The source of the routing information. This is one of: - an RPM, joined to DC-RTM on the Routing Protocol Input interface - 'static' for statically defined routes, defined in the static routes table with path type ATG_QC_PATH_STATIC - 'connected' for routes to local IP addresses and directly connected IP addresses and subnets, learned via the I3 interface, or defined in the static route table with path type ATG_QC_PATH_CONNECTED - 'all', meaning that this entry applies to routes from all RPMs and static routes, but not routes learnt via the I3 interface - 'all-incl-connected', meaning that this entry applies to routes from all RPMs, static routes, and routes learnt via the I3 interface.