Cable networks have to work extra hard to establish their brands, unlike broadcast networks whose longevity and prominence make them difficult to miss.

Through creative advertising campaigns and noteworthy shows, cable networks such as TNT, FX, USA and lately AMC have established their identities with the public. We tend to know what we’ll be getting when we tune in to those channels: crafty escapism on USA, sophisticated storytelling on FX, mainstream procedurals on TNT and urbane, cinematic drama on AMC.

So why would an established cable network mess with a good thing?

For Sci Fi — which changes its name Tuesday to Syfy — it’s a matter of survival.

The old way of doing business — in which a network merely airs programs and collects ad dollars — won’t quite cut it in the multimedia future, said Sci Fi president Dave Howe in a recent interview.

And the name Sci Fi — which also applies to an entire genre of film, books and other forms of media — wasn’t something the network could trademark.

“Nothing gets greenlit unless we believe the business model is much more than linear, live viewing,” Howe said, citing DVD movies, video games, Webisodes, Web sites and iPhone apps as just a few of the multimedia ventures the network sees as vital to its future. But Sci Fi wanted to brand those kinds of ventures with a name it could own and trademark.

“When people understand the rationale, they do get it,” Howe added. “You can’t have a brand called ‘Sport’ or ‘Drama’ or ‘News.’ It’s just not a brand name.”

Certainly, awareness of Sci Fi, which was launched in 1992, had grown in recent years, especially during the era of the award-winning “Battlestar Galactica,” which ended its run in March. During Howe’s tenure — he’s been at Sci Fi for eight years — the network went from exporting shows to a few other countries to shipping programming to more than 50 territories.

As the network expanded worldwide and into multimedia realms, executives wanted a more distinctive name, but finding a name that would not only work for the network but be available legally and obtainable in the online realm (the network’s new site will be syfy .com ) took two years.

“The issue that we’ve always had with Sci Fi is that it only communicates three things: Space, aliens and the future,” Howe said.

“That’s the default perception, and that’s a barrier to entry for people who we know like (reality fare such as) ‘Ghost Hunters’ and ‘Destination Truth’” as well as “Eureka,” which returns July 10, and the sprightly and amusing “Warehouse 13,” which premieres Tuesday.

There was a fair amount of mockery, especially in the online realm, when the name change was announced in March, but Howe said that compared to the cancellation of “Stargate Atlantis,” which overwhelmed his e-mail inbox for months, he’s only gotten a couple of dozen snarky e-mails about the Syfy switch.

“We expected fans not to like it. The reaction from fans is always the same default reaction — it’s that we’re going to abandon the genre,” Howe said. “This isn’t what that’s about.”