Other Functions of Intelligence Services
Intelligence services also perform other security functions, especially in the field of personal security (checks on people working with classified information), information and communication security, including the protection of government communication, encryption and other aspects of technical security and security counselling. Military intelligence services are often equipped to wage electronic warfare and can provide special forces with intelligence. Intelligence services of large countries can carry out actions to influence, take secret active measures as a classified tool of foreign policy.
Intelligence service of course performs functions for their internal purposes, such as staff, controlling, personnel, legal functions, keeping of files, archiving, logistic and economic functions (regarding finances and property), communication and IT, security (including guard, checking and technical functions) or internal control.
Source: Petr Zeman - lectures, trainings and public speeches