Range of TopSec devices for online encryption of traffic over "land-line" network. They use the Rohde&Schwarz SIT's secure encryption procedures and provide full protection over public "land-line" telephone networks.

Encryption is based on a hybrid method. To attain maximum security, a combination of two algorithms is used an asymmetrical algorithm for key agreement, and a symmetrical algorithm for data encryption.

Family TopSec provides reliable encryption for the following basic services:

- "Land-line" networks:

TopSec 711 – protection over public analoge and DialUp telephone networks

TopSec 703 – protection over public ISDN basic multiterminal access telephone networks;

TopSec 730 – protection over public ISDN primary multiplex access telephone networks;

TopSec 703+ - the same security capabilities as TopSec 703 and the opportunity to secure communication with TopSec GSM and TopSec Mobile;

- IP communications with fixed IP аdresses:

R&S®LineCrypt L – protections communications up to 10 Mbit/s with 256 simultaneous tunnels;