Minnie McNeal Kenny Assistant Professor Megumi Ando researches the theoretical foundations of anonymous communications. She leads the Ando Lab, which focuses on designing and analyzing practical communication protocols that offer provable anonymity.
Ando's primary research projects include:
- Anonymous Communication
- Cryptographic Onions
- Provable Anonymity in Asynchronous Communication Settings
Communication Protocols
Hiding who is communicating with whom can be really important, enabling, for example, whistleblowers to safely communicate. But how can you determine if a protocol is secure in this way? The Ando Lab designs and analyzes communication protocols that, subject to some reasonable mathematical assumptions, assure no attacker can differentiate between two plausible communication patterns.
Cryptographic Onions
One practical method to achieve anonymity from an attacker with a broad view of the Internet, such as an ISP-level attacker, is through onion routing, in which the sender first selects a random path and creates a layered encryption “onion” to send a message to a receiver. The onion travels through the chosen path, shedding a layer of encryption at each intermediary party until it reaches the receiver. The Ando Lab designs cryptographic onions with additional properties that enable provable security in challenging—but realistic—settings.
Provable Anonymity in the Asynchronous Communications Setting
Timing attacks can compromise anonymity and are thus threatening in asynchronous communications. The Ando Lab seeks methods to prevent these compromises. One such example is if an adversary can delay a single targeted sender's onions, but not delay or drop any other onions. This will allow the adversary to observe a late onion delivery at the recipient with a (non-negligible) higher probability than with any other recipient. The Ando Lab has found ways to circumvent such attacks by dropping onions that are chronically running behind.