Wireless Technology– What’s There For Your District?

7th Annual 2002 K-12 Networking ConferenceFebruary 26 - March 1, 2002Marriott Crystal Gateway, Crystal City, VALeadership for the Digital School: Implications, Opportunities and Challenges

Daryl Ann Boreldborel@houstonisd.orgAssistant Superintendent, Technology

Gary Teetergteeter@houstonisd.orgSupervisor, Special Projects

Houston Independent School DistrictHouston, Texas

REMEMBER WHEN … Students sat quietly in rows and worked by themselves with pencil and paper.

NOW … Students work in groups, use the Web to get the latest content, talk to experts online and in person, and learn from images, sound and text. In classrooms today learning is active and technology is well-integrated.

How We Got Here

In November 1998, 73% of the citizens of Houston approved a $678 Mschool facility bond package for repairs of 69 schools and construction of10 new schools.

Items for Discussion

Wireless Networking Overview Types of Wireless Networks Wireless Standards Security Issues

Key Components – WLAN Deployment Issues Advantages of Wireless Laptops Lessons Learned Areas to Monitor Questions and Responses

Wireless Networking Overview Background

Vast majority of LANs based on wired Ethernet

10 Mbps 10/100 Mbps Gigabit (1000 Mbps)

Wireless wasn’t accepted for 3 reasons Throughput (1 Mbps/2Mbps) Wireless adapters and access points too expensive First wireless products didn’t work well together

Wireless LAN (WLAN) is a LAN Natural extension of wired LAN and WAN networks Wireless doesn’t mean “Without Wires”

Types of Wireless Networks

1. Bluetooth- based on the short-range transmission of radio signals; a Wireless Personal Area Network (WPAN) which allows devices to achieve point-to-point connection forming a highly mobile network that moves as devices move.

2. IrDA (Infrared Direct Access) – uses infrared light pulses. Ex. Remote controls. Requires direct line of sight.

Spread Spectrum(designated by IEEE 802.11)

Direct-sequence Spread Spectrum (DSSS) – devices using DSSS communicate by splitting each byte of data into several parts and sending them concurrently on different frequencies. DSSS uses a lot of the available bandwidth, about 22 MHz.

Frequency-hopping Spread Spectrum (FHSS)- devices using FHSS send a short burst of data, shift frequencies (hop) and then send another short burst.

FHSS devices are less prone to interference than DSSS devices, but DSSS is capable of much greater speed than DHSS since these devices can send a lot more data at the same time.

Both are based on spread-spectrum radio waves in the 2.4GHz range

Types of Wireless Networks

3. HomeRF (Radio Frequency) and SWAP (Shared Wireless Access Protocol)- A sort of hybrid standard. Includes six voice channels based on the Digital Enhanced Cordless Telecommunication (DECT) standard and the 802.11 wireless- Ethernet specification for data. SWAP devices make 50 hops per second and transmit at 1 Mbps. Uses FHSS as the method of communication.

4. **Wireless Ethernet Compatibility Alliance (WECA) or Wi-Fi for “wireless fidelity” – Seal of approval of the IEEE 802.11B. Focuses of DSSS because of the higher data rates, up to 11 Mbps. Wi-Fi offers Ethernet speeds without the wires.

Wireless Standards

Standard

GHz Spectrum

Speed Channels

802.11b 2.4 gigahertz

11 Mbps 3 Channels

802.11a 5.0 gigahertz

54 Mbps 8 Channels

802.11g 2.4 gigahertz

54 Mbps 3 Channels

Security Issues Virtual Private Network - Access

controlled by Radius MAC Authentication

Supports Wired Equivalency Privacy (WEP) Standard – an IEEE 802.11b feature designed to provide data confidentiality

Equally vulnerable as a wired network Physical Security of the Laptops

Key Components - WLAN

Wired NetworkAccess Point

Server

Fixed Node

Mobile Node Mobile Node

Wired Network

Access Point

Server

Fixed Node

Mobile Node Mobile Node

Access Point – The network device thatlinks wireless clients to the wirednetwork -- $900/unit

Wireless Adapters – Radio transceivers in the mobile nodes -- $75/ea(Cards or Integrated)

Deployment Issues Determining the Scope

Ascertain how much coverage you require based on how many users, computers and types of applications

Choosing the Computers Integrated wireless; RJ45; upgradablity

Surveying the Site Determine how many and placement of access points

Evaluating the Technology Scalability; Compatibility; Security; Roaming

Capabilities Procuring the Components

Access point; wireless adapters Installing the Systems

Configuring and installing the access points

Advantages of Wireless Laptops

Ease of movement More Time on Task Better Classroom Arrangement Strategic Deployment and Flexibility Cost Low Profile Convenience and Simple to Use

Lessons Learned Cart Selection

Locks Wheels Power

Requirements Retractable

Drawers Retractable Power

Cable Aesthetics

Lessons Learned Laptop Selection

Integrated Card Upgradeable Integrated RJ45 Dual Bay

Lessons Learned Connection

Flexibility Wired Desktops Wireless Laptops High/Low

Lessons Learned Technology As

Appropriate Music Art Special Needs Science Library

Lessons Learned Staff Readiness Is

a Prime Issue

Are your teachers and staff ready to be

unplugged?

Areas to Monitor(Challenges/Opportunities)

Battery Life Bandwidth Interference Security Migration Path – Which

standard to choose for future expandability?802.11a or 802.11g?

Give SocietyGive SocietyA FutureA Future

Give Kids a Chance

dborel@houstonisd.org gteeter@houstonisd.org