Methods for transmitting information from sources (7) via first network units (1) and networks (8) and second network units (2) to destinations (9) and using service identifiers such as service virtual local area network identifiers for routing the information through the networks (8) get a reduced complexity by making the service identifiers dependent on destination properties such as destination addresses and by making the service identifiers independent from source properties such as source addresses or customer identifiers. Network units (1,2) comprising customer parts (5) with customer access ports (10) and customer interface ports (11-13) and comprising service parts (6) with service interface ports (21-23) coupled to the customer interface ports (11-13) and service network ports (20) coupled to the service interface ports (21-23) and comprising taggers (62) are provided with detectors (52) for detecting destination properties in the information and selectors (53) for selecting the service identifies in response to detections of the destination properties.