your question about "Link Laundering": Link Laundering is a black hat seo: Link laundering is a lot like money laundering. You take low quality, crappy links and turn them into high quality, relevant, one way anchored links pointing to your main site. In reality, you're turning these low quality questionable links into high quality trusted links. Just like turning dirty money into crisp clean money!..
hackers target sites using older content management systems with known vulnerabilities; they take control of the site and insert dozens or hundreds of spammy links. http://searchengineland.com/link-laundering-the-growing-threat-that-tarnishes-white-hat-sites-90473
by just the term "laundering" - it's obviously against the legitimate method.. a big no-no if you're protecting your site's reputation
[h=2]Link Laundering is a blue hat SEO technique its helps to gathering more traffic to your website through this process..[/h]
Link laundering’ is the process of converting a crappy website into a high quality site by linking it up to high quality sites. Once that ‘crappy’ website gains some credibility, you link it to your website selling harmful products in order to improve the ranking and traffic to it.