Chapter 1 General Information
MX-2100/2104
Installation and Operation Manual
1-16 Application Considerations
1.3 Application Considerations
Basic MX-2100 System
Basic System Structure
The basic MX-2100 system consists of two MX-2100 units connected by a single
link, as shown in
MX-2100
MX-2100
Modem
Modem
KML
KML
I/O
M
od
ul
es
I/
O
M
odul
es
Figure 1-9. Basic MX-2100 System Structure
System Multiplexing Capabilities
To provide the flexibility necessary to support up to 12 I/O modules of various
types for the MX-2100 or up to 4 I/O modules of various types for the MX-2104,
with each module capable of operation in several modes, the system uses
permanent on-demand allocation of main link bandwidth. This means that
bandwidth is permanently allocated to the active channels of each module when
the module is inserted into the enclosure, and the allocation is made in
accordance with the selected data rate and the end-to-end signaling requirements
of each channel. The main link bandwidth is dynamically reallocated when a
change occurs in the number of modules or of active module channels, or when
the operating mode of the main link or of the modules are changed. For special
applications, the user can disable the automatic allocation and perform manual
allocation.
Although in general, dynamic on-demand bandwidth allocation requires that the
link is resynchronized after each change in allocation, the allocation algorithm
used by MX-2100 has been optimally designed so that it does not require
resynchronization. It only requires reallocation of time slots, thereby reducing the
disruption to other channels when the bandwidth required by a module or a
module channel changes. In many cases, the required changes are made even
without time slot reallocation: for example, disconnecting or reducing the data rate
carried by a channel never requires reallocation.
Bandwidth allocation is performed by organizing the data in frames. Frame length
varies with the main link data rate, as listed in