2:54 PM ET

The NBA is trying to implement an upper salary limit in its negotiations with the National Basketball Players Association, a change that has been met with resistance.

The NBA wants to replace the luxury tax with a hard limit that teams can't exceed, sources said.

Sources said that the NBPA was against the league's proposal to the point that it was a non-starter in talks.

The early part of the negotiations can be used to float wish lists, and that could be what's happening with the NBA's proposal.

There is a December 15 deadline for the NBA and NBPA to give notice on opting out of the current collective bargaining agreement. The seven-yearCBA ends after the 24th of February.

According to sources, the NBA believes that the current system doesn't provide enough playing field to make more teams competitive, and that the spending disparity of top teams has made the imbalance unsustainable. The idea of a more competitive league delivering higher revenues and higher salaries is being pitched to the union by the league.

There is skepticism among smaller NBA marketplaces who worry that an upper spending limit would fail to create the competitive parity that the league is hoping to achieve, instead causing well-constructed smaller market teams to have to break up core of contention talent.

The NBA's Labor Relations Committee, including Charlotte owner Michael Jordan and Golden State owner Joe Lacob, has held several meetings with the union.

The system now allows teams to re-sign their own players and increase their salary in free agency if they exceed the salary cap. The NBA's proposed system change would end luxury tax payments that are shared with many smaller market teams, forcing the league to find a new mechanism for revenue sharing.

Twenty of NBA 30 teams are below the luxury tax threshold, with 10 teams projected to pay a league-record $697 million in luxury tax penalties. Sixty percent of that was shared by the Golden State Warriors, the Clippers and the Nets.

The three teams made up 73 percent of the luxury tax penalties.

Sources said that the league's top priorities were among the other top ones.

The league's media rights deals can be more valuable if mechanisms are found to encourage top players to participate in more regular season games.

A "smoothing" plan to add in the windfall of revenue in the league's upcoming media deal, which would avoid a repeat of the cap spike in 2016 that disproportionally rewarded one class of free agents, is being worked on.

To end the "One-and-Done" early entry rule and allow high school players back into the NBA draft, the league wants a requirement that player agents can't pick teams with which they supply medical and physical information. There are no requirements for presence or participation in the draft combine.

There's always the chance that the deadline could be extended should the sides believe they're making progress, as discussions are expected to become more frequent between now and December 15.

Bobby Marks is an employee of the front office of the sports network.