How Fast Is Fast Enough?
10/15/2007 By: Karen Greenwood Henke
from Technology & Learning
The question of adequate bandwidth is increasingly the issue of the day.
Just how much bandwidth does the average student in the United States have access to today, and how much will he or she need in the future? That depends…is the answer from district CTOs, state technology directors, industry experts, and classroom teachers.
The National Center for Education Statistics reports that 97 percent of U.S. public schools with access to the Internet used broadband connections in 2005. But broadband encompasses a broad range of bandwidth. As capacity gets divided among more students using increasingly demanding data, voice, and multimedia applications, every student's service degrades.
The Networking Basics
Whether a student has the ability to watch an undersea video from the JASON Project or to create a report on earthquakes using U.S. Geological Survey maps depends on the speed, availability, and reliability of each part of the pipeline, including:
- The speed and quality of the device used for access. A computer, laptop, or handheld device requires memory, graphics ability, and a 100 megabit per second (Mbps) or better connection for most of today's Web browsing.
- The capacity of the internal school network, or local area network, which includes all instructional computers, administrative connections, and may include servers.
- The capacity of the line from the school to the district, the wide area network, where many students and teachers may be connecting to testing servers, student information systems, content management systems, and other large network applications.
- The capacity of the connection from the district office to the Internet or another service provider. Internet service contracts should guarantee a bandwidth level such as 1.5 Mbps T-1 services and should not split T-1 lines between multiple customers.
At each of these junctures, the more users who tap into the pipeline and the more demanding their applications, the less capacity available to everyone. A T-1 line with 1.5 Mbps may work just fine for a school of 500 students with a 5-to-1 student to computer ratio, but quickly taps out at a high school with 1,500 students and a one-to-one laptop initiative.
On testing day, when all students log in to a bandwidth-intensive testing site, an otherwise functioning network may reach capacity. Test sessions may time out before recording answers, or response time may be slow, both crucial factors in timed tests.
Pressure from the Students
Students feel the crunch when they compare Internet access at home to school. A 2005 study by Grunwald Associates, a market research firm specializing in Kâ€“12 education, found that of students who had only dial-up access at home, 35 percent still felt that connection was faster than the broadband they had at school, and 27 percent ranked access about the same.
"Schools are going to have to adjust to the new reality of how kids use digital media," says Peter Grunwald, president of the Maryland-based firm. "Not only are they heavier and heavier users, they are becoming producers of media through social networking and multimedia. Schools have to accommodate that to engage kids."
What does this mean for the classroom? "It's like not having enough books or enough chalk," says Edwin Wargo, a teacher and technology coordinator at Quarter Mile Lane Elementary School in Bridgeton, New Jersey. He is enthusiastic about the potential of technology to help students learn 21stcentury skills and compete in the global marketplace. But slow access hampers teaching and learning.
The Tipping Point
Even schools that can accommodate all of their network traffic today may be on the tipping point tomorrow. One more classroom application, a video conference, a learning game simulation, or more access points could each top out the network capacity, causing dropped connections, timed-out sessions, and lost data. Everyone agrees on one thing: if the bandwidth exists, students and teachers will use it.
For some, bandwidth is crucial. According to Tom Rolfes, education IT manager, Nebraska State Government Office of the CIO, the Nebraska state legislature has invested heavily in upgrading statewide education networks because "our rural schools live and die by video distance learning.…We have massive course exchange between schools and community colleges.…It's the next best thing to a highly qualified teacher in a face-to-face environment."
Previously, the 92 districts in the northeast region of the state shared 40 Mbps of access, giving each school about 640 kilobits per second (Kbps). An IP network upgrade, switching from T-1 WAN transport between schools to a regional Metropolitan Optical Ethernet Cloud now delivers a full 40 Mbps (26 T-1s) of transport to every district. By tripling the shared Internet access to 120 Mbps, or about 1.3 Mbps to each school, and improving transport speed, the districts can now accommodate all of their administrative and lab traffic, and run full 512 Kbps point-to-point videoconferences to support distance-learning courses. And the schools' budget line item for connectivity remained essentially the same.
One District's Journey
Northern California's Santa Clara Unified School District helped launch the effort to network schools in the very first NetDay volunteer wiring event back in March 1996. "Every teacher has e-mail and we encourage them to use Internet research in classrooms and computer labs," says then Business Manager Roger Barnes, now spokesman for the SCUSD. But as use increased, access slowed. "Three to four teachers at one school couldn't download videos at the same time. In the morning when everyone checked e-mail, it couldn't run at the speeds that they wanted."
Prompted by this overload, the district recently received bond funding for a 10-year school improvement plan and upgraded its LANs with fiber to the desktop. It built its own dark fiber transport network from schools to the district office, dropping leased lines. According to Barnes, owning your own network keeps costs under control and lets the district control capacity as well. The district had to give up E-rate funding to switch to its own network, but it calculated that the cost of the network over 10 years will be less than the leased line cost even with E-rate discounts.
Only Part of the Puzzle
Dennis Fazio, director of Technical Services for TIES, an education technology collaborative of 38 Minnesota school districts, warns that bandwidth is only about "5 percent of the solution."
"Technology makes great improvements in learning possible," says Fazio. "But a whole pile of things have to be lined up in addition to adequate bandwidth, including: enough computers; software that is easy to use; teachers that understand what they are doing; timely technical intervention and server and backroom equipment; a maintenance and turnover budget; and curriculum advisors and experts to help teachers be creative using the technology."
Technology coordinator Edwin Wargo agrees, but urges attention to bandwidth. Without adequate access, he cannot get the teachers he trains to see the potential for their classrooms. While leading a workshop on wikis for elementary school teachers, he agonized over a slow connection. "I got that bead of sweat on my forehead," says Wargo. "They were thinking, I can't do this in front of a room full of second graders, getting restless waiting for something to download. They don't realize it is the network, not the application."
A Better Way to Measure
To calculate school connectivity more accurately, in the America's Digital Schools 2006 Report, Tom Greaves, of the Greaves Group, and Jeanne Hayes, of the Hayes Connection, divided the total number of students by the bandwidth reported by district IT professionals. "Our viewpoint is from the student," says Greaves. "If the student only gets 1/1000th Mbps, it's safe to say the Internet is having no impact."
The ADS national survey of school districts found that current external bandwidth to the Internet averages 2.90 Kbps per student. Districts project expanding to support 9.57 Kbps per student by 2011, but calculations by Greaves and Hayes suggest that even this expansion will fall far short of the actual need, approximately 40 Kbps per student.
If costs remain the same and E-rate funding stays capped at $2.25 billion per year, districts may face rapidly escalating costs for additional bandwidth. "In West Virginia, an $800 T-1 line costs the district $300 [with their E-rate discount]," says Greaves. "A second T-1 line will be full price at $800."
So how much is enough for your district? That depends, according to the experts. What kinds of applications will students use? How integrated will data access and systems be to administration and student testing? Will data, voice, and multimedia applications be hosted inside the firewall at the district or school site, or do users need daily Internet access to perform tasks? Some tips for calculating:
Check your connection using a simple online bandwidth calculation meter such as the CNET Bandwidth Meter. Contact your ISP if you find a slower connection then expected.
Using a more sophisticated network reporting tool, track bandwidth needs over time to base calculations on maximum capacity needs. These reports show when peak times occur and how the bandwidth is being used.
Calculate the Kbps per student rather than per school site and distribute bandwidth more effectively between school sites with different needs. What goes into the calculation? Survey students, teachers, parents, and community members to find out what applications they use and expect to use for teaching.
Build in as much capacity as you can afford. Choose Category 6 copper or fiber optics to wire schools rather than Category 5. Some communities have combined educational and government services, sharing a metropolitan access network to defray costs and maximize bandwidth capacity.
Back to the Future
On the first NetDay, back in 1996, I helped punch down wire in the Santa Clara Unified School District. No one was sure how the networks would be used or what value they would have, but thousands of volunteers felt compelled to connect classrooms to the Internet, giving teachers and students the opportunity to figure it out. Today, we recognize that connection as a lifeline to the global information and collaboration essential to learning in the 21st century. Let's ensure our students are provided with the capacity to harness the Net-based tools they need.
Karen Greenwood Henke is founder of Nimble Press. Karen tracks technology and funding for schools at blog.grantwrangler.com.
T-3/DS3 dedicated digital transmission of data and voice at the speed of 45 MB per second; composed of 672 channels.
Fractional T-3 one or more channels of a T-3/DS3 line; used for data and voice transmission at the speed of less than 45 MB per second.
T-1/DS1 dedicated digital transmission of data and voice at the speed of 1.5 MB per second; composed of 24 channels.
Fractional T-1 one or more channels of a T-1/DS1 line; used for data and voice transmission at the speed of less than 1.5 MB per second.
Cable modem dedicated transmission of data through cable TV wires at a speed of up to 2 MB per second.
DSL (Digital Subscriber Line) refers collectively to ADSL, SDSL, HDSL, and VDSL. DSLs have a dedicated digital transmission speed of up to 32 MB per second.