[comp.protocols.tcp-ip] VMTP

mason@dsg.Stanford.EDU (Tony Mason) (05/23/89)

The second release of the UNIX VMTP implementation (corresponding to RFC-1045)
is now available for the Sun-3, Sun-4, Vax, and DECstation 3100 via anonymous
FTP from gregorio.stanford.edu.

There is a vmtp.README file in the directory vmtp-ip on Gregorio which
describes the full distribution (it is distributed with individual pieces
containing the architecture specific sections.)

For those unfamiliar with VMTP here is a brief description of its salient
features:

    - VMTP is a transport level protocol.  This implementation uses the
      Berkeley socket abstraction in 4.3 and 4.3 derived systems.

    - VMTP is a reliable transport protocol providing support for
      "transactions"  rather than UDP's datagrams and TCP's connected
      streams.   It is designed to optimize performance of modern RPC style
      protocols, a service not well filled by either TCP or UDP.

    - VMTP provides real-time capabilities (elimination of checksumming on
      data or on the entire packet,) idempotent responses (e.g. responses
      from a time server,) and high-throughput rates requiring minimal 
      packet exchanges. 

Additional information about VMTP is available in RFC-1045, as well as via
the vmtp-ip mailing list (vmtp-ip@gregorio.stanford.edu.  Add/drop requests
to vmtp-ip-request@gregorio.stanford.edu.)

Tony Mason
Distributed Systems Group
Stanford University
mason@pescadero.stanford.edu

May 22, 1989

LISCHKA_J@CUBLDR.COLORADO.EDU (06/07/90)

I'm designing a network in which a host running UNIX System 5 and
using TCP-IP over Ethernet sends the same message to 16
workstations.  Rather than send the same message 16 times, would
like to broadcast the message to the workstations only once.
Can't use UDP because the workstations have to acknowledge
receipt of the update.  Do you know if there are any flavors of
VMTP that will do what I need?