Installation Manual for digital sets - IP sets - SIP sets AMT/PTD/TR/0001/3/7/ENTo install sets and cartridges in the i7XX range 05/2008 Page 5-115.2.4 EncryptionPrinciple:To prevent calls from being tapped on the IP network, voice is encrypted between two IP points;each of these points may be an IPDS (i740, i760,i780 ) or a VoIP set.Calls may be encrypted end to end or partially.The encryption algorithm is resident on IPDSs (i740, i760, i780), or on NeXspan (PT2, PVI)devices, on Call server, and F6 CPU card (PTX).The i760/i780 display shows ENCRYPTED CALL, while the i740 display shows C (flashing).This is a multi-site function. A master site can send its key to all the sites.Calls are encrypted in an inter-site configuration if:• The function is enabled on the sites concerned• The master/slave configuration is coherent• Both sites have the same encryption key.Prerequisites:Minimum application software release for i740/i740N sets: 6.1A1Minimum application software release for the i760/i780 set IP cartridge: 6.1A1Minimum version of PT2 boot: 43A2.Configuration:On the master site and slave sites, it is necessary to unlock the "Voice encryption function”.On the master site only, it is necessary to define the range of transmission of encryption keys in themulti-site configuration, in the following menu:• (F5,F6) System management/multi-site management/resources on other sites/variousresources/voice encryption resource• (F4) XSERVI (cluster based) / Object=Service Sub-object=EncryptionEnter the encryption configuration parameters in the menu:• (F5,F6) Installer data / Signal management / IP signalling parameters• (F4) XPASIP / IP parametersFor the master site:• Operating mode=master• Encryption = choose one of the 3 possibilities (general prohibition, local authorisation,• general authorisation)