2Km is a prety short distance for mose of the stock 802.11 wireless geat, depending on what you budget is i could provide you with the whole solution including antennas

A couple of the guys have managed to use my antennas to do a 10km shoot using standard gear with no additional amps.

The way i would do it is to set up an outdoor Access Point on your work network with ethernet going down to connect it in to the network. the AP would be connected to a sloted waveguide in vertical mode so as to reduce the noise and increase the security.

at home you would have much the same setup except it would be in client mode. Prety simple as long as you have LINE OF SIGHT!

Regards
Andrew