ID Number: Q60845
2.00 2.10
OS/2
Summary:
The following are questions and answers about LAN Manager source level
routing and OpenAdapter issues:
1. Q. What does it mean when an NDIS driver says it supports source
routing? Does this mean the NDIS driver keeps a table of routing
information for subsequent use, or does it mean that the
token-ring chipset the NDIS driver talks to keeps the routing
information? Or, does this signal JETBEUI that the data it is
receiving from the NDIS driver may have source routing
information? This would mean that when JETBEUI receives the
data, it has to know how to determine whether the source routing
field exists, and determine the length of the source routing
field in order to determine where the real data in the frame
begins.
A. If IBM source routing is used (bit 9 in MACservice specific
characteristics), it is the protocol module's responsibility to
encode and interpret appropriate source routing information.
This bit merely implies that the device is capable of sending
packets with the source routing bit set in the source address so
that a protocol may recognize such a packet.
2. Q. If a Token-ring NDIS driver says it supports the open adapter,
is it JETBEUI's responsibility to call OpenAdapter to get onto
the ring? Or should the NDIS driver open the adapter itself once
the NDIS driver has initialized the adapter?
A. If OpenAdapter (bit 11) is set, the protocol driver must ensure
that the adapter is open. The open status of an adapter can be
determined by examining bit 4 of the MAC status in the
MAC-specific status table. If the adapter is not open, the
protocol must issue an OpenAdapterRequest (normally during
bind-time processing).