One, proclaimed by Moscow, holds that the airliner was on a spy mission designed to activate Russian air-defense networks and reveal many secrets to American listening posts.

In 1940, Josef Kammhuber used Freyas in a new air-defense network extending through the Netherlands, Belgium, and France.

"To affect their air-defense network, you have to identify and target the important nodes in that network," said an Air Force general.

In the 1950's and 1960's, General Stevenson held several high positions in the United States' air-defense network in Europe.

If it's Iran or Syria, or even Lebanon, penetration of air-defense networks is going to make the mission tricky.

Aleppo Four is right behind a major air-defense network that extends to Damascus.

"The Iraqi southern air-defense network is now seriously degraded," said Pete Williams, the Defense Department spokesman.

Only military radars see the aircraft themselves, and what African country has a proper air-defense network?

More and More Cubans Angola has received large quantities of military equipment, including an advanced air-defense network, from the Soviet Union.

Like its predecessor TD-2000, TD-2000B can also be integrated into larger air-defense network via LIN-VK data link to further increase its effectiveness.