A device (107, 207) for routeing a unit of data in a network, the device comprising a processing means operable to: determine a destination address of the unit of data; assign the unit of data a forwarding label, FLo, based on the destination address of the unit of data; characterised in that the processing means is operable to select a routeing record from one or more routeing records by identifying one of the routeing records that comprises information that corresponds to the destination address of the unit of data, each of the one or more routeing records comprising a forwarding label, FLo, and additional information that corresponds to application information contained in the unit of data, the additional information comprising a reference to an application forwarding table; and in the event of the reference to the application forwarding table in the selected routeing record being empty, forward the unit of data over a path identified in the forwarding label, FLo, of the routeing record; in the event of the reference to the application forwarding table in the selected routeing record not being empty, forward the unit of data over a path identified in the referenced application forwarding table, wherein the device is configured to route a unit of data in a network for a plurality of application providers, and the device comprises a separate application forwarding table for each different application provider, wherein the device is arranged such that the application providers can alter the various labels contained in the application forwarding table maintained by the device, and the device is further arranged such that application providers can only alter application forwarding tables and labels that are associated with them. determine a destination address of the unit of data; assign the unit of data a forwarding label, FLo, based on the destination address of the unit of data; characterised in that the processing means is operable to select a routeing record from one or more routeing records by identifying one of the routeing records that comprises information that corresponds to the destination address of the unit of data, each of the one or more routeing records comprising a forwarding label, FLo, and additional information that corresponds to application information contained in the unit of data, the additional information comprising a reference to an application forwarding table; and in the event of the reference to the application forwarding table in the selected routeing record being empty, forward the unit of data over a path identified in the forwarding label, FLo, of the routeing record; in the event of the reference to the application forwarding table in the selected routeing record not being empty, forward the unit of data over a path identified in the referenced application forwarding table, wherein the device is configured to route a unit of data in a network for a plurality of application providers, and the device comprises a separate application forwarding table for each different application provider, wherein the device is arranged such that the application providers can alter the various labels contained in the application forwarding table maintained by the device, and the device is further arranged such that application providers can only alter application forwarding tables and labels that are associated with them.