Quote from: Dr. Pepper on September 07, 2014, 02:19:52 PM

Quote from: bambino on September 07, 2014, 02:01:11 PM

Quote from: lovegood on September 07, 2014, 01:39:18 PM

wtf is a 'pen register'?

"A pen register is an electronic device that records all numbers called from a particular telephone line. The term has come to include any device or program that performs similar functions to an original pen register, including programs monitoring Internet communications."
http://en.wikipedia.org/wiki/Pen_register

Basically they monitored all the internet usage of Ulbricht for a few days, this was "judicially authorized".

"The Pen Registers did not collect the contents of any communications. They collected only routing information, such as the IP addresses being contacted using the account, router, and devices, the ports being accessed, and the MAC addresses of the devices involved.
We used the Pen Registers to track when Ulbricht was connected to the Internet and what IP addresses and ports he was connecting to. By monitoring when Ulbricht appeared to be online, and comparing it to the times when DPR appeared to be logged in to Silk Road (as reflected by his activity on the Silk Road discussion forum), additional evidence was collected corroborating that Ulbricht was in fact DPR.

More at 18 - 21 in the declaration

Isn't that circumstantial? I'm not computer whiz but how did the captchas leak information to the SR servers. Aren't captchas like an external process ie not hosted on whatever server the website uses?

People are convicted on circumstantial evidence all the time. Usually not of crimes that are this serious however it is possible.

Although it is circumstantial, the chances of it being someone other then him does decrease as the number of times he was observed online increases.