The "login" you found (at 1:09:45) was actually for the alternate reality game valve released with Portal:
https://www.aperturescience.com/ (it's very old now and flash has been disabled in all major browsers)
The Login was "CJOHNSON" with the password "TIER3"
It was used as a way to promote Portal 2 and give some hints behind some lore of the series. Before Portal 2 was released there was also a comic you can check out that connects Portal 1 and 2. It can be read here: https://www.thinkwithportals.com/comic/
![[Early Access] Portal | Full Playthrough](https://img5.samsuka.com/storage/8/bs/oo/c6f9d9-019e9005-b21f-74f6-b574-181b8a02a6bf.jpg)
