Security By Design Scott A. Vanstone V.P. Cryptographic Research Research in Motion Distinguished Professor Emeritus University of Waterloo

Security by Design When designing a new telecommunications system it is prudent to make security a fundamental part of the design process. Geneva, 6-7 December Addressing security challenges on a global scale

What is Cryptography? Cryptography is the study of mathematical techniques related to aspects of information security such as: – confidentiality – data integrity – entity authentication – data origin authentication Geneva, 6-7 December Addressing security challenges on a global scale

What is Cryptography (2) Cryptography plays a fundamental role in securing information based systems. Often cryptography (and security in general) is an afterthought and as such it is bolted on after the overall system has been completed. Geneva, 6-7 December Addressing security challenges on a global scale

Think of the Postal Analogue You put a letter in an envelope to maintain the integrity of the information in the letter and keep the letter from prying eyes (integrity and encryption). You put your address in the upper left corner of the envelope to authenticate the sender which is you (authentication). You sign the letter so that at a later date you cannot say you did not send it. 6 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

The Digital World We want to mimic all of these services but electronically. This has been done and done more securely and efficiently than postal mail. It is all due to the advent of something called “public-key cryptography”. Canada is and continues to be a leader in this field. 7 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Symmetric-Key Cryptography Communicating parties a priori share secret information. 8 Addressing security challenges on a global scaleGeneva, 6-7 December 2010 secure channel Eve Alice Bob unsecured channel

Public-Key Cryptography Communicating parties a priori share authentic information. 9 Addressing security challenges on a global scaleGeneva, 6-7 December 2010 authentic channel Eve Alice Bob unsecured channel

Symmetric-Key vs Public-Key Symmetric-Key has been used for thousands of years. Public-Key is relatively new dating from Public-key cryptography is based on hard mathematical problems. 10 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Why Symmetric-Key? Typically very fast for bulk encryption (confidentiality). The Advanced Encryption Standard (AES) is well accepted as a superior algorithm for symmetric-key. 11 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Disadvantages of Symmetric Key Key management can be a serious problem. Non-repudiation (digital signature) is very difficult to realize. 12 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Why Public-Key? One disadvantage of symmetric-key cryptography is key management. Public-Key provides an efficient method to distribute keys. Public-key offers a very efficient way to provide non-repudiation. This is one of the great strengths of public-key. 13 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Disadvantages of Public-Key Public-key operations require intense mathematical calculations. They can be thousands of times slower to encrypt data than a well designed symmetric- key scheme. 14 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Hybrid Schemes Use symmetric-key schemes to do bulk encryption. Use public-key techniques to pass keys so that key management is not a problem. 15 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Digital Signatures One of the truly great technologies that public-key cryptography can provide. Handwritten signatures are fixed to the message but not an integral part of the message. Digital signatures combine the message and private information of the signer. 16 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Why Elliptic Curve Cryptography (ECC)? Most security per bit of any known public-key scheme Ideally suited to constrained environments – Computationally efficient – Bandwidth efficient – Battery efficient Well studied Standardized in relevant influential international standards 17 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Elliptic Curve: y2=x3+ax+b 18 Addressing security challenges on a global scaleGeneva, 6-7 December 2010

Suite B PurposeAlgorithmUnclassifiedClassified EncryptionAES128 bit key256 bit key SignaturesECDSA256 bit curve384 bit curve Key ExchangeECDH or ECMQV256 bit curve384 bit curve HashingSHASHA-256SHA

Suite E for Embedded Systems PurposeAlgorithmUnclassified EncryptionAES128 bit key SignaturesECDSA283 bit curve Key ExchangeECDH or ECMQV283 bit curve HashingSHASHA-256 Geneva, 6-7 December Addressing security challenges on a global scale

Examples of Security by Design XM Radio Blackberry Geneva, 6-7 December Addressing security challenges on a global scale

XM Radio XM Radio delivers digital radio to most of North America. XM approached Certicom in the late 90s to design security into the system from the ground up. Geneva, 6-7 December Addressing security challenges on a global scale

BlackBerry RIM built security in from the beginning. Suite B was running on the device even before the NSA endorsement in Geneva, 6-7 December Addressing security challenges on a global scale

Conclusion There is good security available. The simple but often forgotten message is: – Design security into the system from the beginning. – Think the design through careful so that you meet your objectives. Geneva, 6-7 December Addressing security challenges on a global scale