• by David Goetzl  @dgoetzl, April 18, 2011

It continues to be an auspicious time in the cable network business with the ad market, if forecasts are to be believed. And ad spending is the most volatile aspect of the sector.

Less considered by some outsiders is the always-reliable growth in traditional affiliate fees. Plus, new revenue opportunities are dawning from TV Everywhere to rights for iPad carriage. "Found money" might be an appropriate description there, since the investments -- producing content for the exploitation -- have already been made.

IPG's MagnaGlobal newly predicts ad dollars for national cable networks will grow by nearly 11% this year. That's just about in line with an 11%-plus forecast last week for cable's total haul in the coming upfront.

Traditionally, cable networks have tried to sell advertisers on offering lower costs and more targeted options than broadcast networks. MagnaGlobal indicates those pitches will be well-received and help drive cable's growth.

How strong is cable? The predicted 10.8% increase compares to a 3.1% 2011 growth projection across all media. Also, network TV, where parent companies are indicating a strong scatter market, would be up 2.4%, according to MagnaGlobal.

Cable's 2011 growth would be on top of 12.4% last year, though that did come off a tough year before.

Last week, Miller + Tabak & Co. analyst David Joyce has projected cable networks would take in 11.5% growth in volume for the coming upfront (up to $9 billion).

On new revenue streams, Time Warner Cable said Fox Cable Networks and Discovery have given the go-ahead to allow their networks to be delivered live to TWC customers on iPads in their homes.

Fox and Discovery had asked TWC to remove their programming from the system. The angered cable operator obliged, even though it felt it had already acquired the rights. But last week, a deal was reached -- likely including some sort of carrot for the two cable groups, if not cash.

TWC is in litigation with Viacom in the matter.

Separately, MagnaGlobal forecasts national digital advertising to grow 18.7% in 2011. Online video and mobile should be propellers, also offering a potential upside for cable.

The networks - and the Big Four broadcasters - should be able to grab a bulk of online video dollars, with their top-notch content and ability to use their on-air reach to drive viewers online and to less-developed mobile outlets.

Somewhat surprisingly, MagnaGlobal said "direct media," which includes paid search and direct mail, looks to have a bumpy 2011, projecting only 0.8% growth. MagnaGlobal said growth should accelerate, however, going forward as smaller and medium-size businesses participate more.

Yet, that un-rosy projection does not include direct-response TV, where cable networks can always turn to for some juice in a dry period.