Room 641A: The Secret Telecom Room That Could Turn Tapping Into a System
In 2006, technician Mark Klein gave the Electronic Frontier Foundation drawings he had seen while working at an AT&T facility in San Francisco. The drawings showed a specially secured room connected to equipment that could split traffic from the telecommunications network. The room was known as Room 641A. Klein said the equipment could send a copy of AT&T traffic to the National Security Agency, or NSA.
⬛ CONFIDENTIAL nhat141210/data 8/21/2026 1 min read
In 2006, technician Mark Klein gave the Electronic Frontier Foundation drawings he had seen while working at an AT&T facility in San Francisco. The drawings showed a specially secured room connected to equipment that could split traffic from the telecommunications network. The room was known as Room 641A. Klein said the equipment could send a copy of AT&T traffic to the National Security Agency, or NSA.
In 2006, technician Mark Klein gave the Electronic Frontier Foundation drawings he had seen while working at an AT&T facility in San Francisco. The drawings showed a specially secured room connected to equipment that could split traffic from the telecommunications network. The room was known as Room 641A. Klein said the equipment could send a copy of AT&T traffic to the National Security Agency, or NSA.
In 2006, technician Mark Klein gave the Electronic Frontier Foundation drawings he had seen while working at an AT&T facility in San Francisco. The drawings showed a specially secured room connected to equipment that could split traffic from the telecommunications network. The room was known as Room 641A. Klein said the equipment could send a copy of AT&T traffic to the National Security Agency, or NSA.
In 2006, technician Mark Klein gave the Electronic Frontier Foundation drawings he had seen while working at an AT&T facility in San Francisco. The drawings showed a specially secured room connected to equipment that could split traffic from the telecommunications network. The room was known as Room 641A. Klein said the equipment could send a copy of AT&T traffic to the National Security Agency, or NSA.
In 2006, technician Mark Klein gave the Electronic Frontier Foundation drawings he had seen while working at an AT&T facility in San Francisco. The drawings showed a specially secured room connected to equipment that could split traffic from the telecommunications network. The room was known as Room 641A. Klein said the equipment could send a copy of AT&T traffic to the National Security Agency, or NSA.