The compound is roughly 300 yards long by 100 yards wide. The large size is to protect against car bombs. The outer wall’s height nine feet topped by three feet of barbed wire and concertina wire and external lighting. Jersey barriers (big concrete blocks) are installed outside and inside the gate. Steel drop bars are added at the gates to control vehicle access and to provide some anti-ram protection. The buildings on the compound itself were strengthened.
The compound has four buildings on it, Building C (a large residence with numerous bedrooms and a safe haven), Building B (another residence with a cantina dining area), the TOC or Tactical Operations Center (Offices and a bedroom used by the security team to monitor outside activity on video monitors), and a barracks (a small house by the main gate of the compound).
Security on the compound consists of five Diplomatic Security special agents and four members of the Libyan Government security force, a friendly militia called the 17th February Brigade. There is an additional security force at another U.S. compound two kilometers away. It serves as a rapid reaction force.
There has been speculation that two other warehouse-like buildings on the compound which were not mentioned in the State Department briefing were being used to hold armaments. [1. Family Security Matters – Arms Flow to Syria May Be Behind Benghazi Cover-Up http://www.familysecuritymatters.org/publications/detail/arms-flow-to-syria-may-be-behind-benghazi-cover-up]