Chapter 2 Advanced Routing for FortiOS 5.0 : Routing Information Protocol (RIP) : Simple RIP example : Configuring other networking devices
  
Configuring other networking devices
In this example there are two groups of other devices on the the network — internal devices, and the ISP.
The first is the internal network devices on the Sales, R&D, and Accounting networks. This includes simple static routers, computers, printers and other network devices. Once the FortiGate units are configured, the internal static routers need to be configured using the internal network IP addresses. Otherwise there should be no configuration required.
The second group of devices is the ISP. This consists of the RIP router the FortiGate routers 2 and 3 connect to. You need to contact your ISP and ensure they have your information for your network such as the IP addresses of the connecting RIP routers, what version of RIP your network supports, and what authentication (if any) is used.