Access Control: Query the Access Control Expert

Wires and Networks Q: Do I run wires for all types of networks in the same way? A: No. Some use a bus or backbone layout, others connect to each other, and others all connect to a central point. Still others mix portions of each type to form...

Flexible, Contactless Readers
Indala Corporation offers a series of MIFARE sector readers, which includes two models (wall switch and mullion-mount), four bezel styles, and several popular colors (black, white, beige, blue, and gray). The new readers are compatible with any MIFARE application and data format, which increases their flexibility. With their clip-on bezel design, the readers are literally a snap to install. As with all Indala products, the new MIFARE series is supported by Indala's customer care, fast shipping, and a Lifetime Warranty.

One of the great things about the Indala MIFARE reader is its flexibility. You can read the card serial number or, for higher security, any sector on the card you choose, states Marc Freundlich, Indala president. You can choose what keys/password protect the data inside. And, you can select from any of the great Indala reader cover designs since they are all interchangeable.

Indala also launches its FlexPass Heavy-Duty PinProx Keypad, which combines both a proximity reader and keypad in one small package. Designed to mount on a wall box or a flat surface, the fully-potted, metal keypad is weather and vandal-resistant. Constructed of PC/ABS Copolymer material, the Heavy-Duty PinProx Keypad operates from 4-16V, and is available in beige and black. The reader can be field programmed using the FlexPass ProxSmith Programmer as well as configured to output data in either Wiegand or magnetic stripe formats.

All Identification Types
Now available from Keri Systems is the BioPointe Fingerprint Reader with Wiegand output. For use on the PXL-500W Tiger Controller or any other manufacturer's Wiegand-compatible controller, each standard unit can store 720 user templates in memory while the optional Extended Memory units can store 4400 templates.

With its integrated keypad, BioPointe combines into a single unit many of the functions that require multiple products from other manufacturers. Individual users can be assigned to require PIN + fingerprint, fingerprint-only, or keypad-only. For those customers who prefer the optional embedded proximity reader to preload the fingerprint template, the same functions apply such that selected users can be assigned card-only status. BioPointe readers with embedded proximity are compatible with both Pyramid Series and HID cards/tags.

When multiple readers are employed in a system, they can be connected via an RS-485 network so that fingerprint templates can be shared from the enrollment reader to the other readers on the system via Keri's BioPointe Central software, which also provides management and reporting capabilities. When used with the optional KES-12 Hamster Enrollment Station, enrollment parameters can be optimized and enrolled users can be uploaded directly to the network. For more information, visit

A Token Ring
Q: What about token ring, how does that compare?

A: All the devices in a ring topology network are serially connected to one another in a closed circle of twisted pair or fiber-optic cable, so that each device is connected directly to two other devices, one on either side of it. There are no terminated ends to the cable. There may or may not be a fileserver.

Under the ring concept, a message is transferred clockwise sequentially via a token from one device to the next. When a device wants to transmit, it grabs the token, attaches data and an address to it, and then sends it around the ring. The token travels along the ring until it reaches the destination address. The receiving device acknowledges receipt with a return message to the sender. The sender then releases the token for use by another device. Each device on the ring has equal access but only one device can talk at a time. Ring topology is active because each device repeats or boosts the signal before passing it on to the next device.

Because the signal is regenerated by each node, the ring topology is expandable and adding devices has minimal impact on performance. All stations have equal access to the network. In a single ring topology, if one of the devices on the ring fails, than the ring is broken and cannot work.

A dual ring or counter-rotating ring consists of two rings transmitting in opposite directions. The intent is to provide fault tolerance in the form of redundancy in the event of a cable failure. If one ring goes, the data can flow across to the other path, thereby preserving the ring.

Residential Telephone Entry System
Channel Vision introduces the TE110, a reliable and cost-effective telephone entry system. The TE100 allows for communication between the front door and any phone line in the house. When a visitor presses the doorbell at the front door, the phones in the house will ring with a distinctive tone.

The TE110 also offers the ability to control a door strike with the use of an optional relay module (TE110DS) that is sold separately. The TE110 is composed of a printed circuit board (PCB) mounted in a 12x71/2 enclosure attached by a metal mounting bracket. The PCB unit can be purchased separately. Also available is the option to create a basic door entry system using the IU-series front door intercom included in the TE110BK or TE110WT kits.

For more information, visit

Branching Out
Q: What is a tree topology and how is it used?