Wireless Policies and Standards

Deployment of any wireless infrastructure needs to be carefully planned and engineered. The design and deployment of a wireless network for a particular location is influenced primarily by interference and capacity planning factors. Each design must include careful and exhaustive signal strength measurements, which take into account the three-dimensional nature of wireless network devices, interference caused by other devices utilizing the same unlicensed spectrum and obstacles such as concrete walls and metal supports.

For example, a wireless access point located on one floor of the building provides signal coverage to adjacent floors of the same building. Thus, a mobile computing lab wheeled into a classroom on the second floor and connected to the network will interfere with an access point operating on the third floor above it if configured for the same channel. In addition, microwave ovens and certain brands of cordless telephones are known to interfere with 802.11b wireless networks.

The design must also take into account the potential load on the wireless network. A large number of wireless users in one area such as a large classroom or lecture hall, for example, may require the use of two or more wireless access points configured to balance load. A less dense but more spread out coverage area, such as a lawn between two buildings may require a "coverage-oriented" as opposed to a "capacity-oriented" design with a different set of configuration options. In addition, it is important to note that the bandwidth provided by the wired network far exceeds that provided by wireless LANs. Users attempting to substitute wireless LANs for wired LANs can expect degradation of performance and speed as well as potential loss of signal from time to time.

ITS has responsibility for the design, deployment, and management of the wireless network infrastructure on the UM-Dearborn campus. This is essential to ensure a consistent and secure environment for wireless computing at the University.

Wireless networks operate in both FCC licensed and FCC unlicensed bands. Many communication products operate in these bands, and it is not unusual for one piece of equipment to interfere with another. Such interference causes degraded service quality. UM-Dearborn's wireless LAN network is based on 802.11a/b/g standard specifications, and utilizes the FCC unlicensed 2.4 & 5 GHz Industrial/Scientific/Medical (ISM) band. Various other wireless devices also utilize this band and can potentially cause interference. Independent deployment of wireless networks and products by departments or individuals can limit the accessibility and quality of service from issues relating to interference and capacity.

In order to assure the highest level of service for all members of the campus community, potential interference with the wireless network must be minimized. ITS has developed guidelines and recommendations for the use of wireless products on campus, similar to other leading Universities in the wireless networking field.

ITS will monitor use of the airspace for potential interfering devices, and will notify a user if a device is causing interference and potentially disrupting the campus network. In these cases, ITS reserves the right to restrict the use of all 2.4/5 GHz radio devices in university-owned buildings and outdoor spaces on the campus.

ITS will work with the campus community to assist in phasing out other 2.4/5 GHz devices that are specifically used for digital communications in university-owned buildings. This does not prohibit the use of microwave ovens, security alarms, telephones or other devices such as pacemakers, which make use of the 2.4/5 GHz radio frequencies. In cases where the device is being used for a specific teaching or research application, ITS will work with the individual or department to develop a solution that mitigates any potential interference. If you think you have an existing system that may use 2.4 GHz radios for transmission, or you are planning to purchase a wireless system and you are uncertain if it employs 2.4 GHz radios, please contact ITS.

The potential for unauthorized access to the University network will increase as wireless networks expand beyond buildings and potentially beyond the campus. Security features defined by the 802.11b standard are vulnerable and are unable to prevent unauthorized access or to protect data traversing the wireless medium from determined attackers.

The inherent insecure nature of the wireless network medium makes it essential that users adhere to effective security practices. These may include, but are not limited to, the use of application level authentication and encryption technologies such as Secure Socket Layer (SSL) and Secure Shell (SSH).

Wireless networks continue to be insecure with currently available technologies. Departments that require enhanced security can utilize Virtual Private Network (VPN). This will require additional end user configuration and/or the use of VPN client software. ITS provides assistance and instructions for people utilizing VPN.

Anyone accessing the UM-Dearborn wireless network is expected to comply with all applicable University policies governing the proper use of shared computer resources.