NetWare 4.1/9000 Concepts

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NetWare Glossary
O
In DOS client environments, the MSM and TSMs are linked in with the
HSM so that only one module is loaded.
Link Support Layer (LSL)
The LSL is a software module that implements the interface between drivers
and protocol stacks. It essentially acts like a switchboard, directing packets
between the drivers and protocol stacks.
Any ODI LAN driver can communicate with any ODI protocol stack
through the LSL. The LSL handles the communication between protocol
stacks and MLIDs.
Because the ODI allows the physical LAN medium to support many
different types of protocols (for example, IPX, TCP/IP, AppleTalk and LAT
might all be supported on one Ethernet network adapter), the MLID receives
packets destined for different protocol stacks that might be present in the
system.
The LSL then determines which protocol stack the packet is to be delivered
to. Next, the protocol stack determines what should be done with the packet.
When the protocol stack must transmit a packet, the protocol stack hands the
packet to the LSL, which then routes the packet to the appropriate MLID.
The LSL enables the protocol stacks to handle sending and receiving.
The LSL also tracks the various protocols and MLIDs that are loaded in the
system and provides a consistent method of finding and using each of the
loaded modules.
Media Support Module (MSM)
The MSM standardizes and manages primary details of interfacing ODI
MLIDs to the LSL and operating system.
The MSM handles generic initialization and run-time issues common to all
drivers.
Topology Specific Module (TSM)
The TSM manages operations unique to a specific media type, such as
Ethernet, or Token-Ring. Multiple frame support is implemented in the TSM
so that all frame types for a given media are supported.