The purpose of the article is to develop a mathematical model of VPN in communication networks of special purpose. which allows to determine the margin of throughput. for scheduled VPN-tunnels. In contrast to the well-known approaches to estimating the bandwidth margin (hose model of VPN). https://www.bekindtopets.com/limited-stock-Original-U-S-Vietnam-War-Era-Operation-Igloo-White-Seismic-Sensor-Inert-Rocket-great-price/