what is the division being mentioned in 24?

division is a unit of protection which is above ctu and which acts in linking the lapd,ctu-la,presidents office.normally president will be updaed by division about situtions of all ctu's of all states but in cases of emergencies like in 24 president will be in direct contact with ctu.and division only recruites all the members of ctu.

Well apparently Division is a branch of the Counter Terrorist Unit which oversees the operation and, if necessary, command of domestic units (CTU Los Angeles, CTU Boston, etc.) in a designated area. Division can order a lockdown and reviews the cases of domestic unit agents who have been relieved of duty. The authority figure in CTU stations is the Regional Division Director (Chappelle, Buchanan). Division reports to District Command (who in turn reports directly to CTU Headquarters in Washington, D.C. Hope this helps.