cel@MITRE-BEDFORD.ARPA (09/11/86)
At the Aug 28 NETBIOS meeting in Monterey, CA two proposals for
implementing NETBIOS on TCP/IP were discussed. One of the areas in which
these proposals differ pertained to the NETBIOS datagram service. The essence
of the differences relative to this area is outlined below. We would
appreciate your comments about the relative merits and implementation
feasibility/difficulty of the alternative proposals to accomplish datagram
service. Please send your comments to:
netbios@mitre-bedford.arpa
(NOTE: In both proposals IP datagrams are not broadcast out on the
internet, i.e. WAN.)
First Proposal
a) Use NETBIOS Name service to discover target UDP port and IP address
Since a name cache is assumed to be at each node, only infrequently
would name queries result in traffic on the channel.
b) Datagrams sent to a unique name are sent as directed UDP datagrams
with control info and data contained within.
c) Datagrams sent to a group name or broadcast use IP subnet broadcast
Second Proposal
a) All NETBIOS datagrams would be IP subnet broadcast UDP datagrams.
No name lookup is required.
b) UDP datagrams would contain control info and data
ISSUES
1. Is the first proposal's assumption of a name cache good? (note:
IBM's PC Network uses a cache at each node)
NOTE: If a name cache is not used then each NETBIOS datagram would
result in a broadcast name query, one or more responses and
the directed UDP containing the NETBIOS datagram. All hosts
would have to process the name query.
2. Proposal two would require all hosts on the subnet to process the
IP datagrams - even those not using NETBIOS. The assumption here
is that the NETBIOS datagram service is infrequently used and thus
hosts that are not the intended recipient would not be overly
burdened.
Is infrequent use of directed NETBIOS datagrams a good assumption?
Are slow listeners going to miss datagrams?
Thanks --- Lee LaBarre