MIAMI — As the cruise industry rushes to expand the availability of WiFi for passengers, Disney Cruise Line has broken from the pack on the model it uses to charge for Internet usage on its ships, offering a system based on how many megabytes are used rather than on how much time is spent online.

The result is a system that costs less for services that don’t use much data, such as email, and more for bandwidth-hungry uses, such as streaming video.

The pay-by-the-minute model is the current standard at sea.

In practical terms, guests who only want to send or retrieve a few emails will pay very little, while those who want to use the Internet as an onboard entertainment system to stream movies or YouTube videos, for example, will pay more.

Disney is the first line to implement the Connect@Sea system developed by MTN Communications. Beyond enabling the cruise line to better match a user’s needs to the price charged, MTN said the data allotment system makes more efficient use of bandwidth. As a result, speeds for all users should increase.

“We think it’s going to be the wave of the future,” said Brent Horwitz, MTN’s senior vice president of cruise and ferry services.

Cruise lines have been pushing suppliers of Internet connectivity to come up with faster and more creative ways to provide access as demand soars and guests’ expectations of seamless, ubiquitous connections grow.

Lines are especially eager to foster social media use by guests, because postings by passengers on Facebook, Instagram and Twitter serve as user-generated marketing messages that are cost-efficient and perceived by the general public as highly credible.

But ships are limited by their dependence on expensive satellite telecommunications when they are out of range of land-based transmission infrastructures.

Disney began rolling out the service in early February on the Disney Magic and finished this month with the Disney Fantasy.

“The data-based pricing is available onboard all four ships,” said Disney Cruise Line spokeswoman Lauren Falcone.

Charges start at 25 cents per megabyte in a pay-as-you-go option that Disney describes as “perfect for guests who are not sure how often they will be online.”

WiFi packages, however, offer passengers savings for buying their megabytes in bulk.

Disney said a medium package of 300 MB would be good for users who want to share vacation photos right away. It costs $39, or about 13 cents per MB, while the heavy-use package of 1 gigabyte costs $89, or 9 cents per MB.

Since many users don’t know how many megabytes their various applications take up, there is a browser-based graphic gauge that provides a readout of how much data has been transmitted on the account.

Previously, Disney had charged 75 cents a minute for pay-as-you-go service, a charge that is typical among cruise lines.

With time-based WiFi services, bulk packages on cruises of seven nights or less range from $27.50 for 50 minutes to $74 for 250 minutes. Packages with more minutes are available on cruises longer than seven nights.

MTN’s Horwitz said that with a data-allotment system, the speed of service will be “multiple-times higher” because it is a more efficient way to use the transmission system. In addition, MTN and other providers are perfecting just-in-time increases in bandwidth capacity that can be used to improve flexibility.

Another advantage of using data metering is that guests can remain logged on to their email for long periods, since there are no per-minute charges. Users of the pay-as-you-go plan can set a predefined spending limit so they don’t inadvertently exceed their budget, according to Disney.

Horwitz said that by stimulating use while making pricing more flexible, MTN hopes data allotment will make Internet access both more profitable for the cruise line and more user-friendly for the guest.

With faster speeds, “the cruise passenger will have something more commensurate with the rest of the cruise vacation,” he said.