Cox cable is beginning to charge Internet users an extra $15 a month for a service that reduces lag in online gaming.

Cox's new offer sparked concerns that the ISP is violating net neutrality principles. But the service wouldn't have violated net neutrality rules even if they hadn't been repealed, because Cox is merely reselling a third-party service and not making any changes to its broadband network.

Dubbed "Cox Elite Gamer," the service is a Cox-branded version of Wtfast, which can alternatively be purchased directly from Wtfast and used with other ISPs. Cox says the service "routes your game activity through a dedicated gaming network to provide a reduced latency path between your computer and the game servers of select online games."

But the service's limitations help demonstrate why it isn't a net neutrality issue. It only works on Windows computers, and only then when you install an application that connects to the special routing service, so online gamers who prefer consoles instead of PCs have no reason to buy it. "The service will not operate with game consoles or Macintosh operating systems," Cox says.

If Cox was implementing prioritization at the network level, it wouldn't be limited to Windows.

"This service does not increase the speed of any traffic, nor prioritize gaming traffic ahead of other traffic on our network," a Cox spokesperson told Ars. "Cox Elite Gamer solves a problem with deficiencies in the public Internet, not our network. No customer's experience is degraded as a result of any customers purchasing Cox Elite Gamer service as an add-on to their Internet service... the Cox Elite Gamer service selects an optimized Internet path with each gaming session initiated by the customers."

Cox's advertising claims the service results in 34 percent less lag, 55 percent fewer ping spikes, and 45 percent less jitter.

Cox Elite Gamer debuted this week in a trial run in Phoenix that will last for about three months. Cox will then decide whether to expand the service to other parts of its territory. "Following the trial period, we will evaluate the results and determine next steps," Cox said.

Cox is only making the service available to customers who subscribe to download speeds of 100Mbps or higher. Cox has about 5 million broadband subscribers in 18 states.

Wtfast declined to comment on its partnership with Cox when contacted by Ars.

Wtfast offers mixed results

The biggest difference between buying the service from Cox or Wtfast directly seems to be price. Cox's $14.99-per-month price includes simultaneous access for two PC users. But it appears to require a two-year agreement, and the price rises to $20 a month after the promotional rate expires. Cox sells additional licenses for $4.99 a month each, up to a total of five simultaneous gaming sessions.

Wtfast's direct pricing starts at $14.99 for usage on just one computer, but that's month-to-month pricing with no long-term commitment. A license for two computers is $28.48 a month. Wtfast offers discounted rates if you sign up for three months, six months, or 12 months of service. Twelve months on one computer costs $149.90, for example.

Is it worth it? IGN's Matt Elliott reviewed Wtfast in April 2017, testing several games and connections to servers in different regions. IGN found that Wtfast improved Overwatch latency when connecting to a game server in the Americas region from 301ms to 43ms, but in most other cases Wtfast had little to no effect. "Without Wtfast, my ping on Overwatch's Asia server was 249ms, and it dropped to only 202ms when I used WTFast and manually selected the 'East Asia (Choose Best)' option," Elliott wrote. With League of Legends, Elliott found average latency of 43ms without Wtfast and a nearly identical result of 44ms with Wtfast.

"Wtfast was able to impressively improve our ping in some tests, but had no impact in others," IGN wrote. "If you have a slow ping of 150ms or more on your favorite online game or often want to connect to international game servers, or just want to get any edge you can, it may be worthwhile to give WTFast a try."