Cypherpunks Write Code: Phil Zimmerman and PGP

23 Apr 2024

Cryptography can be used to have not only decentralized and private money but also private communications. The activists known as cypherpunks knew this too well, and that’s why not only Bitcoin came out from that mailing list started in the ’90s. A bunch of free and useful cryptographic tools are the legacy of cypherpunks, including the one created by Phil Zimmerman —a remarkable cypherpunk even to this day.

Born on February 12, 1954, in Camden, New Jersey, Zimmermann studied computer science at Florida Atlantic University, where he earned his degree in 1978. His career trajectory began with software engineering roles in various companies, including a stint at the nuclear power company, System Simulation Corporation, where he worked on cryptographic security systems.

However, the interesting part is that he was also an anti-nuclear activist. It’s known that he was arrested for partaking in an anti-nuclear protest in Nevada, alongside prominent figures like Carl Sagan and Martin Sheen. This commitment to activism underscored Zimmermann's convictions, solidifying his standing within the anti-nuclear movement.

Amidst the shifting geopolitical landscape of the early 1990s, Zimmermann's focus pivoted towards cryptography, recognizing its potential to safeguard private communications in an increasingly interconnected world. It was during this period that he would join the cypherpunks and create his ‘magnum opus’.

Pretty Good Privacy (PGP)

This is a thing even Satoshi Nakamoto used to protect his emails, and it’s still widely used as a standard to achieve private communications. Developed in 1991, PGP is an encryption software designed to secure email messages. Zimmermann's motivation behind PGP was rooted in his concerns about government surveillance and the need for accessible cryptographic tools to protect individual privacy. In his own words:

“It's personal. It's private. And it's no one's business but yours. You may be planning a political campaign, discussing your taxes, or having a secret romance. Or you may be communicating with a political dissident in a repressive country. Whatever it is, you don't want your private electronic mail (email) or confidential documents read by anyone else (...) PGP empowers people to take their privacy into their own hands. There has been a growing social need for it. That's why I wrote it.”

As for its internal features, PGP uses a pair of cryptographic keys for each user—a public key and a private key. The public key, which is freely distributed, is used by others to encrypt messages intended for the user. Meanwhile, the private key, kept confidential by the user, is used for decrypting these messages.

When someone wants to send an encrypted message to a PGP user, they obtain the recipient's public key. Using this key, they encrypt the message, ensuring that only the intended recipient, who possesses the corresponding private key, can decrypt and read it. This process provides confidentiality for the message.

Additionally, PGP supports digital signatures, enabling users to verify the authenticity and integrity of emails. By hashing the message and encrypting the hash with their private key, senders create digital signatures that recipients can verify using the sender's public key.

After PGP

Back then, the US government considered cryptographic tools as weapons, and that’s why Zimmerman was investigated by authorities for the free distribution of PGP. Luckily, they dropped the case in 1996 without charges, and the cypherpunk founded PGP Inc., along with a new release of PGP. The company in charge of maintaining the software was eventually sold to Symantec in 2010.

Following the success of PGP, Zimmermann has also been involved in various ventures aimed at bolstering digital security and privacy. In 2012, he co-founded Silent Circle alongside Mike Janke and Jon Callas, focusing on developing secure hardware and subscription-based software solutions. Additionally, Zimmermann collaborated with other key figures from Silent Circle and Lavabit (an encrypted webmail service) to establish the Dark Mail Alliance in 2013, with the objective of creating a new protocol to enhance email encryption, addressing limitations in PGP.

Beyond his cryptographic endeavors, Zimmermann extended his influence to social networking platforms, advocating for ethical and privacy-centric alternatives to mainstream platforms like Facebook. His involvement in the social network Okuna, previously known as Openbook, aimed to provide users with a platform that prioritized privacy and democratic values over profit-driven models.

Zimmermann's contributions have been widely recognized, with numerous awards acknowledging his pioneering work in cryptography and advocacy for digital rights. From inductions into halls of fame to prestigious accolades such as the Louis Brandeis Award from Privacy International and the Norbert Wiener Award for Social and Professional Responsibility, Zimmermann's legacy continues to resonate within the realms of technology and human rights advocacy.

In a world of surveillance

There’s a thing called “the Zimmerman law” that refers to his words about technology and surveillance: “The natural flow of technology tends to move in the direction of making surveillance easier (…) the ability of computers to track us doubles every eighteen months.” If the period is exact or not in reality, it doesn’t matter, because today mass surveillance and censorship have become common feats by governments worldwide.

PGP can help us to protect our privacy and digital rights, but it’s not the only tool available for that. Obyte, for instance, can also help with private communications and decentralized, fast, and secure financial transactions worldwide. Built on a Directed Acyclic Graph (DAG) structure, Obyte ensures global transactions without the need for miners or any other middlemen. This structure enables Obyte to increase its decentralization and offers a high level of control to its users.

In addition to its financial features, where tokenization of any asset is also possible, Obyte integrates private communications functionality directly into its platform. Users can leverage Obyte's built-in messaging system in the wallet to communicate securely and privately, thanks to end-to-end encryption, similar to PGP.

This feature enhances user privacy by enabling them to freely communicate without a company or government behind them, thus providing a comprehensive solution for both financial transactions and private messaging. As a result, we can say that Obyte is empowering users with a versatile platform for conducting secure and private interactions worldwide.

Read more from Cypherpunks Write Code series:

Tim May & Crypto-anarchism

Wei Dai & B-money

Nick Szabo & Smart Contracts

Adam Back & Hashcash

Eric Hughes & Remailer

St Jude & Community Memory

Hal Finney & RPOW

Featured Vector Image by Garry Killian / Freepik

Photo by Phil Zimmerman