Sub-affiliate
A sub-affiliate is an affiliate invited by another affiliate, who then earns a percentage of the sub-affiliate's earnings.
A sub-affiliate is an affiliate who joined through another affiliate's invite link. The inviter earns a percentage of what the sub-affiliate earns, usually paid by the network.
Why networks use it
Affiliates know other affiliates. Sub-affiliate programs turn your partners into recruiters and reward them for growing the network.
One level or many
Most programs pay on one level only. Paying on several levels makes the program harder to explain and can look like a pyramid scheme.
In Rastro
One level, paid by the network, with reversals handled automatically. See Sub-affiliates.