Operators need backhaul to meet subscribers’ demands. The trick is to structure it in such a way as to meet demands without overbuilding or spending too much.
One way to summarize the current and future state of backhaul may be to reference a recent movie release: It’s Complicated.
In fact, some analysts say operators face a monumental task. New smartphones are increasing consumers’ appetite for data, which means more demand for backhaul. In some cases, operators might need to strike deals with cable companies or wireline arms of their competitors, and while that’s nothing new, it plays a role. If an operator wants to site its own facilities for backhaul, it may need the blessing of local zoning authorities. Plus, the industry is moving from a time domain multiplexed (TDM)-based platform to Ethernet, and radios must be capable of both in the interim.
“It’s a completely different way of looking at the market than the operators have been used to,” says Emmy Johnson, founder and principal analyst at Sky Light Research. “The traffic going over the network is different from standard voice traffic, so they have to architect the network to accommodate these peaks and do it as efficiently as possible so they aren’t overbuilding and overspending … It’s so new it’s hard to understand the user patterns on a broad level. We’re really at the beginning of it.”

With voice as the primary traffic component, an operator could meet its backhaul requirements with a couple of T1s per base station. But with more emphasis on data, the requirements are changing. In-Stat says 90,000 Gbps of capacity in the last mile of the backhaul network will be needed by the end of 2013 to support the world’s cellular and WiMAX networks. In fact, In-Stat predicts the need for backhaul capacity will grow three-fold between 2009 and 2013. Between now and 2015 or 2016, backhaul demand will increase at least 10-fold on average, says principal In-Stat analyst Allen Nogee.
“It will certainly only get worse as LTE comes out and faster systems come out,” Nogee says. Operators don’t necessarily have to have it all in place when LTE is first introduced and gaining users, but the backhaul that operators need for 4G will increase as streaming video and other apps pick up. Operators may adjust pricing plans accordingly so heavy users pay at least part of the backhaul load.
LONG TIME COMING
The industry has known for a long time that backhaul requirements would increase as operators move to 4G technologies. So why are operators still grappling with the backhaul part of the equation, sometimes even in 3G networks?
In an FCC filing late last year, T-Mobile USA explained that as it deployed its 3G network, it was trying to develop alternative sources to backhaul supply, including wireless. One major obstacle it found, however, was a delay associated with siting such facilities. To meet growing demand for backhaul, third-party suppliers and mobile carriers need to collocate or install new facilities, such as microwave dishes, transmitters and towers, and in many cases, it has to obtain authorization from state and local governments, the carrier said in its filing.
Part of delays in securing backhaul solutions may have to do with the size of the transformation in network architecture. Moving from TDM to Ethernet is not the kind of transformation that can happen overnight. “It does take time. The operators are all moving in that direction,” some faster than others, says Wendy Cartee, vice president of marketing in the edge and aggregation business unit of Juniper Networks. Ethernet was invented as a wireline technology, not for wireless backhaul, so as Ethernet gets deployed in the mobile infrastructure, enhancements are made to make it more “mobile friendly,” she says.
A LOT OF WORK, MONEY
“We’re all moving rapidly,” says Marty Snyder, CEO of Communication Infrastructure Corporation (CIC). The work starts at the core and eventually gets to the edge, but along the way, a lot of equipment must be replaced. “There’s a lot of money involved here,” he says, and carriers that just spent the last 20 years installing equipment do not want to replace it.
Aside from Clearwire, which sees microwave as the preferred method, many operators identify fiber as the ideal choice for backhaul. Weather can affect the performance of microwave links, and “fiber is the gold standard, if you will,” says Nogee.
Even those operators that prefer fiber may need to consider microwave in areas where it makes more sense, but even with microwave, various flavors exist. “There’s no panacea, there’s no one technology that solves all the problems or half the problems,” Snyder says. “You have to look at all the links on a case-by-case basis.”
CIC also looks at what’s available from cable companies. “We exploit every fiber possibility there is. Nothing is off the table,” Snyder says, including municipal fiber.
Aurora Networks is one of those companies targeting cable operators with a standards-based solution that allows cable companies to compete for a share of the business. “Backhaul is a huge opportunity for cable,” says Shridhar Kulkarni, product manager, access network solutions at Aurora.
Cable operators aren’t the only ones getting in line to offer solutions. “It’s unprecedented,” Snyder says. CIC started doing backhaul in 1997 and was hard-pressed to find providers. “Now I’m sending out RFPs to 10 providers.”
Filed Under: Infrastructure