*Jean-Francois Blanchette*

- Published in print:
- 2012
- Published Online:
- August 2013
- ISBN:
- 9780262017510
- eISBN:
- 9780262301565
- Item type:
- book

- Publisher:
- The MIT Press
- DOI:
- 10.7551/mitpress/9780262017510.001.0001
- Subject:
- Information Science, Information Science

The gradual disappearance of paper and its familiar evidential qualities affects almost every dimension of contemporary life. From health records to ballots, almost all documents are now digitized at ...
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The gradual disappearance of paper and its familiar evidential qualities affects almost every dimension of contemporary life. From health records to ballots, almost all documents are now digitized at some point of their life cycle, easily copied, altered, and distributed. This book examines the challenge of defining a new evidentiary framework for electronic documents, focusing on the design of a digital equivalent to handwritten signatures. From the blackboards of mathematicians to the halls of legislative assemblies, the book traces the path of such an equivalent: digital signatures based on the mathematics of public-key cryptography. In the mid-1990s, cryptographic signatures formed the centerpiece of a worldwide wave of legal reform and of an ambitious cryptographic research agenda that sought to build privacy, anonymity, and accountability into the very infrastructure of the Internet. Yet markets for cryptographic products collapsed in the aftermath of the dot-com boom and bust along with cryptography’s social projects. The book describes the trials of French bureaucracies as they wrestled with the application of electronic signatures to real estate contracts, birth certificates, and land titles, and tracks the convoluted paths through which electronic documents acquire moral authority. These paths suggest that the material world need not merely succumb to the virtual but, rather, can usefully inspire it. Indeed, the book argues, in renewing their engagement with the material world, cryptographers might also find the key to broader acceptance of their design goals.Less

The gradual disappearance of paper and its familiar evidential qualities affects almost every dimension of contemporary life. From health records to ballots, almost all documents are now digitized at some point of their life cycle, easily copied, altered, and distributed. This book examines the challenge of defining a new evidentiary framework for electronic documents, focusing on the design of a digital equivalent to handwritten signatures. From the blackboards of mathematicians to the halls of legislative assemblies, the book traces the path of such an equivalent: digital signatures based on the mathematics of public-key cryptography. In the mid-1990s, cryptographic signatures formed the centerpiece of a worldwide wave of legal reform and of an ambitious cryptographic research agenda that sought to build privacy, anonymity, and accountability into the very infrastructure of the Internet. Yet markets for cryptographic products collapsed in the aftermath of the dot-com boom and bust along with cryptography’s social projects. The book describes the trials of French bureaucracies as they wrestled with the application of electronic signatures to real estate contracts, birth certificates, and land titles, and tracks the convoluted paths through which electronic documents acquire moral authority. These paths suggest that the material world need not merely succumb to the virtual but, rather, can usefully inspire it. Indeed, the book argues, in renewing their engagement with the material world, cryptographers might also find the key to broader acceptance of their design goals.

*Keith M. Martin*

- Published in print:
- 2017
- Published Online:
- July 2017
- ISBN:
- 9780198788003
- eISBN:
- 9780191829956
- Item type:
- chapter

- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198788003.003.0001
- Subject:
- Mathematics, Computational Mathematics / Optimization, Logic / Computer Science / Mathematical Philosophy

This chapter serves as an introduction to the environment in which cryptography finds common use today. We discuss the need for cryptography, as well as the basic language and concepts that are used ...
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This chapter serves as an introduction to the environment in which cryptography finds common use today. We discuss the need for cryptography, as well as the basic language and concepts that are used to describe a cryptographic system. We introduce the core security services, such as confidentiality, data integrity, and authentication, which are delivered by cryptography in order to support modern security technologies. We introduce both symmetric and public-key cryptosystems, and discuss the differences between them. Finally, we consider ways in which cryptosystems can be attacked or compromised.Less

This chapter serves as an introduction to the environment in which cryptography finds common use today. We discuss the need for cryptography, as well as the basic language and concepts that are used to describe a cryptographic system. We introduce the core security services, such as confidentiality, data integrity, and authentication, which are delivered by cryptography in order to support modern security technologies. We introduce both symmetric and public-key cryptosystems, and discuss the differences between them. Finally, we consider ways in which cryptosystems can be attacked or compromised.

*Lance Fortnow*

- Published in print:
- 2017
- Published Online:
- May 2018
- ISBN:
- 9780691175782
- eISBN:
- 9781400846610
- Item type:
- chapter

- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691175782.003.0008
- Subject:
- Computer Science, Programming

This chapter analyzes how, in 1976, Whitfield Diffie and Martin Hellman suggested that one could use NP to hide one's own secrets. The field of cryptography, the study of secret messages, changed ...
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This chapter analyzes how, in 1976, Whitfield Diffie and Martin Hellman suggested that one could use NP to hide one's own secrets. The field of cryptography, the study of secret messages, changed forever. Diffie and Hellman, building on earlier work of Roger Merkle, proposed a method to get around the problem of network security using what they called “public-key” cryptography. A computer would generate two keys, a public key and a private key. The computer would store the private key, never putting that key on the network. The public key would be sent over the network broadcast to everyone. Diffie and Hellman's idea was to develop a cryptosystem that used the public key for encrypting messages, turning the real message into a coded one. The public key would not be able to decrypt the message. Only the private key could decrypt the message.Less

This chapter analyzes how, in 1976, Whitfield Diffie and Martin Hellman suggested that one could use NP to hide one's own secrets. The field of cryptography, the study of secret messages, changed forever. Diffie and Hellman, building on earlier work of Roger Merkle, proposed a method to get around the problem of network security using what they called “public-key” cryptography. A computer would generate two keys, a public key and a private key. The computer would store the private key, never putting that key on the network. The public key would be sent over the network broadcast to everyone. Diffie and Hellman's idea was to develop a cryptosystem that used the public key for encrypting messages, turning the real message into a coded one. The public key would not be able to decrypt the message. Only the private key could decrypt the message.