SpaceWire routers can implement group adaptive routing. When two or more output ports lead, either directly or indirectly, to the same destination, these output ports may be configured as a group. When a packet arrives at an input port for routing out of an output port that is busy, any other output port in the same group as the addressed output port may be used to forward the packet.

A routing table in a router that implements group adaptive routing is illustrated in Figure 54. Logical address 33 has two output ports assigned to it. When a packet with this logical address is received the router has the choice of routing the packet out of port 3 or port 4.

Routing Table with Group Adaptive Routing

Figure 54 Routing Table with Group Adaptive Routing