FierceTelecom: Wholesale Ethernet is also gaining a lot of attention as a sound mode for wireless backhaul. What are you seeing there in terms of new opportunities?
Stehlin: There are two groups of customers in the wholesale world. One is the LEC that is wholesaling to any wireless provider for years. Service providers such as CenturyLink or Windstream probably average between 2 ½ to 3 ½ wireless carriers per cell site. Their value is their ability to offer services to a wide range of customers that need connectivity.
The second group is the more focused regional mobile backhaul-focused operator. That's kind of like a CLEC for wireless backhaul that also wants to win that first customer, but then wants to branch out to other people that need connectivity.
The third is you might have Verizon or AT&T that is a LEC that wants to serve a lot of their customers out to that tower, but are primarily driven by their sister company or the wireless arm. In that regard we see LTE as being a big driver here. We're seeing AT&T and Verizon putting a big push on making sure they have the backhaul needed. They probably have half of their network covered with their own footprint and the other half going out to partners. In some cases it's a LEC and in some cases it's one of these wholesale CLECs, which could be everything from TowerCloud to Comcast. Those guys are getting into sites where there's 100 Mbps per wireless carrier per tower. Then, there's a legacy application where a non-affiliated wireless carrier like a T-Mobile that does not want to buy from a competitor but rather from a third party for their legacy 2G and 3G services.
There's this mix of "give me legacy traffic cheaper or give me brand new 100 Mbps connectivity and scale me to 300 Mbps." When you add it all together, what we're seeing is the guys that want to go to a big footprint at a tower need to bring a Gigabit of bandwidth out to the tower and need to be able to provide pseudowire. It's a combination of maybe 20 or so T1 equivalents out to a tower to handle multi-carrier pseudowires. Then it is three or four wireless carriers' worth of LTE bandwidth that could be a couple 100 Mbps each so you need a Gigabit.
FierceTelecom: To better target the wireless backhaul space's need for network synchronization, Overture late last year introduced the UTS 4000 and UTX 8500. What advantages does Overture's approach have over other synch sources?
Stehlin: It is not easy to get tight jitter specs out there. People don't want their voice to be any worse than it is today. It is similar to what's going on in the business side where SONET and PDH is the standard. From a class of service it has to be that good or better.
On the synchronization side, 1588 v.2 is really a standard that's becoming table stakes and you have to have that integrated into your platform. When you're designing these platforms, you have to have a programmable design that allows you to add these new features as these new requirements come up. Although we now know about 1588, there will be an added amount of new feature sets that will need to be supported. For example, carriers are working on External-Network to Network Interface (E-NNI), which enables carriers to hand off from one network to another. That will require the ability to look into that box and see where the issues are on both networks. You have to design a box that gives you that flexibility. Since commercial silicon won't get the job done for a number of years, you have to do it through some type of programmable device. Then you need to have the ability to put in capabilities to handle new needs as they crop up every six months or so.
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