Internet Standards/CD1.mdf/INET/IETF/TPIX/93JUL.MIN

Text File | 1993-09-23 | 5.7 KB | 178 lines

CURRENT_MEETING_REPORT_

Reported by Vladimir Sukonnik/Process Software Corporation

Minutes of the TP/IX Working Group (TPIX)


First Session Agenda

   o AD assignment plan
   o Transit network policy


Status of the TP/IX Proposal

The session started with Vladimir Sukonnik's short presentation on the
status of TP/IX and RAP projects.  RAP version 1 has been released as a
commercial product by Process Software Corporation.  The work has begun
on implementing TP/IX in future releases of the product.  Two
Experimental RFCs have been published describing RAP and TP/IX, thus
setting the stage for vendor prototype implementation.  Vladimir has
also outlined the main features of TP/IX and how they compare to other
IPng proposals.


Transit Network Selection

Robert Ullmann described the Transit Network Selection Internet-Draft.
The document outlines an approach to allow network users to select the
carrier the same way the telephone customers in the US can select a
long-distance provider.  The idea is that the border router managed by
the customer must be able to acquire knowledge in real time of
the availability and costs of the transit networks, and be able to
select one for each datagram forwarded to the external router.


Administrative Domain Assignment Plan

Robert presented an idea on how to assign Administrative Domain
numbers for the version 7 Internet.  The objective is to use a very
small amount of space in the numbering system, while providing the
necessary distribution of authority.  AD numbers are assigned out of the
same numbering plan as version 4 network numbers.  This helps prevent
confusion when the first part of an IPv7 8-byte address is erroneously
used as an IPv4 address.  It also may be useful in routing ADs with
existing routing protocols.  The AD 192.0.0 is assigned to the present
version 4 numbering plan.  This AD has a specific plan for assignment
within it:

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   o The first 24 bits are the AD (192.0.0).
   o The next 8 to 24 bits are a network number, each assigned to a
     specific organization.
   o The remaining 16 to 40 bits are assigned to subnets and hosts by
     authority reserved to a specific organization.


Transition

Tim Dixon asked Robert and Vladimir to elaborate on the transition
plan for TP/IX. As noted in RFC 1475, it is possible to provide a
mostly-transparent bridge between IPv7 and IPv4.  Most of the
translation should consist of copying various fields, verifying fixed
values in the datagram being translated, and setting fixed values in
the datagram being produced.  The objective of the conversion is to be
able to upgrade systems, both hosts and routers, in whatever order
desired by the owners.  Organizations must be able to upgrade any
given system without reconfiguration or modification of any other
system; IPv4 hosts must also be able to interoperate essentially forever.


Future Plans

Robert was asked to elaborate on the future plans for TP/IX:


   o RAP version 1 is done and shipping.
   o Prototype TP/IX is planned to be shipped in the next release of the
     software.
   o Design is ready for vendor prototype.


Second Session Agenda

   o TCP large window/performance options
   o Record Marking option


In the second day of the working group meeting, Robert described
the TCP version 7 options Internet-Draft.  By enlarging the TCP window
and sequence number fields to 64 bits, we can avoid the problem that
TCP v4 is having now.  Mainly, the wrap-around time with the current TCP
version is relatively short for fast networks.


Selective Acknowledgement Option

There is a new option to allow the receiver to indicate that some block
of data, not ``connected'' to the left (start) edge of the TCP window,
has been received.  This option will allow unnecessary retransmissions

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to be avaided.  Only lost segments will be retransmitted, not the whole
window.  This option is useful on connections with large RTTs and large
bandwidths.


Timestamp Option

There is a new option to accurately measure the round-trip delay of the
network path being used for a TCP connection.  It contains a timestamp
value selected by the sending TCP, and a copy of the most
recently-received timestamp from the other TCP.


Record Mark Option

This option indicates the boundary of an application record.  The record
mark is constructed by the TCP service interface at the sender, and
passed to the receiver's service interface.  It is not used directly by
the TCP, except that the TCP may use record marks as hints for where
segments might be divided for maximum performance.


Large Port Number Field

Another proposal is to increase the TCP/UDP port number fields to
32 bits.  The current version is suffering from ``port burn-out.''  The
current field size of 16 bits will max out at 16K connections in four
minutes.  Port numbers are divided into several ranges:


0             Reserved
1-32767       Internet registered (well-known) protocols
32768-98303    Reserved to allow TCPv7-TCPv4 conversion
98304 up      Dynamic assignment


Attendees

Frederik Andersen        [e-mail]
Anders Baardsgaad        [e-mail]
Fred Baker               [e-mail]
Jim Bound                [e-mail]
Thomas Cordetti          [e-mail]
Al Costanzo              [e-mail]
Geert Jan de Groot       [e-mail]
Tim Dixon                [e-mail]

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Kurt Dobbins             [e-mail]
Kjeld Borch Egevang      [e-mail]
Eric Fleischman          [e-mail]
Phil Irey                [e-mail]
William Simpson          [e-mail]
Vladimir Sukonnik        [e-mail]
Robert Ullmann           [e-mail]



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