characteristics. Formed during the 8th month  of gestation, these characteristics reportedly remain stable throughout a  person’s lifetime, except in cases of injury. Iris recognition can be used in  both verification and identification systems.
Iris recognition systems use a small, high-quality camera to capture a black  and white, high-resolution image of the iris. The systems then define the  boundaries of the iris, establish a coordinate system over the iris, and  define the zones for analysis within the coordinate system.
section_title: Retina Recognition
paragraphs: Retina recognition technology captures and analyzes the patterns of blood  vessels on the thin nerve on the back of the eyeball that processes light  entering through the pupil. Retinal patterns are highly distinctive traits.  Every eye has its own totally unique pattern of blood vessels; even the  eyes of identical twins are distinct. Although each pattern normally  remains stable over a person’s lifetime, it can be affected by disease such  as glaucoma, diabetes, high blood pressure, and autoimmune deficiency  syndrome.
The fact that the retina is small, internal, and difficult to measure makes  capturing its image more difficult than most biometric technologies. An  individual must position the eye very close to the lens of the retina-scan  device, gaze directly into the lens, and remain perfectly still while focusing  on a revolving light while a small camera scans the retina through the  pupil. Any movement can interfere with the process and can require  restarting. Enrollment can easily take more than a minute.
section_title: Signature Recognition
paragraphs: Signature recognition authenticates identity by measuring handwritten  signatures. The signature is treated as a series of movements that contain  unique biometric data, such as personal rhythm, acceleration, and  pressure flow. Unlike electronic signature capture, which treats the  signature as a graphic image, signature recognition technology measures  how the signature is signed.
In a signature recognition system, a person signs his or her name on a  digitized graphics tablet or personal digital assistant. The system analyzes  signature dynamics such as speed, relative speed, stroke order, stroke  count, and pressure. The technology can also track each person’s natural  signature fluctuations over time. The signature dynamics information is  encrypted and compressed into a template.
section_title: Speaker Recognition
paragraphs: Differences in how different people’s voices sound result from a  combination of physiological differences in the shape of vocal tracts and  learned speaking habits. Speaker recognition technology uses these  differences to discriminate between speakers.
During enrollment, speaker recognition systems capture samples of a  person’s speech by having him or her speak some predetermined  information into a microphone a number of times. This information,  known as a passphrase, can be a piece of information such as a name,  birth month, birth city, or favorite color or a sequence of numbers. Text  independent systems are also available that recognize a speaker without  using a predefined phrase. This phrase is converted from analog to digital  format, and the distinctive vocal characteristics, such as pitch, cadence,  and tone, are extracted, and a speaker model is established. A template is  then generated and stored for future comparisons.
Speaker recognition can be used to verify a person’s claimed identity or to  identify a particular person. It is often used where voice is the only  available biometric identifier, such as telephone and call centers.
section_title: Accuracy of Biometric Technology
paragraphs: Biometrics is a very young technology, having only recently reached the  point at which basic matching performance can be acceptably deployed. It  is necessary to analyze several metrics to determine the strengths and  weaknesses of each technology and vendor for a given application.
The three key performance metrics are false match rate (FMR), false  nonmatch rate (FNMR), and failure to enroll rate (FTER). A false match  occurs when a system incorrectly matches an identity, and FMR is the  probability of individuals being wrongly matched. In verification and  positive identification systems, unauthorized people can be granted access  to facilities or resources as the result of incorrect matches. In a negative  identification system, the result of a false match may be to deny access.  For example, if a new applicant to a public benefits program is falsely  matched with a person previously enrolled in that program under another  identity, the applicant may be denied access to benefits.
A false nonmatch occurs when a system rejects a valid identity, and FNMR  is the probability of valid individuals being wrongly not matched. In  verification and positive identification systems, people can be denied  access to some facility or resource as the result of a system’s failure to  make a correct match. In negative identification systems, the result of a  false nonmatch may be that a person is granted access to resources to  which she should be denied. For example, if a person who has enrolled in  a public benefits program under another identity is not correctly matched,  she will succeed in gaining fraudulent access to benefits.
False matches may occur because there is a high degree of similarity  between two individuals’ characteristics. False nonmatches occur because  there is not a sufficiently strong similarity between an individual’s  enrollment and trial templates, which could be caused by any number of  conditions. For example, an individual’s biometric data may have changed  as a result of aging or injury. If biometric systems were perfect, both error  rates would be zero. However, because biometric systems cannot identify  individuals with 100 percent accuracy, a trade-off exists between the two.
False match and nonmatch rates are inversely related; they must therefore  always be assessed in tandem, and acceptable risk levels must be balanced  with the disadvantages of inconvenience. For example, in access control,  perfect security would require denying access to everyone. Conversely,  granting access to everyone would result in denying access to no one.  Obviously, neither extreme is reasonable, and biometric systems must  operate somewhere between the two.
For most applications, how much risk one is willing to tolerate is the  overriding factor, which translates into determining the acceptable FMR.  The greater the risk entailed by a false match, the lower the tolerable FMR.  For example, an application that controlled access to a secure area would  require that the FMR be set low, which would result in a high FNMR.  However, an application that controlled access to a bank’s ATM might  have to sacrifice some degree of security and set a higher FMR (and hence  a lower FNMR) to avoid the risk of irritating legitimate customers by  wrongly rejecting them. As figure 3 shows, selecting a lower FMR  increases the FNMR. Perfect security would require setting the FMR to 0,  in which case the FNMR would be 1. At the other extreme, setting the  FNMR to 0 would result in an FMR of 1.
Vendors often use equal error rate (EER), an additional metric derived  from FMR and FNMR, to describe the accuracy of their biometric systems.  EER refers to the point at which FMR equals FNMR. Setting a system’s  threshold at its EER will result in the probability that a person is falsely  matched equaling the probability that a person is falsely not matched.  However, this statistic tends to oversimplify the balance between FMR and  FNMR, because in few real-world applications is the need for security  identical to the need for convenience.
FTER is a biometric system’s third critical accuracy metric. FTER  measures the probability that a person will be unable to enroll. Failure to  enroll (FTE) may stem from an insufficiently distinctive biometric sample  or from a system design that makes it difficult to provide consistent  biometric data. The fingerprints of people who work extensively at manual  labor are often too worn to be captured. A high percentage of people are  unable to enroll in retina recognition systems because of the precision  such systems require. People who are mute cannot use voice systems, and  people lacking fingers or hands from congenital disease, surgery, or injury  cannot use fingerprint or hand geometry systems. Although between 1 and  3 percent of the general public does not have the body part required for  using any one biometric system, they are normally not counted in a  system’s FTER.
subsections: section_title: Using Multiple Biometrics
paragraphs: Because biometric systems based solely on a single biometric may not  always meet performance requirements, the development of systems that  integrate two or more biometrics is emerging as a trend. Multiple  biometrics could be two types of biometrics, such as combining facial and  iris recognition. Multiple biometrics could also involve multiple instances  of a single biometric, such as 1, 2, or 10 fingerprints, 2 hands, and 2 eyes.  One prototype system integrates fingerprint and facial recognition  technologies to improve identification. A commercially available system  combines face, lip movement, and speaker recognition to control access to  physical structures and small office computer networks. Depending on the  application, both systems can operate for either verification or  identification. Experimental results have demonstrated that the identities  established by systems that use more than one biometric could be more  reliable, be applied to large target populations, and improve response time.
section_title: Federal Applications of Biometric Technologies
paragraphs: Biometrics have been used in several federal applications including access  control to facilities and computers, criminal identification, and border  security.  In the last 2 years, laws have been passed that will require a  more extensive use of biometric technologies in the federal government.
subsections: section_title: Access Control
paragraphs: Biometric systems have long been used to complement or replace badges  and keys in controlling access to entire facilities or specific areas within a  facility. The entrances to more than half the nuclear power plants in the  United States employ biometric hand geometry systems. Figure 4  illustrates the use of fingerprint recognition for physical access.
As noted in our technology assessment, recent reductions in the price of  biometric hardware have spurred logical access control applications.  Fingerprint, iris, and speaker recognition are replacing passwords to  authenticate individuals accessing computers and networks. The Office of  Legislative Counsel of the U.S. House of Representatives, for example, is  using an iris recognition system to protect confidential files and working  documents. Other federal agencies, including the Department of Defense,  Department of Energy, and Department of Justice, as well as the  intelligence community, are adopting similar technologies.
The Department of Homeland Security’s Transportation Security  Administration (TSA) is working to establish a systemwide common  credential to be used across all transportation modes for all personnel  requiring unescorted physical and/or logical access to secure areas of the  national transportation system, such as airports, seaports, and railroad  terminals. Called the Transportation Worker Identification Credential  (TWIC), the program was developed in response to recent laws and will  include the use of smart cards and biometrics to provide a positive match  of a credential to a person for 10-15 million transportation workers across  the United States.
section_title: Criminal Identification
paragraphs: Fingerprint identification has been used in law enforcement over the past  100 years and has become the de facto international standard for  positively identifying individuals. The Federal Bureau of Investigation  (FBI) has been using fingerprint identification since 1928. The first  fingerprint recognition systems were used in law enforcement about 4  decades ago.
The FBI’s Integrated Automated Fingerprint Identification System (IAFIS)  is an automated 10-fingerprint matching system that stores rolled  fingerprints. The more than 40 million records in its criminal master file  are connected electronically with all 50 states and some federal agencies.
IAFIS was designed to handle a large volume of fingerprint checks against  a large database of fingerprints. Last year, we found that IAFIS processes,  on average, approximately 48,000 fingerprints per day and has processed  as many as 82,000 in a single day. IAFIS’s target response time for criminal  fingerprints submitted electronically is 2 hours; for civilian fingerprint  background checks, 24 hours.
The Immigration and Naturalization Service (INS) began developing the  Automated Biometric Fingerprint Identification System (IDENT) around  1990 to identify illegal aliens who are repeatedly apprehended trying to  enter the United States illegally. INS’s goal was to enroll virtually all  apprehended aliens. IDENT can also identify aliens who have outstanding  warrants or who have been deported. When such aliens are apprehended,  a photograph and two index fingerprints are captured electronically and  queried against three databases (see figure 5). IDENT has over 4.5 million  entries. A fingerprint query of IDENT normally takes about 2 minutes.  IDENT is also being used as a part of the National Security Entry-Exit  Registration System (NSEERS) that was implemented last year.
section_title: Border Security
paragraphs: INS Passenger Accelerated Service System (INSPASS), a pilot program in  place since 1993, has more than 45,000 frequent fliers enrolled at nine  airports, and has admitted more than 300,000 travelers. It is open to  citizens of the United States, Canada, Bermuda, and visa waiver program  countries who travel to the United States on business three or more times  a year. INSPASS permits frequent travelers to circumvent customs  procedures and immigration lines. To participate, users undergo a  background screening and registration. Once enrolled, they can present  their biometric at an airport kiosk for comparison against a template  stored in a central database.
In a joint INS and State Department effort to comply with the Illegal  Immigration Reform and Immigrant Responsibility Act of 1996, every  border crossing card issued after April 1, 1998, contains a biometric  identifier and is machine-readable. The cards, also called laser visas, allow  Mexican citizens to enter the United States for the purpose of business or  pleasure without being issued further documentation and stay for 72 hours  or less, going no farther than 25 miles from the border. Consular staff in  Mexico photograph applicants and take prints of the two index fingers and  then electronically forward applicants’ data to INS. Both State and INS  conduct checks on each applicant, and the fingerprints are compared with  prints of previously enrolled individuals to ensure that the applicant is not  applying for multiple cards under different names. The cards store a  holder’s identifying information along with a digital image of his or her  picture and the minutiae of the two index fingerprints. As of May 2002,  State had issued more than 5 million cards.
The Department of State has been running pilots of facial recognition  technology at 23 overseas consular posts for several years. As a visa  applicant’s information is entered into the local system at the posts and  replicated in State’s Consular Consolidated Database (CCD), the  applicant’s photograph is compared with the photographs of previous  applicants stored in CCD to prevent fraudulent attempts to obtain visas.  Some photographs are also being compared to a watch list.
Laws passed in the last 2 years require a more extensive use of biometrics  for border control. The Attorney General and the Secretary of State  jointly, through the National Institute of Standards and Technology (NIST)  are to develop a technology standard, including biometric identifier  standards. When developed, this standard is to be used to verify the  identity of persons applying for a U.S. visa for the purpose of conducting a  background check, confirming identity, and ensuring that a person has not  received a visa under a different name. By October 26, 2004, the  Departments of State and Justice are to issue to aliens only machine- readable, tamper-resistant visas and other travel and entry documents that  use biometric identifiers. At the same time, Justice is to install at all ports  of entry equipment and software that allow the biometric comparison and  authentication of all U.S. visas and other travel and entry documents  issued to aliens and machine-readable passports. The Department of  Homeland Security is developing the United States Visitor and Immigrant  Status Indication Technology (US-VISIT) system to address this  requirement.
section_title: Challenges and Issues in Using Biometrics
paragraphs: While biometric technology is currently available and used in a variety of  applications, questions remain regarding the technical and operational  effectiveness of biometric technologies in large-scale applications. We  have found that a risk management approach can help define the need and  use for biometrics for security. In addition, a decision to use biometrics  should consider the costs and benefits of such a system and its potential  effect on convenience and privacy.
subsections: section_title: Risk Management Is the Foundation of Effective Strategy
paragraphs: The approach to good security is fundamentally similar, regardless of the  assets being protected, whether information systems security, building  security, or homeland security. As we have previously reported, these  principles can be reduced to five basic steps that help to determine  responses to five essential questions (see figure 6).
What Am I Protecting?
The first step in risk management is to identify assets that must be  protected and the impact of their potential loss.
Who Are My Adversaries?
The second step is to identify and characterize the threat to these assets.  The intent and capability of an adversary are the principal criteria for  establishing the degree of threat to these assets.
Step three involves identifying and characterizing vulnerabilities that  would allow identified threats to be realized. In other words, what  weaknesses can allow a security breach?
What Are My Priorities?
In the fourth step, risk must be assessed and priorities determined for  protecting assets. Risk assessment examines the potential for the loss or  damage to an asset. Risk levels are established by assessing the impact of  the loss or damage, threats to the asset, and vulnerabilities.
What Can I Do?
The final step is to identify countermeasures to reduce of eliminate risks.  In doing so, the advantages and benefits of these countermeasures must  also be weighed against their disadvantages and costs.
section_title: Protection, Detection, and Reaction Are Integral Security Concepts
paragraphs: Countermeasures identified through the risk management process support  the three integral concepts of a holistic security program: protection,  detection, and reaction. Protection provides countermeasures such as  policies, procedures, and technical controls to defend against attacks on  the assets being protected. Detection monitors for potential breakdowns  in protective mechanisms that could result in security breaches. Reaction,  which requires human involvement, responds to detected breaches to  thwart attacks before damage can be done. Because absolute protection is  impossible to achieve, a security program that does not incorporate  detection and reaction is incomplete.
Biometrics can support the protection component of a security program. It  is important to realize that deploying them will not automatically eliminate  all security risks. Technology is not a solution in isolation. Effective  security also entails having a well-trained staff to follow and enforce  policies and procedures. Weaknesses in the security process or failures by  people to operate the technology or implement the security process can  diminish the effectiveness of technology.
Furthermore, there is a need for the security process to account for  limitations in technology. Biometrics can help ensure that people can only  enroll into a security system once and to ensure that a person presenting  himself before the security system is the same person that enrolled into  the system. However, biometrics cannot necessarily link a person to his or  her true identity. While biometrics would make it more difficult for people  to establish multiple identities, if the one identity a person claimed were  not his or her true identity, then the person would be linked to the false  identity in the biometric system. The quality of the identifier presented  during the enrollment process is key to the integrity of a biometrics  system.
Procedures for exception processing would also need to be carefully  planned. As we described, not all people can enroll in a biometrics system.  Similarly, false matches and false nonmatches will also sometimes occur.  Procedures need to be developed to handle these situations. Exception  processing that is not as good as biometric-based primary processing  could be exploited as a security hole.
section_title: Deciding to Use Biometric Technology
paragraphs: A decision to use biometrics in a security solution should also consider the  benefits and costs of the system and the potential effects on convenience  and privacy.
subsections: section_title: Weighing Costs and Benefits
paragraphs: Best practices for information technology investment dictate that prior to  making any significant project investment, the benefit and cost  information of the system should be analyzed and assessed in detail. A  business case should be developed that identifies the organizational needs  for the project and a clear statement of high-level system goals should be  developed. The high-level goals should address the system’s expected  outcomes such as the binding of a biometric feature to an identity or the  identification of undesirable individuals on a watch list. Certain  performance parameters should also be specified such as the time  required to verify a person’s identity or the maximum population that the  system must handle.
Once the system parameters are developed, a cost estimate can be  developed. Not only must the costs of the technology be considered, but  also the costs of the effects on people and processes. Both initial costs and  recurring costs need to be estimated. Initial costs need to account for the  engineering efforts to design, develop, test, and implement the system;  training of personnel; hardware and software costs; network  infrastructure improvements; and additional facilities required to enroll  people into the biometric system. Recurring cost elements include  program management costs, hardware and software maintenance,  hardware replacement costs, training of personnel, additional personnel to  enroll or verify the identities of people in the biometric system, and  possibly the issuance of token cards for the storage of biometrics.
Weighed against these costs are the security benefits that accrue from the  system. Analyzing this cost-benefit trade-off is crucial when choosing  specific biometrics-based solutions. The consequences of performance  issues—for example, accuracy problems, and their effect on processes and  people—are also important in selecting a biometrics solution.
section_title: Effects on Privacy and Convenience
paragraphs: The Privacy Act of 1974 limits federal agencies’ collection, use, and  disclosure of personal information, such as fingerprints and photographs.  Accordingly, the Privacy Act generally covers federal agency use of  personal biometric information. However, the act includes exemptions for  law enforcement and national security purposes. Representatives of civil  liberties groups and privacy experts have expressed concerns regarding  (1) the adequacy of protections for security, data sharing, identity theft,  and other identified uses of biometric data and (2) secondary uses and  “function creep.” These concerns relate to the adequacy of protections  under current law for large-scale data handling in a biometric system.  Besides information security, concern was voiced about an absence of  clear criteria for governing data sharing. The broad exemptions of the  Privacy Act, for example, provide no guidance on the extent of the  appropriate uses law enforcement may make of biometric information.  Because there is no general agreement on the appropriate balance of  security and privacy to build into a system using biometrics, further policy  decisions are required. The range of unresolved policy issues suggests that  questions surrounding the use of biometric technology center as much on  management policies as on technical issues.
Finally, consideration must be given to the convenience and ease of using  biometrics and their effect on the ability of the agency to complete its  mission. For example, some people find biometric technologies difficult, if  not impossible, to use. Still others resist biometrics because they believe  them to be intrusive, inherently offensive, or just uncomfortable to use.  Lack of cooperation or even resistance to using biometrics can affect a  system’s performance and widespread adoption.
Furthermore, if the processes to use biometrics are lengthy or erroneous,  they could negatively affect the ability of the assets being protected to  operate and fulfill its mission. For example, last year, we found that there  are significant challenges in using biometrics for border security. The use  of biometric technologies could potentially impact the length of the  inspection process. Any lengthening in the process of obtaining travel  documents or entering the United States could affect travelers  significantly. Delays inconvenience travelers and could result in fewer  visits to the United States or lost business to the nation. Further studies  could help determine whether the increased security from biometrics  could result in fewer visits to the United States or lost business to the  nation, potentially adversely affecting the American economy and, in  particular, the border communities. These communities depend on trade  with Canada and Mexico, which totaled $653 billion in 2000.
In conclusion, biometric technologies are available today that can be used  in security systems to help protect assets. However, it is important to bear  in mind that effective security cannot be achieved by relying on  technology alone. Technology and people must work together as part of an  overall security process. As we have pointed out, weaknesses in any of  these areas diminishes the effectiveness of the security process. We have  found that three key considerations need to be addressed before a  decision is made to design, develop, and implement biometrics into a  security system:  1.  Decisions must be made on how the technology will be used.  2.  A detailed cost-benefit analysis must be conducted to determine that  the benefits gained from a system outweigh the costs.  3.  A trade-off analysis must be conducted between the increased  security, which the use of biometrics would provide, and the effect on  areas such as privacy and convenience.
Security concerns need to be balanced with practical cost and operational  considerations as well as political and economic interests. A risk  management approach can help federal agencies identify and address  security concerns. As federal agencies consider the development of  security systems with biometrics, they need to define what the high-level  goals of this system would be and develop the concept of operations that  will embody the people, process, and technologies required to achieve  these goals. With these answers, the proper role of biometric technologies  in security can be determined. If these details are not resolved, the  estimated cost and performance of the resulting system will be at risk.
Mr. Chairman, this concludes my statement. I would be pleased to answer  any questions that you or members of the subcommittee may have.
section_title: Contacts
paragraphs: For further information, please contact Keith Rhodes at (202)-512-6412 or  Richard Hung at (202)-512-8073.
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