Chicago-based real-estate management company Equity Office ran all its voice and data traffic over an MPLS WAN, but when poor peak-time performance drew complaints from end users, it switched to technology that delivers more bandwidth at half the cost.
There's a tradeoff in that the company has to deal with more service providers than before, but the performance and savings make up for that, says Chavdar Momchev, Equity Office's director of voice-data communications. "I expect a return on investment in about 10 months," he says, and complaints about response times have disappeared in offices that have the new connections.
The new WAN is fashioned by blending DSL, cable, fiber and Ethernet over copper into a single logical network. When one link fails, remaining links pick up the slack under the direction of intelligent hardware from Talari Networks.
Once it is switched over, the new WAN will cost about half the $400,000 per year he was spending on the MPLS service, Momchev says. When he factors in the capital cost of the Talari boxes, he projects a 10-month return on investment.
Momchev's biggest fear was that it would degrade the quality of VoIP traffic running over the network, but there have been no problems even when one of the circuits feeding each office has failed. "We've been having outages, but there has been no impact on end users," he says.
Equity Office has a headquarters in Chicago and about 40 remote offices. Headquarters contains the main data center, with an active disaster-recovery data center in Madison, Wis. Each remote office is connected as a spoke to both headquarters and the backup data center as hubs. The data centers also act as hubs for the Cisco VoIP system.
Until the change to the Talari gear, each office was connected to a Verizon Business MPLS service by at least a T-1, with a few larger offices having two or three T-1s.
The MPLS service was put in about seven years ago, and shortly afterwards the company underwent server consolidation, pulling virtually all servers out of remote offices and centralizing them in the data center.
The only way the Equity Office could do that was by installing WAN optimization gear from Riverbed at all sites, effectively reducing WAN traffic enough so branch workers could get seemingly local performance from central data center servers. "They were the missing piece that made it possible," Momchev says.
Each office had DSL connections that offered Internet backup to the MPLS network, but when there were MPLS outages, the performance of the backup was poor, he says.
But in the mornings when employees were logging on for the day, traffic spiked so much that even with the Riverbed optimization performance dropped. Workers could wait a minute for a file to download. Since he was already optimizing the bandwidth, his only recourse was to buy more bandwidth, but the costs of bigger MPLS links were too high, he says.
So he looked at Elfiq, Ipanema and Talari, ruling out Elfiq because it couldn't support a hub-and-spoke architecture. He trialed Ipanema and Talari for six or seven months each. He says Ipanema's gear couldn't make per-packet decisions needed to keep up VoIP quality. "I have VoIP to take care of, so that was a deal breaker," he says.
He spent 2010 testing out Ipanema and Talari, and after choosing Talari has spent this year switching over sites from Verizon Business. That task is about two-thirds done and he expects to finish by year-end.
In setting up the new network, he has supplied each office with at least two diverse WAN connections from different providers that don't share local-loop infrastructure. That reduces the chances that both connections will die at the same time. Larger branches have up to four separate connections from separate providers.
That gives each office at least twice the bandwidth it had before, and in some cases triple, eliminating the bandwidth congestion suffered during the busiest times.
This arrangement increases the number of service providers from one - Verizon Business - to more than half a dozen, including ComCast, Time-Warner Telecom, XO, MegaPath and Covad. Providers give Equity Office an Ethernet handoff so he has no new customer-site hardware to manage, but he does have to manage the Talari gear.
That equipment sits on the LAN side of WAN providers' routers, aggregating the multiple connections. It is intelligent enough to choose the best route for each traffic type and reroute traffic if one link fails, he says.
Equity Office is still running the Riverbed WAN optimization appliances on the new WAN, making the most of the increased bandwidth.
He had relied on Verizon Business to manage the MPLS network, and since he doesn't have the staff to manage the new network in-house, he has hired Black Box Network Services for less than he was paying Verizon.
The new WAN has more than enough bandwidth to handle peak demand, and that works to boost users' faith in it, he says. "On average, during the day, peak load time is when people build their perspective of whether it's a vast vs. slow network," he says.
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