A star community is a VPN topology where one or more satellites connect to a center gateway. The center gateway can be a Security Gateway or a Security Management Server. The VPN routing option determines how the traffic is routed between the satellites and the center, and between the satellites themselves. There are three VPN routing options available in a star community12:
To center only: The satellites can only communicate with the center gateway, and not with each other or with any other VPN targets. This option is useful for remote access clients that only need to access resources on the center gateway.
To center, or through the center to other satellites, to Internet and other VPN targets: The satellites can communicate with the center gateway, and also with other satellites, Internet hosts, and other VPN targets through the center gateway. This option is useful for branch offices that need to access resources on the center gateway, as well as on other branch offices, Internet hosts, and other VPN targets.
To center and to other satellites through center: The satellites can communicate with the center gateway, and also with other satellites through the center gateway. However, they cannot communicate with Internet hosts or other VPN targets. This option is useful for branch offices that need to access resources on the center gateway and on other branch offices, but not on Internet hosts or other VPN targets.
Therefore, the options A (To satellites through center only) and D (To center only) are not valid VPN routing options in a star community.
References: 1: Remote Access VPN R81.20 Administration Guide - Check Point Software, page 13 2: Gaia R81.20 Administration Guide - Check Point Software, page 1030
