Computerworld

How one cash-strapped school district improved application performance

Podcasting and videoconferencing now possible across saturated links thanks to WAN acceleration

Education demands so much more than a notebook and pen these days.

Students rely on the Internet for research, teachers keep track of grades online, and administrators use internal networks to manage documents and enhance collaboration. Unfortunately, providing these tools requires a hefty investment in bandwidth, and many school districts aren't flush with cash.

The North Vancouver School District (NVSD) in British Columbia, Canada, is one such district whose goals threatened to overwhelm its means. About a year ago, with heavy use already straining the district's WAN, officials wanted to implement such programs as digitally linked scholastic records, podcasting and videoconferencing -- all of which would stress the network further.

"The network coming into schools was intended primarily for student use," says Stephen Lamb, director of information and communication technology at NVSD. "When we start running business applications across the same pipe, it becomes a difficult balancing act of what's going to take priority," he says.

NVSD achieved that balance using WAN-acceleration devices from Silver Peak Systems. First, however, the district in August explored -- and ruled out -- network expansion, says Bryan Swan, NVSD's IT infrastructure manager.

The dreaded bandwidth boost

The IT executives had a couple of reasons to consider a boost in bandwidth. First were the district's problems with application performance. For example, delays in such programs as BCeSIS -- the provincial government's Java-based Web application used for student management and grade reporting -- were becoming unacceptable. Second, the district was consolidating its network into a central data center to improve connectivity and data recovery. With 19,000 users on a variety of lines -- seven with a 10Mbps capacity, two with a 100Mbps capacity and 30 DSLs or T1s -- the IT department realized that buying more bandwidth for the network would be prohibitively expensive. Upgrading bandwidth at every school would have cost about US$400,000 initially, and annual upkeep was projected to cost about US$220,000.

The district also had to work with British Columbia's Provincial Learning Network, which allots a fixed amount of bandwidth to a district. PLNet officials have said they want to provide better connections, but as of last summer, Swan says they had offered no concrete indication as to when or how those improvements would occur.

"We had a need to provide a better WAN experience on a more immediate and definite timeline, so that is why we started investigating WAN-optimization products," Swan says. NVSD officials considered software from three companies besides Silver Peak -- Blue Coat Systems, Cisco and Riverbed Technology -- submitting the products to a variety of tests. Only Riverbed and Silver Peak made it through one key benchmark: that file transfers across the network take no more than 20 per cent longer to accomplish than transfers on a LAN.

The next step was to test the finalists on the FirstClass e-mail program-an organizational suite popular among educators-and it was there that Silver Peak stood out, showing a 75 per cent performance improvement.

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In all, Silver Peak's products proved easier to use with a wider range of applications, Swan says. Silver Peak takes an "application-agnostic approach" in its NX Series appliances, meaning that acceleration takes place at the IP layer. So, for example, Silver Peak can provide deduplication for streaming video, even though it runs on User Datagram Protocol rather than TCP, says Jeff Aaron, Silver Peak's director of product marketing. Considering the NVSD's strong interest in video, this capability made Silver Peak the way to go, Swan says.

The district plans to use 39 Silver Peak WAN-acceleration devices: two NX-7500s, one at the school-board office and one at the data-replication site; and an NX-3500s at each of the district's 37 schools. The district can't disclose the project budget, but notes that the cost was "significantly less" than a bandwidth expansion would have been, Lamb says. Should the district eventually add bandwidth, Silver Peak's WAN accelerators would further improve performance, he says.

Tested performance improvements

Application performance improved immediately after installation, the IT executives say. The district used a script file to open, save and close documents across a LAN, and compared those results with the average times of three tests that were run across the accelerated WAN. Tests on a LAN showed that a 2MB DOC file took about 5.33 seconds to save compared with an average time of 2.06 seconds on the WAN. Out of 18 tested files, only five performed slower than LAN speeds across the accelerated WAN.

"Overall, it's offsetting close to three-quarters of traffic off the network. We're effectively getting four times the size of the pipes that we have," Swan says, adding that such services as BCeSIS, which had been experiencing connection saturation, have been running faster.

Though the NVSD is almost finished with the installation, it is too early to say whether the district has seen a return on its financial investment, Lamb says. However, he emphasizes that looking at results from an expense perspective belies the district's mission. "We see student achievement as our return on investment, not increasing profit," he says. "We're really looking at anywhere on campus having access . . . and hopefully that transfers into greater student success."

Green, a Chicago-based freelance writer, can be reached at kent.green@gmail.com.