ANNEX C. Security of Green and Federal Telephone systems. All users of Green or Federal line telephones are reminded that these systems are NOT secret. 2. Inside calls in a building on the Green system are more secret than the black system in that the two are not inter-connected and that operators for the Green exchange are especially selected. Outside Government buildings the Green system is in a number of cases connected to ordinary exchanges and is therefore little more secure than the ordinary system; further there is always danger of overhearing owing to faults and contacts.
- Collection ID
- CAB81
- Conflict
- Second World War
- Document Reference
- CAB 81/99/37
- Document Types
- Memorandum
- File Reference
- CAB 81/99
- Identifier
- 10.1080/swwf.cab81.0099.037
- Keywords
- Security Telephone Communications Leakage Of Information
- Languages
- English
- Organizations
- Chiefs of Staff Joint Intelligence Sub-Committee
- Pages
- 3
- Persons Discussed
- C Edwards
- Published in
- United Kingdom
- Themes
- British Domestic Security