Add mobile advertising to the list of “hidden traffic” sources that are becoming a problem for carrier networks.

According to a report by comScore, Inc., mobile advertising spending is projected to reach $2.5 billion by 2014 in the U.S. And according to an infographic by Mashable, in-app ads account for around 5% of mobile ad spending, and this is expected to surpass $860 million in revenue by 2014.

While this growth is great news for the mobile advertising industry, it is troubling news for carriers already battling the overwhelming data traffic caused by unruly mobile apps.

As we’ve discussed previously, ad-based apps can generate a great deal of signaling on the wireless network, for example, one report showed an Android-based device playing Angry Birds with mobile advertising generated a whopping 2,422 signals in one hour of play!

Here at SEVEN we’ve been tracking this issue closely. Mobile advertising is the way to engage new customers and as industry experts have reported, it will only continue to flourish over the next few years.

However, our concern is that mobile advertising traffic is mostly unmanaged and unmonitored, until carriers find a way to work with mobile advertisers to reduce the signaling and bandwidth produced by these advertisements.

One way that we’re working to solve this problem is with our Open Channel traffic optimization solution, which eliminates unnecessary network requests and reduces the overall amount of chattiness created by apps on the network.

Stay tuned for more on how this growth market will affect the carrier network and ultimately the consumer experience.