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 packet debugging"
33 You can say Y here if you want to get additional messages useful in
34 debugging bad packets, but can overwhelm logs under denial of service
37 source "net/packet/Kconfig"
38 source "net/unix/Kconfig"
39 source "net/xfrm/Kconfig"
42 bool "TCP/IP networking"
44 These are the protocols used on the Internet and on most local
45 Ethernets. It is highly recommended to say Y here (this will enlarge
46 your kernel by about 144 KB), since some programs (e.g. the X window
47 system) use TCP/IP even if your machine is not connected to any
48 other computer. You will get the so-called loopback device which
49 allows you to ping yourself (great fun, that!).
51 For an excellent introduction to Linux networking, please read the
52 Linux Networking HOWTO, available from
53 <http://www.tldp.org/docs.html#howto>.
55 If you say Y here and also to "/proc file system support" and
56 "Sysctl support" below, you can change various aspects of the
57 behavior of the TCP/IP code by writing to the (virtual) files in
58 /proc/sys/net/ipv4/*; the options are explained in the file
59 <file:Documentation/networking/ip-sysctl.txt>.
64 source "net/ipv4/Kconfig"
65 source "net/ipv6/Kconfig"
70 bool "Network packet filtering (replaces ipchains)"
72 Netfilter is a framework for filtering and mangling network packets
73 that pass through your Linux box.
75 The most common use of packet filtering is to run your Linux box as
76 a firewall protecting a local network from the Internet. The type of
77 firewall provided by this kernel support is called a "packet
78 filter", which means that it can reject individual network packets
79 based on type, source, destination etc. The other kind of firewall,
80 a "proxy-based" one, is more secure but more intrusive and more
81 bothersome to set up; it inspects the network traffic much more
82 closely, modifies it and has knowledge about the higher level
83 protocols, which a packet filter lacks. Moreover, proxy-based
84 firewalls often require changes to the programs running on the local
85 clients. Proxy-based firewalls don't need support by the kernel, but
86 they are often combined with a packet filter, which only works if
89 You should also say Y here if you intend to use your Linux box as
90 the gateway to the Internet for a local network of machines without
91 globally valid IP addresses. This is called "masquerading": if one
92 of the computers on your local network wants to send something to
93 the outside, your box can "masquerade" as that computer, i.e. it
94 forwards the traffic to the intended outside destination, but
95 modifies the packets to make it look like they came from the
96 firewall box itself. It works both ways: if the outside host
97 replies, the Linux box will silently forward the traffic to the
98 correct local computer. This way, the computers on your local net
99 are completely invisible to the outside world, even though they can
100 reach the outside and can receive replies. It is even possible to
101 run globally visible servers from within a masqueraded local network
102 using a mechanism called portforwarding. Masquerading is also often
103 called NAT (Network Address Translation).
105 Another use of Netfilter is in transparent proxying: if a machine on
106 the local network tries to connect to an outside host, your Linux
107 box can transparently forward the traffic to a local server,
108 typically a caching proxy server.
110 Yet another use of Netfilter is building a bridging firewall. Using
111 a bridge with Network packet filtering enabled makes iptables "see"
112 the bridged traffic. For filtering on the lower network and Ethernet
113 protocols over the bridge, use ebtables (under bridge netfilter
116 Various modules exist for netfilter which replace the previous
117 masquerading (ipmasqadm), packet filtering (ipchains), transparent
118 proxying, and portforwarding mechanisms. Please see
119 <file:Documentation/Changes> under "iptables" for the location of
122 Make sure to say N to "Fast switching" below if you intend to say Y
123 here, as Fast switching currently bypasses netfilter.
125 Chances are that you should say Y here if you compile a kernel which
126 will run as a router and N for regular hosts. If unsure, say N.
130 config NETFILTER_DEBUG
131 bool "Network packet filtering debugging"
134 You can say Y here if you want to get additional messages useful in
135 debugging the netfilter code.
137 config BRIDGE_NETFILTER
138 bool "Bridged IP/ARP packets filtering"
139 depends on BRIDGE && NETFILTER && INET
142 Enabling this option will let arptables resp. iptables see bridged
143 ARP resp. IP traffic. If you want a bridging firewall, you probably
144 want this option enabled.
145 Enabling or disabling this option doesn't enable or disable
150 source "net/netfilter/Kconfig"
151 source "net/ipv4/netfilter/Kconfig"
152 source "net/ipv6/netfilter/Kconfig"
153 source "net/decnet/netfilter/Kconfig"
154 source "net/bridge/netfilter/Kconfig"
157 tristate "PlanetLab Virtualized NETwork access"
158 depends on IP_NF_CONNTRACK
160 VNET associates IP connections with VServer virtual contexts
161 and ensures that unprivileged contexts can receive only packets
162 related to connections initiated by, or bound to, sockets
163 created in their contexts.
165 For now, enabling or disabling this option does not compile
166 the driver or activate any non-default code paths. Compile
167 and load the VNET module separately.
173 source "net/dccp/Kconfig"
174 source "net/sctp/Kconfig"
175 source "net/tipc/Kconfig"
176 source "net/atm/Kconfig"
177 source "net/bridge/Kconfig"
178 source "net/8021q/Kconfig"
179 source "net/decnet/Kconfig"
180 source "net/llc/Kconfig"
181 source "net/ipx/Kconfig"
182 source "drivers/net/appletalk/Kconfig"
183 source "net/x25/Kconfig"
184 source "net/lapb/Kconfig"
187 bool "Frame Diverter (EXPERIMENTAL)"
188 depends on EXPERIMENTAL
190 The Frame Diverter allows you to divert packets from the
191 network, that are not aimed at the interface receiving it (in
192 promisc. mode). Typically, a Linux box setup as an Ethernet bridge
193 with the Frames Diverter on, can do some *really* transparent www
194 caching using a Squid proxy for example.
196 This is very useful when you don't want to change your router's
197 config (or if you simply don't have access to it).
199 The other possible usages of diverting Ethernet Frames are
201 - reroute smtp traffic to another interface
202 - traffic-shape certain network streams
203 - transparently proxy smtp connections
206 For more informations, please refer to:
207 <http://diverter.sourceforge.net/>
208 <http://perso.wanadoo.fr/magpie/EtherDivert.html>
212 source "net/econet/Kconfig"
213 source "net/wanrouter/Kconfig"
214 source "net/sched/Kconfig"
216 menu "Network testing"
219 tristate "Packet Generator (USE WITH CAUTION)"
222 This module will inject preconfigured packets, at a configurable
223 rate, out of a given interface. It is used for network interface
224 stress testing and performance analysis. If you don't understand
225 what was just said, you don't need it: say N.
227 Documentation on how to use the packet generator can be found
228 at <file:Documentation/networking/pktgen.txt>.
230 To compile this code as a module, choose M here: the
231 module will be called pktgen.
237 source "net/ax25/Kconfig"
238 source "net/irda/Kconfig"
239 source "net/bluetooth/Kconfig"
240 source "net/ieee80211/Kconfig"