2 # Network configuration
8 bool "Networking support"
10 Unless you really know what you are doing, you should say Y here.
11 The reason is that some programs need kernel networking support even
12 when running on a stand-alone machine that isn't connected to any
15 If you are upgrading from an older kernel, you
16 should consider updating your networking tools too because changes
17 in the kernel and the tools often go hand in hand. The tools are
18 contained in the package net-tools, the location and version number
19 of which are given in <file:Documentation/Changes>.
21 For a general introduction to Linux networking, it is highly
22 recommended to read the NET-HOWTO, available from
23 <http://www.tldp.org/docs.html#howto>.
25 # Make sure that all config symbols are dependent on NET
28 menu "Networking options"
31 bool "Network namespace support"
33 depends on EXPERIMENTAL && !SYSFS
35 Allow user space to create what appear to be multiple instances
38 source "net/packet/Kconfig"
39 source "net/unix/Kconfig"
40 source "net/xfrm/Kconfig"
41 source "net/iucv/Kconfig"
44 bool "TCP/IP networking"
46 These are the protocols used on the Internet and on most local
47 Ethernets. It is highly recommended to say Y here (this will enlarge
48 your kernel by about 144 KB), since some programs (e.g. the X window
49 system) use TCP/IP even if your machine is not connected to any
50 other computer. You will get the so-called loopback device which
51 allows you to ping yourself (great fun, that!).
53 For an excellent introduction to Linux networking, please read the
54 Linux Networking HOWTO, available from
55 <http://www.tldp.org/docs.html#howto>.
57 If you say Y here and also to "/proc file system support" and
58 "Sysctl support" below, you can change various aspects of the
59 behavior of the TCP/IP code by writing to the (virtual) files in
60 /proc/sys/net/ipv4/*; the options are explained in the file
61 <file:Documentation/networking/ip-sysctl.txt>.
66 source "net/ipv4/Kconfig"
67 source "net/ipv6/Kconfig"
68 source "net/netlabel/Kconfig"
72 config NETWORK_SECMARK
73 bool "Security Marking"
75 This enables security marking of network packets, similar
76 to nfmark, but designated for security purposes.
77 If you are unsure how to answer this question, answer N.
80 bool "Network packet filtering framework (Netfilter)"
82 Netfilter is a framework for filtering and mangling network packets
83 that pass through your Linux box.
85 The most common use of packet filtering is to run your Linux box as
86 a firewall protecting a local network from the Internet. The type of
87 firewall provided by this kernel support is called a "packet
88 filter", which means that it can reject individual network packets
89 based on type, source, destination etc. The other kind of firewall,
90 a "proxy-based" one, is more secure but more intrusive and more
91 bothersome to set up; it inspects the network traffic much more
92 closely, modifies it and has knowledge about the higher level
93 protocols, which a packet filter lacks. Moreover, proxy-based
94 firewalls often require changes to the programs running on the local
95 clients. Proxy-based firewalls don't need support by the kernel, but
96 they are often combined with a packet filter, which only works if
99 You should also say Y here if you intend to use your Linux box as
100 the gateway to the Internet for a local network of machines without
101 globally valid IP addresses. This is called "masquerading": if one
102 of the computers on your local network wants to send something to
103 the outside, your box can "masquerade" as that computer, i.e. it
104 forwards the traffic to the intended outside destination, but
105 modifies the packets to make it look like they came from the
106 firewall box itself. It works both ways: if the outside host
107 replies, the Linux box will silently forward the traffic to the
108 correct local computer. This way, the computers on your local net
109 are completely invisible to the outside world, even though they can
110 reach the outside and can receive replies. It is even possible to
111 run globally visible servers from within a masqueraded local network
112 using a mechanism called portforwarding. Masquerading is also often
113 called NAT (Network Address Translation).
115 Another use of Netfilter is in transparent proxying: if a machine on
116 the local network tries to connect to an outside host, your Linux
117 box can transparently forward the traffic to a local server,
118 typically a caching proxy server.
120 Yet another use of Netfilter is building a bridging firewall. Using
121 a bridge with Network packet filtering enabled makes iptables "see"
122 the bridged traffic. For filtering on the lower network and Ethernet
123 protocols over the bridge, use ebtables (under bridge netfilter
126 Various modules exist for netfilter which replace the previous
127 masquerading (ipmasqadm), packet filtering (ipchains), transparent
128 proxying, and portforwarding mechanisms. Please see
129 <file:Documentation/Changes> under "iptables" for the location of
132 Make sure to say N to "Fast switching" below if you intend to say Y
133 here, as Fast switching currently bypasses netfilter.
135 Chances are that you should say Y here if you compile a kernel which
136 will run as a router and N for regular hosts. If unsure, say N.
140 config NETFILTER_DEBUG
141 bool "Network packet filtering debugging"
144 You can say Y here if you want to get additional messages useful in
145 debugging the netfilter code.
147 config BRIDGE_NETFILTER
148 bool "Bridged IP/ARP packets filtering"
149 depends on BRIDGE && NETFILTER && INET
152 Enabling this option will let arptables resp. iptables see bridged
153 ARP resp. IP traffic. If you want a bridging firewall, you probably
154 want this option enabled.
155 Enabling or disabling this option doesn't enable or disable
160 source "net/netfilter/Kconfig"
161 source "net/ipv4/netfilter/Kconfig"
162 source "net/ipv6/netfilter/Kconfig"
163 source "net/decnet/netfilter/Kconfig"
164 source "net/bridge/netfilter/Kconfig"
168 source "net/dccp/Kconfig"
169 source "net/sctp/Kconfig"
170 source "net/tipc/Kconfig"
171 source "net/atm/Kconfig"
172 source "net/bridge/Kconfig"
173 source "net/8021q/Kconfig"
174 source "net/decnet/Kconfig"
175 source "net/llc/Kconfig"
176 source "net/ipx/Kconfig"
177 source "drivers/net/appletalk/Kconfig"
178 source "net/x25/Kconfig"
179 source "net/lapb/Kconfig"
180 source "net/econet/Kconfig"
181 source "net/wanrouter/Kconfig"
182 source "net/sched/Kconfig"
184 menu "Network testing"
187 tristate "Packet Generator (USE WITH CAUTION)"
190 This module will inject preconfigured packets, at a configurable
191 rate, out of a given interface. It is used for network interface
192 stress testing and performance analysis. If you don't understand
193 what was just said, you don't need it: say N.
195 Documentation on how to use the packet generator can be found
196 at <file:Documentation/networking/pktgen.txt>.
198 To compile this code as a module, choose M here: the
199 module will be called pktgen.
202 tristate "TCP connection probing"
203 depends on INET && EXPERIMENTAL && PROC_FS && KPROBES
205 This module allows for capturing the changes to TCP connection
206 state in response to incoming packets. It is used for debugging
207 TCP congestion avoidance modules. If you don't understand
208 what was just said, you don't need it: say N.
210 Documentation on how to use TCP connection probing can be found
211 at http://linux-net.osdl.org/index.php/TcpProbe
213 To compile this code as a module, choose M here: the
214 module will be called tcp_probe.
220 source "net/ax25/Kconfig"
221 source "net/irda/Kconfig"
222 source "net/bluetooth/Kconfig"
223 source "net/rxrpc/Kconfig"
231 source "net/wireless/Kconfig"
232 source "net/mac80211/Kconfig"
233 source "net/ieee80211/Kconfig"
237 source "net/rfkill/Kconfig"
238 source "net/9p/Kconfig"