Blog network = Main platform for SEO, Which it consists of two types
1. white hat technique
2. Black hat technique..
So, it can be identified either blog network is black hat or white hat by how they use / maintain their network.
For example,
-- > if blogger follows Google guidelines to build links (real, natural, non spammy links, unique articles, etc..) on blog network, then it consider as white hat technique..
-- > If blogger just build backlinks by not considering any Google Updates ( unnatural, spammy, automated links, spun articles, etc..) on blog network, then it consider as blackhat technique..