:orphan:

.. title:: NET_TCP_RETRY_COUNT

.. option:: CONFIG_NET_TCP_RETRY_COUNT

*Maximum number of TCP segment retransmissions*

Type: ``int``

Help
====

The following formula can be used to determine the time (in ms)
that a segment will be be buffered awaiting retransmission:
n=NET_TCP_RETRY_COUNT
Sum((1<<n) * NET_TCP_INIT_RETRANSMISSION_TIMEOUT)
n=0
With the default value of 9, the IP stack will try to
retransmit for up to 1:42 minutes.  This is as close as possible
to the minimum value recommended by RFC1122 (1:40 minutes).
Only 5 bits are dedicated for the retransmission count, so accepted
values are in the 0-31 range.  It's highly recommended to not go
below 9, though.
Should a retransmission timeout occur, the receive callback is
called with -ECONNRESET error code and the context is dereferenced.

Direct dependencies
===================

\ :option:`NET_TCP <CONFIG_NET_TCP>` && !\ :option:`NET_RAW_MODE <CONFIG_NET_RAW_MODE>` && \ :option:`NETWORKING <CONFIG_NETWORKING>`

*(Includes any dependencies from ifs and menus.)*

Default
=======

- 9

Kconfig definition
==================

.. highlight:: kconfig

At ``subsys/net/ip/Kconfig:389``

Included via ``Kconfig:8`` → ``Kconfig.zephyr:34`` → ``subsys/Kconfig:37`` → ``subsys/net/Kconfig:87``

Menu path: (Top) → Sub Systems and OS Services → Networking → Link layer and IP networking support → IP stack → Enable TCP

.. parsed-literal::

    config NET_TCP_RETRY_COUNT
    	int "Maximum number of TCP segment retransmissions"
    	default 9
    	depends on \ :option:`NET_TCP <CONFIG_NET_TCP>` && !\ :option:`NET_RAW_MODE <CONFIG_NET_RAW_MODE>` && \ :option:`NETWORKING <CONFIG_NETWORKING>`
    	help
    	  The following formula can be used to determine the time (in ms)
    	  that a segment will be be buffered awaiting retransmission:
    	  n=NET_TCP_RETRY_COUNT
    	  Sum((1<<n) * NET_TCP_INIT_RETRANSMISSION_TIMEOUT)
    	  n=0
    	  With the default value of 9, the IP stack will try to
    	  retransmit for up to 1:42 minutes.  This is as close as possible
    	  to the minimum value recommended by RFC1122 (1:40 minutes).
    	  Only 5 bits are dedicated for the retransmission count, so accepted
    	  values are in the 0-31 range.  It's highly recommended to not go
    	  below 9, though.
    	  Should a retransmission timeout occur, the receive callback is
    	  called with -ECONNRESET error code and the context is dereferenced.

*(The 'depends on' condition includes propagated dependencies from ifs and menus.)*