Introduction to Routing

Routing is the process of forwarding packets from one network to the destination address in another network. Router, a packet forwarding device between two networks, is designed to transmit packets based on the various routes stored in routing tables. Each route is known as a routing entry.

The security appliance is designed with Layer 3 routing. This function allows you to configure routing options and forward various packets via VRouter. System ships with a default VRouter trust-vr, and also supports multiple VRouters (multi-VR).

System supports destination routing, ISP routing, Source-Based Routing (SBR), Source-Interface-Based Routing (SIBR), Policy-Based Routing (PBR), dynamic routing (including RIP, OSPF and BGP), Equal Cost MultiPath Routing (ECMP) and Static Multicast-routing.

• Destination routing: A manually-configured route which determines the next routing hop according to the destination IP address.
• SBR: Source IP based route which selects router and forwards data according to the source IP address.
• SIBR: Source IP and ingress interface based route.
• ISP routing: A kind of route which determines the next hop based on different ISPs.
• PBR: A route which forwards data based on the source IP, destination IP address and service type.
• Dynamic routing: Selects routers and forwards data according to the dynamic routing table generated by dynamic routing protocols (RIP, OSPF or BGP).
• ECMP: Load balancing traffic destined to the same IP address or segment in multiple routes with equal management distance.
• Static Multicast-routing: Manually-configured routing which broadcasts packets from a multicasting source to all the members within a group.

When forwarding the inbound packets, system selects a route in the following sequence: PBR -> SIBR -> SBR -> Destination routing -> ISP routing -> Dynamic routing.