Devices llc1(7D)
NAME
llc1 - Logical Link Control Protocol Class 1 Driver
SYNOPSIS
#include
#include
#include
#include
DESCRIPTION
The llc1 driver is a multi-threaded, loadable, clonable,
STREAMS multiplexing driver supporting the connectionless
Data Link Provider Interface, dlpi(7P), implementing IE
802.2 Logical Link Control Protocol Class 1 over a STREAM to
a MAC level driver. Multiple MAC level interfaces installed
within the system can be supported by the driver. The llc1
driver provides basic support for the LC1 protocol. Func-
tions provided include frame transmit and receive, XID, and
TEST, multicast support, and error recovery and reporting.
The cloning, character-special device, /dev/llc1, is used to
access all LC1 controllers configured under llc1.
The llc1 driver is a "Style 2" Data Link Service provider.
All messages of types MPROTO and MPCPROTO are interpreted
as DLPI primitives. An explicit DLATACHREQ message by
the user is required to associate the opened stream with a
particular device (ppa). The ppa ID is interpreted as an
unsigned long and indicates the corresponding device
instance (unit) number. An error (DLERORACK) is returned
by the driver if the ppa field value does not correspond to
a valid device instance number for this system.
The values returned by the driver in the DLINFOACK primi-
tive in response to the DLINFOREQ from the user are as
follows:
o The maximum Service Data UNIT (SDU) is derived from
the MAC layer linked below the driver. In the case
of an Ethernet driver, the SDU will be 1497.
o The minimum SDU is 0.
SunOS 5.11 Last change: 13 Feb 1997 1
Devices llc1(7D)
o The MAC type is DLCSMACD or DLTPR as determined
by the driver linked under llc1. If the driver
reports that it is DLETHER, it will be changed to
DLCSMACD; otherwise the type is the same as the
MAC type.
o The sap length value is -1, meaning the physical
address component is followed immediately by a 1-
octet sap component within the DLSAP address.
o The service mode is DLCLDLS.
o The MAC type is DLCSMACD or DLTPR as determined
by the driver linked under llc1. If the driver
reports that it is DLETHER, it will be changed to
DLCSMACD; otherwise the type is the same as the
MAC type.
o The dlsap address length is 7.
o No optional quality of service (QOS) support is
included at present, so the QOS fields should be
initialized to 0.
o The DLPI version is DLVERSION2.
o The provider style is DLSTYLE2.
o The broadcast address value is the broadcast
address returned from the lower level driver.
Once in the DLATACHED state, the user must send a
DLBINDREQ to associate a particular Service Access Point
(SAP) with the stream. The llc1 driver interprets the sap
field within the DLBINDREQ as an IE 802.2 "SAP," there-
fore valid values for the sap field are in the [0-0xF]
range with only even values being legal.
The llc1 driver DLSAP address format consists of the 6-
octet physical (e.g., Ethernet) address component followed
immediately by the 1-octet sap (type) component producing a
7-octet DLSAP address. Applications should not hard-code to
this particular implementation-specific DLSAP address for-
mat, but use information returned in the DLINFOACK primi-
tive to compose and decompose DLSAP addresses. The sap
length, full DLSAP length, and sap/physical ordering are
included within the DLINFOACK. The physical address
length can be computed by subtracting the absolute value of
the sap length from the full DLSAP address length or by
issuing the DLPHYSADREQ to obtain the current physical
SunOS 5.11 Last change: 13 Feb 1997 2
Devices llc1(7D)
address associated with the stream.
Once in the DLBOUND state, the user may transmit frames on
the LAN by sending DLUNITDATAREQ messages to the llc1
driver. The llc1 driver will route received frames up all
open and bound streams having a sap which matches the IE
802.2 DSAP as DLUNITDATAIND messages. Received frames are
duplicated and routed up multiple open streams if necessary.
The DLSAP address contained within the DLUNITDATAREQ and
DLUNITDATAIND messages consists of both the sap (type) and
physical (Ethernet) components.
In addition to the mandatory, connectionless DLPI message
set, the driver additionally supports the following primi-
tives:
The DLENABMULTIREQ and DLDISABMULTIREQ primitives
enable/disable reception of specific multicast group
addresses. A set of multicast addresses may be iteratively
created and modified on a per-stream basis using these prim-
itives. These primitives are accepted by the driver in any
driver state that is valid while still being attached to the
ppa.
The DLPHYSADREQ primitive returns the 6-octet physical
address currently associated (attached) to the stream in the
DLPHYSADRACK primitive. This primitive is valid only in
states following a successful DLATACHREQ.
The DLSETPHYSADREQ primitive changes the 6-octet phy-
sical address currently associated (attached) to this
stream. Once changed, all streams subsequently opened and
attached to this device will obtain this new physical
address. Once changed, the physical address will remain set
until this primitive is used to change the physical address
again or the system is rebooted, whichever occurs first.
The DLXIDREQ/DLTESTREQ primitives provide the means for
a user to issue an LC XID or TEST request message. A
response to one of these messages will be in the form of a
DLXIDCON/DLTESTCON message.
The DLXIDRES/DLTESTRES primitives provide a way for the
user to respond to the receipt of an XID or TEST message
that was received as a DLXIDIND/DLTESTIND message.
SunOS 5.11 Last change: 13 Feb 1997 3
Devices llc1(7D)
XID and TEST will be automatically processed by llc1 if the
DLAUTOXID/DLAUTOTEST bits are set in the DLBINDREQ.
FILES
/dev/llc1 cloning, character-special device
ATRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
ATRIBUTE TYPE ATRIBUTE VALUE
Architecture x86
SEE ALSO
attributes(5), dlpi(7P)
SunOS 5.11 Last change: 13 Feb 1997 4
|
