DOCUMENT ID:  1202-02

SYNOPSIS:     TCP/IP apps have slow response slip, ppp using pcnfs 

OS RELEASE:   2.1, 2.4

PRODUCT:      Solaris

KEYWORDS:     slow response slip ppp tcp/ip response pcnfs ndd


SYMPTOMS:

TCP/IP applications running under asynchronous communications like
"SLIP" give slow response, changing retransmit time of packets gives
improvement. 


DESCRIPTION:

Asynchronous communication using slip is very slow in respect to
classical Ethernet media.  Telnet applications with low volume input
generally from keyboards and low volumes of output like file editing
perform fairly well.  Screen based applications which take a small
amount of input and a screen of output - stock check of inventory
requiring a part number as input and a full screen of related data as
output is a good example.  Personnel records in Human Resources is
another example.  These applications fill several outbound tcp/ip
"packets".  Output bursting occurs.  Transmission of just on packet over
the asynchronous line will cause retransmission of packets.  Tcp/ip
dynamic adjustment of the retransmission time is an integral part of the
protocol.  A valid receipt of a packet is required to acquire a
"round-trip time" for use in calculations.  The performance of other
parts of a "conventional" network is not affected.  The packet
acknowledgments occur very quickly and very few retransmissions are
necessary. 


SOLUTION:

The "ndd" function allows the tcp_rexmit_interval_min to be set.  The
/etc/rc2.d/S69inet script file is a good place to set a value.  The
default value is 200 and may be increased to 1000. 


DATE APPROVED: 09/18/95