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Chapter 2: Over view
2. Overview
2.1 Introduction
Pro Switching System 4 Network Backup Switches are 1U 19" rackmountable layer 1 switches. They are designed to switch RJ-45
copper circuits or SC fiber optic connections using high reliability telecommunications relays or micro mirror fiber optic switch
mechanisms. The various connections through the switch can be individually controlled, or all connections can be simultaneously
controlled. The Network Backup Switches (NBS) models connect the COMMON ports (C ports ) to either their associated A ports
or to their B ports.
Figure 2-1. Pro Switching System 4-gang switch.
All the RJ-45 models use high reliability telecommunications-grade latching relays to electrically connect the selected ports. The
fiber optic models use proprietary latching optical switch mechanisms to optically connec t the selected ports. Both types of
switches are transparent to data rates, protocols, formats and signal levels, and since they use latching mechanisms, they will
maintain the selected connection state and will continue to pass data between the selected ports even if power to the switch fails
or is removed.
NOTE: There are two types of RJ-45 models available. The first type includes 8- and 16-port versions that switch four leads on the
RJ-45 connector (pins 1, 2, 3 and 6). These models are suitable for use in 10/100BASE-T Ethernet environments, as T1
circuit switches, and in other similar applications where no more than four connections (t wo pairs of leads) are used. The
second type of RJ-45 models switch all eight leads. These models can be used in 10/100/1000BASE-T environments, for
switching RS-232 circuits that use both data and hardware handshake leads, and in other similar applications that require
more than four leads.
The fiber optic models are available in 4- and 6 -port versions and have SC duplex connectors.
The switch also supports connecting multiple switches together using the gang-in and gang-out connectors to allow
up to 255 NBS004A, NBS004MA, NBS006A, or NBS006MA “racks” to be daisychain-connected together so that they can be
controlled as a single system. If all of the daisychain-connected “racks” are 6 por t models, the complete system can have as many
as 1530 “ports.” You can control the complete system manually using the front panel control switches, or remotely via the serial
or Ethernet remote interfaces.
You can manually control all ports through a momentary toggle switch on the front of the unit, enabled by a removable keylock
style switch. With the keylock switch in the enabled position, all ports in that switch can be simultaneously switched by pressing
the momentary toggle switch. An entire system of daisychained racks can also be switched manually from any of the racks in the
daisychain (if the keylock switch on that rack is in the enabled position ) by holding in the system pushbutton switch while
operating the front panel momentary toggle switch.
All the switch models have a serial RS-232 interface that allows the user to control the “system,” a “rack,” or individually switch
“ports,” as well as monitor switch status. An Ethernet interface (10BASE-T) that is included on network manageable models also
allows remote control and monitoring using telnet, SNMP, a web browser, or with the provided SwitchCenter java based GUI
application program.