The Inverse Multiplexing over ATM (IMA) Emulator application can simulate the inverse multiplexing of an ATM cell stream over multiple physical links and retrieve the original stream at the far-end from these physical links. The multiplexing of the ATM cell stream is performed on a cell by cell basis across the multiple physical links. Traffic source can be sequence number, HDL files (containing packets/frames), flat binary file, user-defined frames (ASCII HEX file), and Ethernet data.

The ATM Inverse Multiplexing technique involves inverse multiplexing and de-multiplexing of ATM cells in a cyclical fashion among links grouped to form a higher bandwidth logical link whose rate is approximately the sum of the link rates. This technique provides an effective method of combining the transport bandwidths of multiple links (e.g., DS1/E1 links) grouped to collectively provide higher intermediate rates. This is referred to as an IMA grouping.

Along with AAL0 and AAL5 IMA supports AAL2 which provides bandwidth-efficient transmission of low-rate, short and variable length packets in delay sensitive applications. AAL2 also provides for variable payload within cells and across cells by using segmentation and reassembly technique. AAL type 2 is subdivided into the Common Part Sublayer (CPS) and the Service Specific Convergence Sublayer (SSCS).

GL’s IMA Emulator is available as optional client-server based application with GL’s T1/E1 Analysis hardware. GL also offers ATM analysis application for real-time capture and analysis of ATM IMA cells over T1 E1 lines. Please visit ATM Protocol Analyzer page for more details.

• Performs IMA simulation on up to 16 T1/E1 ports
• ATM links can be created on full or fractional timeslots
• Supports hyper channels with discontinuous (sparse) timeslots
• IMA Frame Length can be set equal to 32, 64, 128, or 256
• Dynamically add/remove (Open/Close) of ATM links without loss in data
• Multiple IMA groups can be created with each group configured with multiple virtual channels for traffic tx/rx.
• Generate and verify end to end traffic on each Virtual Channel
• User configurable ATM (AAL 5, AAL 2) Packet size.
• Payload traffic generation and verification using Sequence number, HDL file (containing packets/frames), Flat Binary file, and User defined frame (ASCII HEX file) for each Virtual Channel independently
• Transmit and receive Ethernet traffic over T1E1 links by operating in bridge mode
• Provides detailed statistics for all IMA groups and each Virtual Channel associated with a group
• Provides end to end traffic verification statistics
• Ideal solution for automated testing using command line scripts