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#
# For a description of the syntax of this configuration file,
# see misc/tools/kconfig-language.txt.
#
menu "TCP/IP Networking"
config NET_TCP
bool "TCP/IP Networking"
default n
---help---
TCP support on or off
if NET_TCP
config NET_TCPURGDATA
bool "Urgent data"
default n
---help---
Determines if support for TCP urgent data notification should be
compiled in. Urgent data (out-of-band data) is a rarely used TCP feature
that is very seldom would be required.
config NET_TCP_CONNS
int "Number of TCP/IP connections"
default 8
---help---
Maximum number of TCP/IP connections (all tasks)
config NET_MAX_LISTENPORTS
int "Number of listening ports"
default 20
---help---
Maximum number of listening TCP/IP ports (all tasks). Default: 20
config NET_TCP_READAHEAD
bool "Enable TCP/IP read-ahead buffering"
default y
---help---
Read-ahead buffers allows buffering of TCP/IP packets when there is no
receive in place to catch the TCP packet. In that case, the packet
will be retained in the NuttX read-ahead buffers.
You might want to disable TCP/IP read-ahead buffering on a highly
memory constrained system that does not have any TCP/IP packet rate
issues.
if NET_TCP_READAHEAD
config NET_TCP_READAHEAD_BUFSIZE
int "TCP/IP read-ahead buffer size"
default 1220 if !NET_SLIP && NET_IPv6
default 536 if !NET_SLIP && !NET_IPv6
default 256 if NET_SLIP && !NET_IPv6
---help---
Read-ahead buffers allows buffering of TCP/IP packets when there is no
receive in place to catch the TCP packet. In that case, the packet
will be retained in the NuttX read-ahead buffers.
This setting specifies the size of one TCP/IP read-ahead buffer.
This should best be a equal to the maximum packet payload size (MSS).
Optimally, the size of the read-ahead buffer will should the maximum
size of an incoming TCP packet payload (MSS). This MSS value is
determined by NET_BUFSIZE minus the size of TCP, IP, and Ethernet
headers (assuming you are using the Ethernet transport). IPv4 hosts
are required to be able to handle an MSS of 536 octets and IPv6 hosts
are required to be able to handle an MSS of 1220 octets.
config NET_NTCP_READAHEAD_BUFFERS
int "Number of TCP/IP read-ahead buffers"
default 8
---help---
Read-ahead buffers allows buffering of TCP/IP packets when there is no
receive in place to catch the TCP packet. In that case, the packet
will be retained in the NuttX read-ahead buffers.
This setting specifies the number of TCP/IP read-ahead buffers.
endif # NET_TCP_READAHEAD
config NET_TCP_WRITE_BUFFERS
bool "Enable TCP/IP write buffering"
default n
select NET_IOB
depends on !NET_PKT
---help---
Write buffers allows buffering of ongoing TCP/IP packets, providing
for higher performance, streamed output.
You might want to disable TCP/IP write buffering on a highly memory
memory constrained system where there are no performance issues.
if NET_TCP_WRITE_BUFFERS
config NET_TCP_NWRBCHAINS
int "Number of pre-allocated I/O buffer chain heads"
default 8
---help---
These tiny nodes are used as "containers" to support queueing of
TCP write buffers. This setting will limit the number of TCP write
operations that can be "in-flight" at any give time. So a good
choice for this value would be the same as the maximum number of
TCP connections.
config NET_TCP_WRBUFFER_DEBUG
bool "Force write buffer debug"
default n
depends on DEBUG
select NET_IOB_DEBUG
---help---
This option will force debug output from TCP write buffer logic,
even without network debug output. This is not normally something
that would want to do but is convenient if you are debugging the
write buffer logic and do not want to get overloaded with other
network-related debug output.
config NET_TCP_WRBUFFER_DUMP
bool "Force write buffer dump"
default n
depends on DEBUG_NET || NET_TCP_WRBUFFER_DEBUG
select NET_IOB_DEBUG
---help---
Dump the contents of the write buffers. You do not want to do this
unless you really want to analyze the write buffer transfers in
detail.
endif # NET_TCP_WRITE_BUFFERS
config NET_TCP_RECVDELAY
int "TCP Rx delay"
default 0
---help---
If NET_TCP_READAHEAD_BUFFERS is undefined, then there will be no buffering
of TCP/IP packets: Any TCP/IP packet received will be ACKed, but its contents
will be dropped in the bit-bucket.
One low-performance option is delay for a short period of time after a
TCP/IP packet is received to see if another comes right behind it. Then
the packet data from both can be combined. This option only makes since
if performance is not an issue and you need to handle short bursts of
small, back-to-back packets. The delay is in units of deciseconds.
config NET_TCPBACKLOG
bool "TCP/IP backlog support"
default n
---help---
Incoming connections pend in a backlog until accept() is called.
The size of the backlog is selected when listen() is called.
config NET_TCP_SPLIT
bool "Enable packet splitting"
default n
depends on !NET_TCP_WRITE_BUFFERS
---help---
send() will not return until the transfer has been ACKed by the
recipient. But under RFC 1122, the host need not ACK each packet
immediately; the host may wait for 500 MS before ACKing. This
combination can cause very slow performance with small transfers are
made to an RFC 1122 client. However, the RFC 1122 must ACK at least
every second (odd) packet.
This option enables logic to trick the RFC 1122 host be exploiting
this last RFC 1122 requirement: If an odd number of packets were to
be sent, then send() will split the last even packet to guarantee
that an even number of packets will be sent and the RFC 1122 host
will ACK the final packet immediately.
if NET_TCP_SPLIT
config NET_TCP_SPLIT_SIZE
int "Split size threshold"
default 40
---help---
Packets of this size or smaller than this will not be split.
endif # NET_TCP_SPLIT
config NET_SENDFILE
bool "Optimized network sendfile()"
default n
---help---
Support larger, higher performance sendfile() for transferring
files out a TCP connection.
endif # NET_TCP
endmenu # TCP/IP Networking
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