Instruction manual

Designing and Planning an M2150 System
Access Control Design Guide 21
The system remembers which zone each card is in and updates this information whenever the card is used
at a zonal antipassback reader. An antipassback alarm or event is generated if the reader's from zone
does not match the card's currently-recorded zone. For example, an alarm or event is generated if the from
zone of the reader is zone 3, but the card is currently recorded as being in zone 1.
Doors should be controlled by entry and exit readers to enable the system to know which zone a card is in.
The "two readers at one door" feature can be used for this purpose (see page 23).
Commands are available in the SMS software to reset a card's zone if the currently-recorded zone gets out
of step with its actual zone (e.g. because the person has passed through a fire exit during a fire drill).
If zonal antipassback is required, specify each reader's "to" and "from" zone, in the range 1 to 63.
Zonal Antipassback Partitioning
For each zonal antipassback reader, it is essential to consider the database unit that will manage the
reader, and the chain that the database unit is in, since different database units or chains can create totally
independent zonal antipassback schemes. Partitioning may be desirable to simplify system management in
large systems, or to prevent the need to keep SMS PCs online, as described next.
The partitioning of zonal antipassback depends on the type of communications used between the SMS
software and the database units:
• LAN communications – If a LAN is used to communicate with database units, the SMS software
uses a single, system-wide, zonal antipassback scheme if the Zonal (Global System) option is
selected in the Install/Chains/LAN screen. If two or more schemes are needed, Zonal (Global
Client) should be selected. In this case, readers in LAN chains that communicate with the same
SMS client are in the same antipassback scheme. Therefore, if different zonal antipassback
schemes are required, you will need to make sure that the system design includes one SMS client
PC for each scheme, and that the readers are in the appropriate chains. Each SMS client PC can
manage up to 16 LAN chains containing zonal antipassback readers.
A factor to consider is that if readers in the same antipassback scheme are on different database
units, it is important for the SMS client that manages communication to the LAN chain to remain
switched on, as well as the server. SMS clients manage antipassback messaging within a chain, and
the SMS server manages antipassback messaging across chains. A preferable design is to ensure
that all readers in the same scheme are connected to the same database unit, if possible.
• Serial communications – If serial communications is used between SMS clients and the database
units, separate zonal antipassback schemes exist for each chain or for each database unit,
depending on whether Zonal (Chain) or Zonal (Local) is selected in the Install/Access Control/Node
screen. You cannot have system-wide zonal antipassback when using serial communications.
Preferably, Zonal (Chain) should be used only if there are more readers than can be managed by a
single database unit (16). If Zonal (Chain) is used and readers in the same antipassback scheme
connect to different database units, it is important for the SMS client that is connected to the chain to
remain switched on to handle antipassback messaging.
It is not possible to have a mix of Zonal (Chain) and Zonal (Local) settings for the same chain.
If modem communication is used to a chain on a remote site, Zonal (Local) is the only choice.
During system design, consider the database unit that each reader needs to connect to. If you do not
plan this carefully, you may not be able to achieve the desired antipassback scheme.