Essays Tagged "Communications of the ACM"
Page 2 of 2
Voting and Technology: Who Gets to Count Your Vote?
Paperless voting machines threaten the integrity of democratic process by what they don't do.
Voting problems associated with the 2000 U.S. Presidential election have spurred calls for more accurate voting systems. Unfortunately, many of the new computerized voting systems purchased today have major security and reliability problems.
The ideal voting technology would have five attributes: anonymity, scalability, speed, audit, and accuracy (direct mapping from intent to counted vote). In the rush to improve the first four, accuracy is being sacrificed. Accuracy is not how well the ballots are counted; it’s how well the process maps voter intent into counted votes and the final tally. People misread ballots, punch cards don’t tabulate properly, machines break down, ballots get lost. Mistakes, even fraud, happen…
Cyber Underwriters Lab?
Underwriters Laboratories (UL) is an independent testing organization created in 1893, when William Henry Merrill was called in to find out why the Palace of Electricity at the Columbian Exposition in Chicago kept catching on fire (which is not the best way to tout the wonders of electricity). After making the exhibit safe, he realized he had a business model on his hands. Eventually, if your electrical equipment wasn’t UL certified, you couldn’t get insurance.
Today, UL rates all kinds of equipment, not just electrical. Safes, for example, are rated based on time to crack and strength of materials. A “TL-15” rating means that the safe is secure against a burglar who is limited to safecracking tools and 15 minutes’ working time. These ratings are not theoretical; employed by UL, actual hotshot safecrackers take actual safes and test them. Applying this sort of thinking to computer networks—firewalls, operating systems, Web servers—is a natural idea. And the newly formed Center for Internet Security (no relation to UL) plans to implement it…
Insurance and the Computer Industry
View or Download in PDF Format
In the future, the computer security industry will be run by the insurance industry. I don’t mean insurance companies will start selling firewalls, but rather the kind of firewall you use—along with the kind of authentication scheme you use, the kind of operating system you use, and the kind of network monitoring scheme you use—will be strongly influenced by the constraints of insurance.
Consider security and safety in the real world. Businesses don’t install alarms in their warehouses because it makes them safer; they do it because they get a break in their insurance rates. Hotels and office buildings don’t install sprinkler systems because they’re concerned about the welfare of their tenants, but because building codes and insurance policies demand it. These are all risk management decisions, and the risk-taker of last resort is the insurance industry…
Risks of PKI: Electronic Commerce
Open any popular article on public-key infrastructure (PKI) and you’re likely to read that a PKI is desperately needed for E-commerce to flourish. Don’t believe it. E-commerce is flourishing, PKI or no PKI. Web sites are happy to take your order if you don’t have a certificate and even if you don’t use a secure connection. Fortunately, you’re protected by credit-card rules.
The main risk in believing this popular falsehood stems from the cryptographic concept of “non-repudiation”.
Under old, symmetric-key cryptography, the analog to a digital signature was a message authentication code (MAC). If Bob received a message with a correct MAC, he could verify that it hadn’t changed since the MAC was computed. If only he and Alice knew the key needed to compute the MAC and if he didn’t compute it, Alice must have. This is fine for the interaction between them, but if the message was “Pay Bob $1,000,000.00, signed Alice” and Alice denied having sent it, Bob could not go to a judge and prove that Alice sent it. He could have computed the MAC himself…
Risks of PKI: Secure E-Mail
Public-key infrastructure (PKI), usually meaning digital certificates from a commercial or corporate certificate authority (CA), is touted as the current cure-all for security problems.
Certificates provide an attractive business model. They cost almost nothing to manufacture, and you can dream of selling one a year to everyone on the Internet. Given that much potential income for CAs, we now see many commercial CAs, producing literature, press briefings and lobbying. But, what good are certificates? In particular, are they any good for E-mail? What about free certificates, as with PGP?…
Risks of Relying on Cryptography
Cryptography is often treated as if it were magic security dust: “sprinkle some on your system, and it is secure; then, you’re secure as long as the key length is large enough—112 bits, 128 bits, 256 bits” (I’ve even seen companies boast of 16,000 bits.) “Sure, there are always new developments in cryptanalysis, but we’ve never seen an operationally useful cryptanalytic attack against a standard algorithm. Even the analyses of DES aren’t any better than brute force in most operational situations. As long as you use a conservative published algorithm, you’re secure.”…
The Trojan Horse Race
1999 is a pivotal year for malicious software ( malware) such as viruses, worms, and Trojan horses. Although the problem is not new, Internet growth and weak system security have evidently increased the risks.
Viruses and worms survive by moving from computer to computer. Prior to the Internet, computers (and viruses!) communicated relatively slowly, mostly through floppy disks and bulletin boards. Antivirus programs were initially fairly effective at blocking known types of malware entering personal computers, especially when there were only a handful of viruses. But now there are over 10,000 virus types; with e-mail and Internet connectivity, the opportunities and speed of propagation have increased dramatically…
Biometrics: Uses and Abuses
Biometrics are seductive. Your voiceprint unlocks the door of your house. Your iris scan lets you into the corporate offices. You are your own key. Unfortunately, the reality isn’t that simple.
Biometrics are the oldest form of identification. Dogs have distinctive barks. Cats spray. Humans recognize faces. On the telephone, your voice identifies you. Your signature identifies you as the person who signed a contract.
In order to be useful, biometrics must be stored in a database. Alice’s voice biometric works only if you recognize her voice; it won’t help if she is a stranger. You can verify a signature only if you recognize it. To solve this problem, banks keep signature cards. Alice signs her name on a card when she opens the account, and the bank can verify Alice’s signature against the stored signature to ensure that the check was signed by Alice…
Cryptography, Security and the Future
From e-mail to cellular communications, from secure Web access to digital cash, cryptography is an essential part of today’s information systems. Cryptography helps provide accountability, fairness, accuracy, and confidentiality. It can prevent fraud in electronic commerce and assure the validity of financial transactions. It can protect your anonymity or prove your identity. It can keep vandals from altering your Web page and prevent industrial competitors from reading your confidential documents. And in the future, as commerce and communications continue to move to computer networks, cryptography will become more and more vital…
Sidebar photo of Bruce Schneier by Joe MacInnis.