Here are some of the players, where they stand and how they work.

As a result, the products that provide hosting or security services to these controversial sites have themselves become part of the story.

In particular, these forums rely on the products that keep them safe from large-scale web attacks, especially those known as "distributed denial of service" or DDoS attacks, which deliver an overload of information to servers, shutting the sites down. The sites are under constant threat of these attacks because of the controversial rhetoric hosted on them.

But 8chan and other similarly controversial sites have a very difficult time operating without the hosting infrastructure in place to support them.

Online forum 8chan is controversial because several people used it to espouse white supremacist views before allegedly committing mass shootings in El Paso, Texas; Poway, Calif. and Christchurch, New Zealand.

Cloudflare is one of the largest companies that provides DDoS protection services, and is reportedly preparing for an IPO later this year. The company has a full range of products, but the DDoS service is most relevant to 8chan's plight.

Cloudflare announced over the weekend it would no longer work with 8chan as a customer, meaning it would effectively end offering its protective capabilities against DDoS attacks. The 8chan site went down shortly after Cloudflare pulled its support, and said it expected "24-48 hours" of downtime in a tweet late Sunday.

"Cloudflare's mission is to help build a better Internet. At some level firing 8chan as a customer is easy. They are uniquely lawless and that lawlessness has contributed to multiple horrific tragedies. Enough is enough," CEO Matthew Prince said in a blog post on the company's website.

Prince also went on to say that creating these policies can be difficult, because tech companies have not yet worked out how to apply them consistently and fairly to all purveyors of inflammatory or inciteful speech.

"What's hard is defining the policy that we can enforce transparently and consistently going forward. We, and other technology companies like us that enable the great parts of the Internet, have an obligation to help propose solutions to deal with the parts we're not proud of. That's our obligation and we're committed to it," he said.

In its place, 8chan reportedly sought the services of a smaller DDoS mitigation service called BitMitigate, owned by web hosting company Epik, based in Sammamish, Wash.

Epik is known for working with websites connected white supremacy, like the neo-Nazi website Daily Stormer, after they were dropped from Cloudflare's service. The company said that, despite reports, Epik has not "made a definitive decision about whether to provide DDoS mitigation or Content Delivery services for [8Chan]," according to an Epik spokesperson, via email.

For a while, it appeared 8Chan was getting back online intermittently on Monday. Then, another tech company called Voxility, which rents hardware to Epik, discoutinued its service to Epik. This made it impossible for BitMitigate to reach 8chan, and effectively shut down 8chan again.

Voxility wrote in response that "We are all in the same team here! Thank you for the support and for the notes. The 3rd party hoster is blocked completely."

Voxility tweet

According to the Epik spokesperson, the question of whether to provide services to these websites is related to freedom of speech. The spokesperson also said the company's stance was that 8Chan was complying with legal requirements.

"Freedom of speech and expression are fundamental rights in a free society. We enter into a slippery slope when we start to limit speech that makes us uncomfortable. The censorship we've seen across major social media platforms as of late has created a vacuum. Our services fill the ever growing need for a neutral service provider that will not arbitrarily terminate accounts based on social or political pressure."