# # For a description of the syntax of this configuration file, # see the file kconfig-language.txt in the NuttX tools repository. # menu "TCP/IP Networking" config NET_TCP bool "TCP/IP Networking" default n ---help--- Enable or disable TCP networking support. config NET_TCP_NO_STACK bool "Disable TCP/IP Stack" default n select NET_TCP ---help--- Build without TCP/IP stack even if TCP networking support enabled. if NET_TCP && !NET_TCP_NO_STACK 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_REASSEMBLY bool "TCP reassembly" default n depends on EXPERIMENTAL ---help--- Enable support for IP packet reassembly of fragmented IP packets. This features requires an additional amount of RAM to hold the reassembly buffer and the reassembly code size is approximately 700 bytes. The reassembly buffer is of the same size as the d_buf buffer (configured by CONFIG_NET_xxx_MTU). Note: IP packet reassembly is not heavily tested (and, hence, EXPERIMENTAL). if NET_TCP_REASSEMBLY config NET_TCP_REASS_MAXAGE int "IP fragment timeout" default 200 ---help--- The maximum time an IP fragment should wait in the reassembly buffer before it is dropped. Units are deci-seconds, the range of the timer is 8-bits. Default: 20 seconds. endif # NET_TCP_REASSEMBLY 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 select MM_IOB ---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. But, if disabled, there will probably be more packet retransmissions or even packet loss. Make sure that you check the setting in the I/O Buffering menu. These settings are critical to the reasonable operation of read- ahead buffering. if NET_TCP_READAHEAD endif # NET_TCP_READAHEAD config NET_TCP_WRITE_BUFFERS bool "Enable TCP/IP write buffering" default n select MM_IOB ---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_FEATURES select 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 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 && !NET_TCP_NO_STACK config NET_TCP_RWND_CONTROL bool "Receive window control based on IOBuffer" default n depends on MM_IOB && EXPERIMENTAL ---help--- Support receive window control based on I/O buffer. This feature is still experimental. endmenu # TCP/IP Networking