Abstract: An access unit (25) for configuring a first and second network-layer protocol for use over the point-to-point link and to facilitate communication between an Internet Service Provider (ISP) (20) and a data processing system (12) over the link. The data processing system (12) includes a first 28(1) and second protocol stack 28(2). The access unit (25) includes a multi-protocol (32) driver for routing a packet received from the ISP (20), a Wide Area Network (WAN) access driver (24) adapted to monitor an establishment of the link connection to capture a maximum receive unit, and a converter (23) adapted to receive a trigger from the WAN access driver (24), the trigger for indicating to the converter (23) to configure the second network-layer protocol on the link.