Twitter co-founders Evan Williams and Biz Stone kicked off The Wall Street Journal's D: All Things Digital conference by stating their plans to keep the company independent. Indeed, both said they see themselves running the company five years from now.

"We're building Twitter and building an innovative company," Stone said. Williams added that they are modeling the company after Microsoft and Apple and are willing to navigate through tough times to build a long-term business.

The pair once again declined to announce any business model plans, but said they do endorse some options, like giving commercial account users extra features for a fee. The founders also said they'd like to set up a process to authenticate a company or person's identity for a fee.

"If you are a Dunkin' Donuts, you have a brand to protect and want to make sure no one else is pretending to be Dunkin' Donuts," Williams said.

As for banner ads, Williams said, "it's probably the least interesting thing we can do, but I wouldn't be offended if I was a user of Twitter and I saw banner advertising on the site, like you see banner advertising everywhere."