1. A system on chip (SoC) comprising: a semiconductor die comprising: at least one first processor and a first agent, the at least one first processor and the first agent associated with a first root space value to define a first root space; at least one second processor and a second agent, the at least one second processor and the second agent associated with a second root space value to define a second root space; a shared fabric to couple to the at least one first processor, the first agent, the at least one second processor and the second agent, the shared fabric to receive a transaction from a source agent and route the transaction to the first root space or the second root space based at least in part on a root space value in a root space field included in the transaction; and a host bridge comprising a first logical host bridge associated with the first root space and a second logical host bridge associated with the second root space, the host bridge further comprising a bridge to send a second transaction via a sideband interconnect, the bridge to insert into the second transaction a security field comprising the first root space value.