Research

Barcode

Barcode systems, due to the low cost of badges and ease of setup, often seem like the best solution. However, barcode systems have a couple of problems. First, they are not always reliable when reading worn, dirty or obscured barcodes. Second, to be scanned the barcodes must be placed in the correct position and held steady. This could be difficult for someone that lacks fine motor control.

Magnetic Stripe

Magnetic stripe technology is a mature technology with a proven track record. There are many implementations of this in use today, including here at UB. The readers and writers for this type of system are common and the standards are fully established. The primary shortcomings of this technology, for our purposes, would be the difficulty involved in integrating it with an active RFID system. The system would either need to have two parts, a swipe card and a tracker, or the magnetic stripe card would need to be mounted onto the tracker. However, mounting the card on the tracker is not a workable solution, and people will likely have trouble keeping track of and using two separate means of ID.

Passive IR

Passive Infrared Detectors are sensors that detect temperature changes. Many stores use the PID to provide indication of a customer walking in/out.  This would come in handy to detect if someone is at the door or not. It can detect up to a range of 100ft. The cons of this system are that it is hackable and the sensor's performance decreases if there are sudden temperature changes in the room. Also, it would not be possible to place sensors near air vents. The pros are that users do not need to carry extra devices, such as cards or ID tags, and it's a wireless system. Another advantage is that it only communicates to one device at a time. Therefore, if you have a room full of infrared detectors, it will only communicate with one. This system could be coupled with an active RFID tracking system to unlock a door for a person in its field.

Bluetooth

Bluetooth is a wireless short range communication protocol that uses radio waves. The range of communication can be anywhere between 1 and 100 meters. In the case of transfering data from one source to another, it provides some security by prompting for connection credentials before file transfer occures. The pros involved with bluetooth include that it does not require much power to operate, it's wireless, it's inexpensive, and it is able to communicate to eight separate devices at once. Cons include that bluetooth is not secure; hacking into radio waves sent out by bluetooth is possible. If bluetooth is always left on, it can be be vulnerable to security attacks. In the past years with cell phones, there have been viruses and worms (e.g. Lasco.A, bluejacking, and bluebugging) that have spread through bluetooth.

RFID

The term 'RFID' stands for Radio-Frequency IDentification. It refers to small electronic devices that consist of a small chip and an antenna. An RFID device provides a unique identifier for an object, readable through multiple layers of material, depending on the strength of the reader's signal. The RFID device must be scanned by a reader unit to retrieve the identifying information. There are two types of RFID systems: active and passive. Passive is powered by the reader, while active requires that the chip has its own power source.

Passive

The scan time for a passive RFID tag is usually under 100 milliseconds. This can cause problems when designing software as it never stops reading until it is moved out of the field. Also, multiple tags can be read at one time. This allows for capturing data on multiple students moving through a doorway without the need for each individual to scan his or her ID card at a reader.

Smart chips or smart cards are a type of RFID technology. They can be either contact or contactless, with contactless cards having ranges varying from a few inches to a few feet.

Active

Active RFID uses powered asset tags to increase their range and capabilities. With an active RFID system you can get real-time location information in three dimensions. This allows for precise tracking and logging of a tag's location in real time. Also, many active systems now implement the Zigbee protocol, which allows for low power consumption, encryption of all data, and the ability to integrate systems from multiple vendors. Some of the tags can also be fitted with a variety of sensors, allowing for additional capabilities to be added later. The only prominent down side to active RFID is the need for a battery, which will eventually, within anywhere between three months and a year, need to be recharged or replaced.