A method and apparatus for providing transaction services to one of a plurality of organizations where such transaction services are provided for servicing contacts with clients of the organization through an independently operated contact processing system having a communication connection with the organization through the Internet. The network processor maintains a schedule indicative of respective times at which a plurality of virtual channels are to be serviced. The compounds according to the invention are particularly suitable for controlling insects, arachnids and nematodes in agriculture and ectoparasites in veterinary medicine.