An affiliate marketing network is an intermediary service that is provided by a third party to facilitate affiliate programs between the affiliate merchants and the affiliates.
Generally an affiliate marketing network provides services such as affiliate tracking, reporting, database management, paperwork, legal documentation, payments to affiliates etc.
Major functions of an affiliate network
Maintaining databases of affiliates and affiliate merchants to facilitate both
Carrying out affiliate program promotions of various affiliate schemes
Maintaining the latest affiliate tracking software and carrying out affiliate tracking activities
Taking care of all legal and other documentation for the affiliate merchants
Paying out the affiliates on a regular basis based on commission schemes of individual affiliate merchants
Taking care of any disputes that arise between the affiliate merchants and the affiliates
An affiliate network carries out these functions based on fixed service fees that are charged to the affiliate merchants. Mostly the service fee includes the joining fees and there-after based on the number of transactions paid out. Most affiliate networks like commission junction carry out the entire commission schemes on their own; where as some networks like Linkshare offer the affiliate merchants complete control over their commissions.
Some well known affiliate networks are Commission Junction (cj.com), Linkshare (linkshare.com), Affiliate Fuel (affiliatefuel.com), Clickbank (clickbank.com) etc. In addition to acting as intermediaries affiliate networks also offer their own pay per sale (PPS), pay per lead (PPL), pay per action (PPA), and pay per click (PPC) affiliate programs for affiliate to promote on your web sites.