Eric, the Chinese version would be Elic ;-)

There is a bus service from the airport to Belfast and from Belfast to Portaferry.
(but I found: http://www.translink.co.uk/keytables_airbus.asp and http://www.translink.co.uk/present/ULB_9A10_O.asp by simply feeding "Belfast International Bus" / "Belfast Portaferry Bus" into Google)

Taxi from airport to Portaferry is 48 Pounds - a big lot of money if you are going alone - I don't know how much the airport bus costs and what the taxi would cost from Belfast, but I guess it might be less ...

It says 6 Pounds for the bus from Airport to Belfast (9 Pounds if you by a return ticket).
Belfast - Portaferry seems to be 4.90 Pounds (8.90 for the return ticket)