<
networking>
IBM PC local area network software that
divides data into
packets which it routes to the network.
It also handles incoming data, reassembling the packets so
that
application programs can read the data as a continuous
stream.
FTP Software created the specification for
IBM PC packet
drivers but
Crynwr Software dominate the market and have
done the vast majority of the implementations.
Packet drivers provide a simple, common programming interface
that allows multiple
applications to share a {network
interface} at the
data link layer.
Packet drivers
demultiplex incoming packets among the applications by using
the network media's
standard packet type or {service access
point} field(s).
The
packet driver provides calls to initiate access to a
specific
packet type, to end access to it, to send a
packet,
to get statistics on the network interface and to get
information about the interface.
Protocol implementations that use the
packet driver can
coexist and can make use of one another's services, whereas
multiple applications which do not use the
driver do not
coexist on one machine properly. Through use of the
packet
driver, a user could run
TCP/IP,
XNS and a proprietary
protocol implementation such as
DECnet,
Banyan's,
LifeNet's,
Novell's or
3Com's without the difficulties
associated with pre-empting the network interface.
Applications which use the
packet driver can also run on new
network hardware of the same class without being modified;
only a new
packet driver need be supplied.
There are several levels of
packet driver. The first is the
basic
packet driver, which provides minimal functionality but
should be simple to implement and which uses very few host
resources. The basic
driver provides operations to broadcast
and receive packets. The second
driver is the extended
packet
driver, which is a superset of the basic
driver. The extended
driver supports less commonly used functions of the network
interface such as
multicast, and also gathers statistics on
use of the interface and makes these available to the
application. The third level, the high-performance functions,
support performance improvements and tuning.
http://crynwr.com/crynwr/home.html.
(1994-12-05)