Parsec — reliable and functional!

Parsec is reliable and functional!

Sergey Stasenko,
Relvest Group of Companies
sserg@relvest.ru

ParsecNET 2.5: a new level of reliability
A new version of software for the ParsecNET integrated security system has been released. The user will find very few external differences, but «inside» — this is completely different software. Maintaining a user-friendly external interface was the initial condition, as they say, don't look for good from good.
Firstly, the core of the system has undergone almost complete redesign. The ever-increasing scale of systems and their distribution require higher speeds and reliability in the transmission and processing of information. The changes affected both the data transmission mechanisms over the local network and the internal algorithms for processing and responding to system events.
The system now uses MS SQL as a DBMS. The transition from the good and familiar Paradox is due to the same reasons that are indicated just above. The volumes of information stored in large systems do not allow for the necessary speed of processing and providing this information (primarily this concerns reports and remote access to the system database). The transition to a client — server DBMS allowed us to avoid these inconveniences.
The ParsecNET system has a powerful system for recording working hours with a large number of calculation rules. However, as for the output forms of reports, no matter how general and standard they are, everyone wants to receive data in their own format and with their own set of data. Therefore, in order to avoid an avalanche of orders for adapting report forms, the new version of the system provides the user with a toolkit that allows you to quickly and easily create any custom forms for the resulting reports. Several standard forms are supplied with the system, but if the customer is not satisfied with them, he can create any number of his own forms.

Remote identification system — more versatility
During this year, the PR-G07 reader software was modified, due to which two fundamentally new built-in algorithms for recording the passage of vehicles through access points appeared. Let us recall what algorithms existed in the previous version of the reader. The main algorithm, designed to service a one-way or two-way access point, is explained in Figure 1. Figure 1. Standard access algorithm.

After reading the tag of the approaching vehicle, the reader switches to the waiting mode for the vehicle presence sensor to be triggered in the gate alignment – ​​this is the position in which the lower vehicle is fixed in the figure. After the sensor is triggered, the reader transmits the tag code to the access controller, blocks further tag reading for the duration of the algorithm processing, and waits for the gate opening sensor to be triggered. After driving through the gate, the entry reading channel is unlocked, and the reader is ready for the next operation cycle. Note that when the channels are linked, the code of the processed tag is ignored for some time by the second channel to eliminate false alarms when, after driving through the gate, the vehicle enters the reading zone of the exit channel (the vehicle in the upper position in the figure).
There was also an algorithm in which the tag was read only after the external sensor was triggered, which could be an infrared vehicle presence sensor, the output of a television number recognition system, or any other sensor.
Two newly introduced algorithms allow implementing other schemes for recording vehicles, which we will consider below.

Continuous registration mode

This mode allows recording the flow of vehicles in one or two directions without using gates or barriers. The principle of its operation is explained in Figure 2. Figure 2. Continuous registration mode.

Each channel records cars on its own channel at the speed of their movement. During oncoming traffic, due to non-overlapping reading zones, already passed tags in the oncoming channel are blocked due to the connected operation of channels, as in other algorithms.
Taking into account fluctuations when reading tags, they can arrive at the reader quite quickly — so that the access controller will not have time to process them (this situation has been observed in practice). To prevent such conflicts, the read tags are not sent to the controller immediately, but through an intermediate buffer, from which they arrive at the controller at a rate no higher than that pre-set when configuring the reader (for example, no more than two per second).
In the dual-channel mode, not only is the minimum interval between code outputs to the Wiegand output standardized, but they are also alternated by the outputs of the first and second channels. This is done again due to the fact that in real life there are ACS controllers that do not perceive two Wiegand packets simultaneously at two inputs.

Registration mode «for travel»

This is another new operating mode for the reader, which is based on the analysis of the sequence of intersection of the tag reading zones of the first and second channels. This mode is explained in Figure 3 and consists of the following. Figure 3. Registration «for travel».

When a tag first appears in one of the channels, the reader remembers it for a specified time, and when the same tag appears in the second channel, it checks for recent recording in the opposite channel. If the tag has recently been recorded in the opposite channel, a conclusion is made about the direction of movement, and the tag code is sent to the Wiegand output corresponding to the direction for transmission to the access system controller.
The tag memory time interval for ensuring the above comparison is programmed during system setup.
To configure all parameters and operating modes of the reader, an updated configuration utility is supplied with it.

Active tags

In addition to the functional changes in the reader, a new version of industrial-grade tags has appeared within the system. Unlike standard ActiveTag tags, these tags are made in a sealed dust- and moisture-proof case and are designed for mounting on a surface using 2 self-tapping screws. The use of special power supplies has made it possible to expand the operating temperature range from –40 to +50 degrees Celsius. Also, depending on the customer’s wishes, these tags can be produced with a vibration sensor and a tamper switch for breaking away from the base.

P.S. All Parsec products are Gosstandart certified. You can find more detailed information about Parsec products on the website parsec.ru, and purchase them from the following companies or their regional dealers: