Yiqun Lisa Yin facts for kids

Yiqun Lisa Yin is a super smart Chinese-American expert in computer security and codes, called a cryptographer. She helps make sure our digital information stays safe. She's famous for finding a weakness in a very important computer code called SHA-1. She also helped create another code called RC6 and worked on rules for how computers should keep secrets using special math.

Her Journey in Learning and Work

Yiqun Lisa Yin started her amazing journey at Peking University in China. She studied there from 1985 to 1989. She earned a special degree in applied mathematics, which is like using math to solve real-world problems.

After that, she moved to the Massachusetts Institute of Technology (MIT) in the United States. She continued her studies there and earned her Ph.D. in applied mathematics in 1994. Her big project for her Ph.D. was about how computers learn and make decisions.

Where She Worked

After finishing her studies, Dr. Yin worked at several important places.

• From 1994 to 1999, she was a researcher at RSA Laboratories. This company is well-known for its work in computer security.
• Then, from 1999 to 2002, she was a director at NTT's Palo Alto Laboratory. NTT is a big telecommunications company.
• Later, she became an independent consultant. This means she worked for herself, helping different companies with their security needs.
• She also visited and worked at famous universities like Princeton University and Tsinghua University.
• From 2016 to 2019, Dr. Yin was the chief security officer and chief cryptographer at a company called Symbiont. This means she was in charge of all their security and code-making projects.

Her Big Contributions to Computer Security

Dr. Yin has made some very important discoveries and helped create new standards in computer security.

Setting Standards for Digital Secrets

She was a key editor for a project called IEEE P1363. This project created rules and standards for something called public-key cryptography. This is a special way for computers to send secret messages safely, even if they haven't met before. It's like having two keys: one you share with everyone (public) and one you keep secret (private).

Helping Create the RC6 Code

Dr. Yin was also one of the main people who designed a computer code called RC6. She worked with Ron Rivest, Matt Robshaw, and Ray Sidney. RC6 is a type of "block cipher." Imagine you have a message, and you break it into small blocks. A block cipher scrambles each block using a secret key.

RC6 was so good that it was one of the top five codes chosen for a big competition. This competition was to find the best new standard for encrypting (scrambling) information, called the Advanced Encryption Standard (AES).

Finding a Weakness in SHA-1

One of Dr. Yin's most famous achievements happened in 2005. She worked with Wang Xiaoyun and Hongbo Yu. They found a major weakness in a very important computer code called SHA-1.

SHA-1 is a "cryptographic hash function." Think of it like a unique digital fingerprint for any piece of data. If you change even one tiny thing in the data, its SHA-1 fingerprint will look completely different. This is used to check if files have been tampered with.

Dr. Yin and her team showed that it was possible, though difficult, to find two different pieces of data that would create the exact same SHA-1 fingerprint. This is called a "hash collision." Finding these collisions meant that SHA-1 was not as secure as people thought. Because of their work, SHA-1 is now considered "broken" and is no longer used for important security tasks. This helped make the internet safer for everyone!