Abstract: A computer system includes an apparatus which enables transactions directed to a particular target device such as one situated inside a bridge to be shunted directly to the device without requiring that the transaction actually proceed to the device through a bus on which the device is located. However, the transaction may, in fact, also be run on the bus on which the device is located, the ID select for the target device may be masked. In this way, it is possible to run transactions to a particularly critical device even when the bus on which it is located is, for one reason or another, not operating.