It rotates through units. I was in the 101st when I went. We were replaced by the 82nd, who was then replaced by 10th Mountain etc.
That mission was given to Army National Guard units who fill it for a year and change out. They are mostly in South Camp, Sharm el Sheik, while Active component Army staff are mostly in North Camp, near Rafah, which is the camp the article us likely talking about. Or it could be one of the much smaller encampments. BTW, I was the FPNCOIC 06-07.