Introduction to MDI
The MAC (Media Access Control)
Driver Interface (MDI) is
a STREAMS-based Media Access Control (MAC)
provider interface for network device drivers.
MDI is designed
to minimize the effort involved in
developing and maintaining drivers
that support new network devices.
MDI is not exposed directly
to network protocol stacks;
developers implementing protocol stacks and complex
data-link providers should use the
Data Link Provider Interface.
NOTE:
The DLPI module for UnixWare 7
is not the same thing as the DLPI driver interface
that was used for implementing network drivers
on SCO UnixWare 1 and 2 systems.
Rather, it sits between the protocol stacks
and the MDI drivers
to provide media-specific information
and support routines for MDI drivers.
The DLPI module also performs common functions,
such as Service Access Point (SAP) demultiplexing,
source routing, and transmit monitoring.
See the
dlpid(1M)
manual page for more information.
MDI is currently defined for the following media types:
-
CSMA/CD (Ethernet-II or IEEE 802.3)
-
IEEE 802.5 Token Passing Ring
-
FDDI
-
ISDN
-
100BaseTX
-
10/100 VGAnyLAN
The MDI specification may be extended in the future
to support other media.
© 2004 The SCO Group, Inc. All rights reserved.
HDK 7.1.4 - September 2004