TCP Read-Ahead: Convert to use I/O buffer chains

69 files changed, 345 insertions, 138 deletions

diff --git a/nuttx/configs/c5471evm/httpd/defconfig b/nuttx/configs/c5471evm/httpd/defconfig
index 375b3e64b..ef3294ba0 100644
--- a/nuttx/configs/c5471evm/httpd/defconfig
+++ b/nuttx/configs/c5471evm/httpd/defconfig
@@ -347,8 +347,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -367,6 +365,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/c5471evm/nettest/defconfig b/nuttx/configs/c5471evm/nettest/defconfig
index 45c302cdc..0c05b25e4 100644
--- a/nuttx/configs/c5471evm/nettest/defconfig
+++ b/nuttx/configs/c5471evm/nettest/defconfig
@@ -345,8 +345,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=562
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=32
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -365,6 +363,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/c5471evm/nsh/defconfig b/nuttx/configs/c5471evm/nsh/defconfig
index b943e5d62..803f97144 100644
--- a/nuttx/configs/c5471evm/nsh/defconfig
+++ b/nuttx/configs/c5471evm/nsh/defconfig
@@ -348,8 +348,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=32
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -372,6 +370,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/cloudctrl/nsh/defconfig b/nuttx/configs/cloudctrl/nsh/defconfig
index 6aa1fb495..63ef8d27c 100644
--- a/nuttx/configs/cloudctrl/nsh/defconfig
+++ b/nuttx/configs/cloudctrl/nsh/defconfig
@@ -404,8 +404,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
 CONFIG_NET_UDP=y
@@ -420,6 +418,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 
 #
 # File Systems
diff --git a/nuttx/configs/eagle100/httpd/defconfig b/nuttx/configs/eagle100/httpd/defconfig
index 00c8f4b8b..c3a8c3b7d 100644
--- a/nuttx/configs/eagle100/httpd/defconfig
+++ b/nuttx/configs/eagle100/httpd/defconfig
@@ -414,8 +414,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -434,6 +432,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/eagle100/nettest/defconfig b/nuttx/configs/eagle100/nettest/defconfig
index 4f1b4eab0..c2ccee25d 100644
--- a/nuttx/configs/eagle100/nettest/defconfig
+++ b/nuttx/configs/eagle100/nettest/defconfig
@@ -461,8 +461,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=532
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -481,6 +479,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/eagle100/nsh/defconfig b/nuttx/configs/eagle100/nsh/defconfig
index 9410f472f..577b2c7fc 100644
--- a/nuttx/configs/eagle100/nsh/defconfig
+++ b/nuttx/configs/eagle100/nsh/defconfig
@@ -454,8 +454,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -478,6 +476,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/eagle100/thttpd/defconfig b/nuttx/configs/eagle100/thttpd/defconfig
index 77440cf34..503fa93c6 100644
--- a/nuttx/configs/eagle100/thttpd/defconfig
+++ b/nuttx/configs/eagle100/thttpd/defconfig
@@ -406,8 +406,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -426,6 +424,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ekk-lm3s9b96/nsh/defconfig b/nuttx/configs/ekk-lm3s9b96/nsh/defconfig
index 6ef2f467a..fb725cddb 100644
--- a/nuttx/configs/ekk-lm3s9b96/nsh/defconfig
+++ b/nuttx/configs/ekk-lm3s9b96/nsh/defconfig
@@ -440,8 +440,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -464,6 +462,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ez80f910200zco/httpd/defconfig b/nuttx/configs/ez80f910200zco/httpd/defconfig
index fd1a186fd..f3ed9b29e 100644
--- a/nuttx/configs/ez80f910200zco/httpd/defconfig
+++ b/nuttx/configs/ez80f910200zco/httpd/defconfig
@@ -416,8 +416,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=562
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -436,6 +434,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ez80f910200zco/nettest/defconfig b/nuttx/configs/ez80f910200zco/nettest/defconfig
index 48f5b19d6..d91299244 100644
--- a/nuttx/configs/ez80f910200zco/nettest/defconfig
+++ b/nuttx/configs/ez80f910200zco/nettest/defconfig
@@ -414,8 +414,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -434,6 +432,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ez80f910200zco/nsh/defconfig b/nuttx/configs/ez80f910200zco/nsh/defconfig
index 3d4c25bfe..ec905a780 100644
--- a/nuttx/configs/ez80f910200zco/nsh/defconfig
+++ b/nuttx/configs/ez80f910200zco/nsh/defconfig
@@ -418,8 +418,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -442,6 +440,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ez80f910200zco/poll/defconfig b/nuttx/configs/ez80f910200zco/poll/defconfig
index 78ebd9d03..39da34730 100644
--- a/nuttx/configs/ez80f910200zco/poll/defconfig
+++ b/nuttx/configs/ez80f910200zco/poll/defconfig
@@ -416,8 +416,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -436,6 +434,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/fire-stm32v2/nsh/defconfig b/nuttx/configs/fire-stm32v2/nsh/defconfig
index 302c8f65b..c2cb656b9 100644
--- a/nuttx/configs/fire-stm32v2/nsh/defconfig
+++ b/nuttx/configs/fire-stm32v2/nsh/defconfig
@@ -449,8 +449,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=16
 CONFIG_NET_TCP_READAHEAD=y
-# CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
 CONFIG_NET_UDP=y
@@ -465,6 +463,11 @@ CONFIG_NET_STATISTICS=y
 # CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 
 #
 # File Systems
diff --git a/nuttx/configs/lm3s6432-s2e/nsh/defconfig b/nuttx/configs/lm3s6432-s2e/nsh/defconfig
index ec2d618ce..995daae3f 100644
--- a/nuttx/configs/lm3s6432-s2e/nsh/defconfig
+++ b/nuttx/configs/lm3s6432-s2e/nsh/defconfig
@@ -437,8 +437,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -461,6 +459,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/lm3s6965-ek/discover/defconfig b/nuttx/configs/lm3s6965-ek/discover/defconfig
index addaa0142..47a81688c 100644
--- a/nuttx/configs/lm3s6965-ek/discover/defconfig
+++ b/nuttx/configs/lm3s6965-ek/discover/defconfig
@@ -446,8 +446,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -470,6 +468,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/lm3s6965-ek/nsh/defconfig b/nuttx/configs/lm3s6965-ek/nsh/defconfig
index addaa0142..47a81688c 100644
--- a/nuttx/configs/lm3s6965-ek/nsh/defconfig
+++ b/nuttx/configs/lm3s6965-ek/nsh/defconfig
@@ -446,8 +446,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -470,6 +468,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/lm3s6965-ek/tcpecho/defconfig b/nuttx/configs/lm3s6965-ek/tcpecho/defconfig
index fc4358e7d..c536c9bb0 100644
--- a/nuttx/configs/lm3s6965-ek/tcpecho/defconfig
+++ b/nuttx/configs/lm3s6965-ek/tcpecho/defconfig
@@ -449,8 +449,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=624
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -473,6 +471,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=624
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/lm3s8962-ek/nsh/defconfig b/nuttx/configs/lm3s8962-ek/nsh/defconfig
index f57038fa7..e12d3fb44 100644
--- a/nuttx/configs/lm3s8962-ek/nsh/defconfig
+++ b/nuttx/configs/lm3s8962-ek/nsh/defconfig
@@ -454,8 +454,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -478,6 +476,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/lpcxpresso-lpc1768/nsh/defconfig b/nuttx/configs/lpcxpresso-lpc1768/nsh/defconfig
index d3faa6919..0bd0d25a7 100644
--- a/nuttx/configs/lpcxpresso-lpc1768/nsh/defconfig
+++ b/nuttx/configs/lpcxpresso-lpc1768/nsh/defconfig
@@ -531,8 +531,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -555,6 +553,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/lpcxpresso-lpc1768/thttpd/defconfig b/nuttx/configs/lpcxpresso-lpc1768/thttpd/defconfig
index 2ffaca630..1587c899c 100644
--- a/nuttx/configs/lpcxpresso-lpc1768/thttpd/defconfig
+++ b/nuttx/configs/lpcxpresso-lpc1768/thttpd/defconfig
@@ -484,8 +484,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -504,6 +502,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ntosd-dm320/nettest/defconfig b/nuttx/configs/ntosd-dm320/nettest/defconfig
index bad3d07ad..e66240584 100644
--- a/nuttx/configs/ntosd-dm320/nettest/defconfig
+++ b/nuttx/configs/ntosd-dm320/nettest/defconfig
@@ -388,8 +388,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -408,6 +406,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ntosd-dm320/nsh/defconfig b/nuttx/configs/ntosd-dm320/nsh/defconfig
index 163567e56..ae9f3b6fe 100644
--- a/nuttx/configs/ntosd-dm320/nsh/defconfig
+++ b/nuttx/configs/ntosd-dm320/nsh/defconfig
@@ -397,8 +397,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -421,6 +419,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ntosd-dm320/poll/defconfig b/nuttx/configs/ntosd-dm320/poll/defconfig
index 0f43c2272..d8769f561 100644
--- a/nuttx/configs/ntosd-dm320/poll/defconfig
+++ b/nuttx/configs/ntosd-dm320/poll/defconfig
@@ -390,8 +390,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -410,6 +408,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ntosd-dm320/thttpd/defconfig b/nuttx/configs/ntosd-dm320/thttpd/defconfig
index 7308ed851..2a73e1054 100644
--- a/nuttx/configs/ntosd-dm320/thttpd/defconfig
+++ b/nuttx/configs/ntosd-dm320/thttpd/defconfig
@@ -389,8 +389,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -409,6 +407,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/ntosd-dm320/uip/defconfig b/nuttx/configs/ntosd-dm320/uip/defconfig
index 269d1cfa7..8642a8d9d 100644
--- a/nuttx/configs/ntosd-dm320/uip/defconfig
+++ b/nuttx/configs/ntosd-dm320/uip/defconfig
@@ -389,8 +389,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -409,6 +407,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/olimex-lpc1766stk/ftpc/defconfig b/nuttx/configs/olimex-lpc1766stk/ftpc/defconfig
index 3c4a1afa4..301f34271 100644
--- a/nuttx/configs/olimex-lpc1766stk/ftpc/defconfig
+++ b/nuttx/configs/olimex-lpc1766stk/ftpc/defconfig
@@ -515,8 +515,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=550
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -539,6 +537,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=550
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/olimex-lpc1766stk/hidmouse/defconfig b/nuttx/configs/olimex-lpc1766stk/hidmouse/defconfig
index 21c315b80..507a7bd2f 100644
--- a/nuttx/configs/olimex-lpc1766stk/hidmouse/defconfig
+++ b/nuttx/configs/olimex-lpc1766stk/hidmouse/defconfig
@@ -506,8 +506,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -531,6 +529,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/olimex-lpc1766stk/nettest/defconfig b/nuttx/configs/olimex-lpc1766stk/nettest/defconfig
index f07449121..6e66d4732 100644
--- a/nuttx/configs/olimex-lpc1766stk/nettest/defconfig
+++ b/nuttx/configs/olimex-lpc1766stk/nettest/defconfig
@@ -485,8 +485,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -505,6 +503,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/olimex-lpc1766stk/nsh/defconfig b/nuttx/configs/olimex-lpc1766stk/nsh/defconfig
index e444a6d67..d9033a4c7 100644
--- a/nuttx/configs/olimex-lpc1766stk/nsh/defconfig
+++ b/nuttx/configs/olimex-lpc1766stk/nsh/defconfig
@@ -515,8 +515,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -540,6 +538,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/olimex-lpc1766stk/slip-httpd/defconfig b/nuttx/configs/olimex-lpc1766stk/slip-httpd/defconfig
index 13b1f529c..b9ead68ec 100644
--- a/nuttx/configs/olimex-lpc1766stk/slip-httpd/defconfig
+++ b/nuttx/configs/olimex-lpc1766stk/slip-httpd/defconfig
@@ -465,8 +465,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=256
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -485,6 +483,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=256
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 CONFIG_SLIP_NINTERFACES=1
 CONFIG_SLIP_STACKSIZE=2048
diff --git a/nuttx/configs/olimex-lpc1766stk/thttpd/defconfig b/nuttx/configs/olimex-lpc1766stk/thttpd/defconfig
index f04e98e9c..4be3b0cf0 100644
--- a/nuttx/configs/olimex-lpc1766stk/thttpd/defconfig
+++ b/nuttx/configs/olimex-lpc1766stk/thttpd/defconfig
@@ -485,8 +485,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -505,6 +503,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/olimex-lpc1766stk/zmodem/defconfig b/nuttx/configs/olimex-lpc1766stk/zmodem/defconfig
index ce5da73d6..321cdeaee 100644
--- a/nuttx/configs/olimex-lpc1766stk/zmodem/defconfig
+++ b/nuttx/configs/olimex-lpc1766stk/zmodem/defconfig
@@ -529,8 +529,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -554,6 +552,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/olimex-stm32-p107/nsh/defconfig b/nuttx/configs/olimex-stm32-p107/nsh/defconfig
index cbd4af0fe..96f67a5a1 100644
--- a/nuttx/configs/olimex-stm32-p107/nsh/defconfig
+++ b/nuttx/configs/olimex-stm32-p107/nsh/defconfig
@@ -513,8 +513,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=624
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
 # CONFIG_NET_TCP_SPLIT is not set
@@ -534,6 +532,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=624
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 
 #
 # File Systems
diff --git a/nuttx/configs/olimex-stm32-p207/nsh/defconfig b/nuttx/configs/olimex-stm32-p207/nsh/defconfig
index 71ee3a9a2..9f43d37d9 100644
--- a/nuttx/configs/olimex-stm32-p207/nsh/defconfig
+++ b/nuttx/configs/olimex-stm32-p207/nsh/defconfig
@@ -550,8 +550,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=20
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
 # CONFIG_NET_TCP_SPLIT is not set
@@ -572,6 +570,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 
 #
 # File Systems
diff --git a/nuttx/configs/olimex-strp711/nettest/defconfig b/nuttx/configs/olimex-strp711/nettest/defconfig
index c4dc098d5..0c24a0f40 100644
--- a/nuttx/configs/olimex-strp711/nettest/defconfig
+++ b/nuttx/configs/olimex-strp711/nettest/defconfig
@@ -411,8 +411,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -431,6 +429,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/pic32-starterkit/nsh2/defconfig b/nuttx/configs/pic32-starterkit/nsh2/defconfig
index a171003c6..cf0fc455a 100644
--- a/nuttx/configs/pic32-starterkit/nsh2/defconfig
+++ b/nuttx/configs/pic32-starterkit/nsh2/defconfig
@@ -553,8 +553,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -577,6 +575,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/pic32mx7mmb/nsh/defconfig b/nuttx/configs/pic32mx7mmb/nsh/defconfig
index 9fc6dadff..83b39d98b 100644
--- a/nuttx/configs/pic32mx7mmb/nsh/defconfig
+++ b/nuttx/configs/pic32mx7mmb/nsh/defconfig
@@ -606,8 +606,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -630,6 +628,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/rgmp/arm/default/defconfig b/nuttx/configs/rgmp/arm/default/defconfig
index a0b63bc04..ba309aff3 100644
--- a/nuttx/configs/rgmp/arm/default/defconfig
+++ b/nuttx/configs/rgmp/arm/default/defconfig
@@ -312,8 +312,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=1460
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -336,6 +334,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=1460
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/rgmp/arm/nsh/defconfig b/nuttx/configs/rgmp/arm/nsh/defconfig
index cc5c92aa4..dea6ce875 100644
--- a/nuttx/configs/rgmp/arm/nsh/defconfig
+++ b/nuttx/configs/rgmp/arm/nsh/defconfig
@@ -334,8 +334,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=1460
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -358,6 +356,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=1460
 CONFIG_NET_ARPTAB_SIZE=8
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/rgmp/x86/cxxtest/defconfig b/nuttx/configs/rgmp/x86/cxxtest/defconfig
index ed7ce4dd1..7fcc74b28 100644
--- a/nuttx/configs/rgmp/x86/cxxtest/defconfig
+++ b/nuttx/configs/rgmp/x86/cxxtest/defconfig
@@ -341,8 +341,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=1460
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -365,6 +363,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=1460
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/rgmp/x86/default/defconfig b/nuttx/configs/rgmp/x86/default/defconfig
index d882b8cf6..9ea922f01 100644
--- a/nuttx/configs/rgmp/x86/default/defconfig
+++ b/nuttx/configs/rgmp/x86/default/defconfig
@@ -320,8 +320,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=1460
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -344,6 +342,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=1460
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/rgmp/x86/helloxx/defconfig b/nuttx/configs/rgmp/x86/helloxx/defconfig
index 616cfbcba..312b31839 100644
--- a/nuttx/configs/rgmp/x86/helloxx/defconfig
+++ b/nuttx/configs/rgmp/x86/helloxx/defconfig
@@ -341,8 +341,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=1460
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -365,6 +363,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=1460
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/rgmp/x86/nsh/defconfig b/nuttx/configs/rgmp/x86/nsh/defconfig
index 429bb9a48..a455b18ec 100644
--- a/nuttx/configs/rgmp/x86/nsh/defconfig
+++ b/nuttx/configs/rgmp/x86/nsh/defconfig
@@ -342,8 +342,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=1460
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -366,6 +364,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=1460
 CONFIG_NET_ARPTAB_SIZE=8
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/sam4e-ek/nsh/defconfig b/nuttx/configs/sam4e-ek/nsh/defconfig
index e16d92c83..111edc99a 100644
--- a/nuttx/configs/sam4e-ek/nsh/defconfig
+++ b/nuttx/configs/sam4e-ek/nsh/defconfig
@@ -584,8 +584,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=16
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -608,6 +606,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/sam4e-ek/usbnsh/defconfig b/nuttx/configs/sam4e-ek/usbnsh/defconfig
index f3d67290d..1324d549f 100644
--- a/nuttx/configs/sam4e-ek/usbnsh/defconfig
+++ b/nuttx/configs/sam4e-ek/usbnsh/defconfig
@@ -630,8 +630,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=16
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -654,6 +652,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/shenzhou/nsh/defconfig b/nuttx/configs/shenzhou/nsh/defconfig
index 8ff61a9a1..ee442559e 100644
--- a/nuttx/configs/shenzhou/nsh/defconfig
+++ b/nuttx/configs/shenzhou/nsh/defconfig
@@ -404,8 +404,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
 CONFIG_NET_UDP=y
@@ -420,6 +418,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 
 #
 # File Systems
diff --git a/nuttx/configs/shenzhou/nxwm/defconfig b/nuttx/configs/shenzhou/nxwm/defconfig
index 5179d010f..4a4df03ed 100644
--- a/nuttx/configs/shenzhou/nxwm/defconfig
+++ b/nuttx/configs/shenzhou/nxwm/defconfig
@@ -623,8 +623,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=16
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=4
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
 # CONFIG_NET_TCP_SPLIT is not set
@@ -646,6 +644,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/shenzhou/thttpd/defconfig b/nuttx/configs/shenzhou/thttpd/defconfig
index 03cada392..3c13c9ddf 100644
--- a/nuttx/configs/shenzhou/thttpd/defconfig
+++ b/nuttx/configs/shenzhou/thttpd/defconfig
@@ -391,8 +391,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=742
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
 CONFIG_NET_UDP=y
@@ -407,6 +405,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=742
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 
 #
 # File Systems
diff --git a/nuttx/configs/sim/nettest/defconfig b/nuttx/configs/sim/nettest/defconfig
index bcbd3b2b9..01963df63 100644
--- a/nuttx/configs/sim/nettest/defconfig
+++ b/nuttx/configs/sim/nettest/defconfig
@@ -296,8 +296,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -316,6 +314,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3220g-eval/nettest/defconfig b/nuttx/configs/stm3220g-eval/nettest/defconfig
index fcdb162e0..99f5516e8 100644
--- a/nuttx/configs/stm3220g-eval/nettest/defconfig
+++ b/nuttx/configs/stm3220g-eval/nettest/defconfig
@@ -591,8 +591,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -611,6 +609,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3220g-eval/nsh/defconfig b/nuttx/configs/stm3220g-eval/nsh/defconfig
index 09aeb18a9..5893e747d 100644
--- a/nuttx/configs/stm3220g-eval/nsh/defconfig
+++ b/nuttx/configs/stm3220g-eval/nsh/defconfig
@@ -635,8 +635,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -659,6 +657,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3220g-eval/nsh2/defconfig b/nuttx/configs/stm3220g-eval/nsh2/defconfig
index f66fe5a1a..88ed24d93 100644
--- a/nuttx/configs/stm3220g-eval/nsh2/defconfig
+++ b/nuttx/configs/stm3220g-eval/nsh2/defconfig
@@ -638,8 +638,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -662,6 +660,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3220g-eval/nxwm/defconfig b/nuttx/configs/stm3220g-eval/nxwm/defconfig
index d15e31176..15095a5a8 100644
--- a/nuttx/configs/stm3220g-eval/nxwm/defconfig
+++ b/nuttx/configs/stm3220g-eval/nxwm/defconfig
@@ -670,8 +670,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -694,6 +692,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3220g-eval/telnetd/defconfig b/nuttx/configs/stm3220g-eval/telnetd/defconfig
index c173ac3ca..33bca8973 100644
--- a/nuttx/configs/stm3220g-eval/telnetd/defconfig
+++ b/nuttx/configs/stm3220g-eval/telnetd/defconfig
@@ -591,8 +591,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -611,6 +609,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3240g-eval/discover/defconfig b/nuttx/configs/stm3240g-eval/discover/defconfig
index 248eb5792..002fc48c5 100644
--- a/nuttx/configs/stm3240g-eval/discover/defconfig
+++ b/nuttx/configs/stm3240g-eval/discover/defconfig
@@ -631,8 +631,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=624
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -655,6 +653,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=624
 CONFIG_NET_ARPTAB_SIZE=16
 CONFIG_NET_ARP_IPIN=y
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3240g-eval/nettest/defconfig b/nuttx/configs/stm3240g-eval/nettest/defconfig
index 7104b0046..40b6d4e46 100644
--- a/nuttx/configs/stm3240g-eval/nettest/defconfig
+++ b/nuttx/configs/stm3240g-eval/nettest/defconfig
@@ -593,8 +593,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -613,6 +611,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3240g-eval/nsh/defconfig b/nuttx/configs/stm3240g-eval/nsh/defconfig
index 89f0e3573..a42a7b8eb 100644
--- a/nuttx/configs/stm3240g-eval/nsh/defconfig
+++ b/nuttx/configs/stm3240g-eval/nsh/defconfig
@@ -616,8 +616,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -640,6 +638,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3240g-eval/nsh2/defconfig b/nuttx/configs/stm3240g-eval/nsh2/defconfig
index 1701faa20..01e2963d6 100644
--- a/nuttx/configs/stm3240g-eval/nsh2/defconfig
+++ b/nuttx/configs/stm3240g-eval/nsh2/defconfig
@@ -640,8 +640,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -664,6 +662,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3240g-eval/nxconsole/defconfig b/nuttx/configs/stm3240g-eval/nxconsole/defconfig
index 0ee0b0a50..cd5c0260d 100644
--- a/nuttx/configs/stm3240g-eval/nxconsole/defconfig
+++ b/nuttx/configs/stm3240g-eval/nxconsole/defconfig
@@ -647,8 +647,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -671,6 +669,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3240g-eval/nxwm/defconfig b/nuttx/configs/stm3240g-eval/nxwm/defconfig
index efa8c44e6..b0637eada 100644
--- a/nuttx/configs/stm3240g-eval/nxwm/defconfig
+++ b/nuttx/configs/stm3240g-eval/nxwm/defconfig
@@ -665,8 +665,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -689,6 +687,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3240g-eval/telnetd/defconfig b/nuttx/configs/stm3240g-eval/telnetd/defconfig
index 60df903b9..d3968671d 100644
--- a/nuttx/configs/stm3240g-eval/telnetd/defconfig
+++ b/nuttx/configs/stm3240g-eval/telnetd/defconfig
@@ -593,8 +593,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -613,6 +611,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3240g-eval/webserver/defconfig b/nuttx/configs/stm3240g-eval/webserver/defconfig
index 6b0fa2442..468156298 100644
--- a/nuttx/configs/stm3240g-eval/webserver/defconfig
+++ b/nuttx/configs/stm3240g-eval/webserver/defconfig
@@ -630,8 +630,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -654,6 +652,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/stm3240g-eval/xmlrpc/defconfig b/nuttx/configs/stm3240g-eval/xmlrpc/defconfig
index ba015dcba..7bdd1e7b1 100644
--- a/nuttx/configs/stm3240g-eval/xmlrpc/defconfig
+++ b/nuttx/configs/stm3240g-eval/xmlrpc/defconfig
@@ -626,8 +626,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -650,6 +648,11 @@ CONFIG_NET_STATISTICS=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 CONFIG_NET_ARP_IPIN=y
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/viewtool-stm32f107/netnsh/defconfig b/nuttx/configs/viewtool-stm32f107/netnsh/defconfig
index 3a32331b6..e4f0bcfaf 100644
--- a/nuttx/configs/viewtool-stm32f107/netnsh/defconfig
+++ b/nuttx/configs/viewtool-stm32f107/netnsh/defconfig
@@ -581,8 +581,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=40
 CONFIG_NET_MAX_LISTENPORTS=40
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=624
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -605,6 +603,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=624
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/zkit-arm-1769/hello/defconfig b/nuttx/configs/zkit-arm-1769/hello/defconfig
index 9495b1322..2a6d23b1d 100644
--- a/nuttx/configs/zkit-arm-1769/hello/defconfig
+++ b/nuttx/configs/zkit-arm-1769/hello/defconfig
@@ -485,8 +485,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -505,6 +503,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/zkit-arm-1769/nsh/defconfig b/nuttx/configs/zkit-arm-1769/nsh/defconfig
index 040fe00fa..ae11539e9 100644
--- a/nuttx/configs/zkit-arm-1769/nsh/defconfig
+++ b/nuttx/configs/zkit-arm-1769/nsh/defconfig
@@ -515,8 +515,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -540,6 +538,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/zkit-arm-1769/nxhello/defconfig b/nuttx/configs/zkit-arm-1769/nxhello/defconfig
index acbf63c84..abd30fa99 100644
--- a/nuttx/configs/zkit-arm-1769/nxhello/defconfig
+++ b/nuttx/configs/zkit-arm-1769/nxhello/defconfig
@@ -553,8 +553,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=8
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=16
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 # CONFIG_NET_TCPBACKLOG is not set
@@ -578,6 +576,11 @@ CONFIG_NET_ICMP_PING=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #
diff --git a/nuttx/configs/zkit-arm-1769/thttpd/defconfig b/nuttx/configs/zkit-arm-1769/thttpd/defconfig
index 48c1a8705..50599cee1 100644
--- a/nuttx/configs/zkit-arm-1769/thttpd/defconfig
+++ b/nuttx/configs/zkit-arm-1769/thttpd/defconfig
@@ -485,8 +485,6 @@ CONFIG_NET_TCP=y
 CONFIG_NET_TCP_CONNS=16
 CONFIG_NET_MAX_LISTENPORTS=8
 CONFIG_NET_TCP_READAHEAD=y
-CONFIG_NET_TCP_READAHEAD_BUFSIZE=536
-CONFIG_NET_NTCP_READAHEAD_BUFFERS=8
 # CONFIG_NET_TCP_WRITE_BUFFERS is not set
 CONFIG_NET_TCP_RECVDELAY=0
 CONFIG_NET_TCPBACKLOG=y
@@ -505,6 +503,11 @@ CONFIG_NET_ICMP=y
 CONFIG_NET_RECEIVE_WINDOW=536
 CONFIG_NET_ARPTAB_SIZE=16
 # CONFIG_NET_ARP_IPIN is not set
+CONFIG_NET_IOB=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_BUFSIZE=196
+CONFIG_IOB_NCHAINS=8
+CONFIG_IOB_THROTTLE=0
 # CONFIG_NET_ROUTE is not set
 
 #