1. A computer-implemented method for updating network security policy rules when network resources are provisioned in a service landscape instance, the method comprising: categorizing pre-existing network resources in a service landscape instance based on a service landscape model; responsive to provisioning a new network resource for the service landscape instance, automatically generating one or more security policy rules for the new network resource, and wherein associating the new network resource with a group name corresponding to a collection of the pre-existing network resources; and updating security policy rules of the pre-existing network resources in the service landscape instance, wherein the updated security policy rules describe which pre-existing network resources are permitted to communicate directly with the new network resource as well as security requirements for connectivity so as to include the new network resource as a remote resource based on the service landscape model, wherein each of the new network resource and the pre-existing resources comprises a software application residing on a computing device.