| blob | 19880b086e712f4e29932debfdc0b06714fef6e7 |
1 #
2 # IP configuration
3 #
4 config IP_MULTICAST
5 bool "IP: multicasting"
6 help
7 This is code for addressing several networked computers at once,
8 enlarging your kernel by about 2 KB. You need multicasting if you
9 intend to participate in the MBONE, a high bandwidth network on top
10 of the Internet which carries audio and video broadcasts. More
11 information about the MBONE is on the WWW at
12 <http://www.savetz.com/mbone/>. Information about the multicast
13 capabilities of the various network cards is contained in
14 <file:Documentation/networking/multicast.txt>. For most people, it's
15 safe to say N.
17 config IP_ADVANCED_ROUTER
18 bool "IP: advanced router"
19 ---help---
20 If you intend to run your Linux box mostly as a router, i.e. as a
21 computer that forwards and redistributes network packets, say Y; you
22 will then be presented with several options that allow more precise
23 control about the routing process.
25 The answer to this question won't directly affect the kernel:
26 answering N will just cause the configurator to skip all the
27 questions about advanced routing.
29 Note that your box can only act as a router if you enable IP
30 forwarding in your kernel; you can do that by saying Y to "/proc
31 file system support" and "Sysctl support" below and executing the
32 line
34 echo "1" > /proc/sys/net/ipv4/ip_forward
36 at boot time after the /proc file system has been mounted.
38 If you turn on IP forwarding, you will also get the rp_filter, which
39 automatically rejects incoming packets if the routing table entry
40 for their source address doesn't match the network interface they're
41 arriving on. This has security advantages because it prevents the
42 so-called IP spoofing, however it can pose problems if you use
43 asymmetric routing (packets from you to a host take a different path
44 than packets from that host to you) or if you operate a non-routing
45 host which has several IP addresses on different interfaces. To turn
46 rp_filter on use:
48 echo 1 > /proc/sys/net/ipv4/conf/<device>/rp_filter
49 or
50 echo 1 > /proc/sys/net/ipv4/conf/all/rp_filter
52 If unsure, say N here.
54 choice
55 prompt "Choose IP: FIB lookup algorithm (choose FIB_HASH if unsure)"
56 depends on IP_ADVANCED_ROUTER
57 default ASK_IP_FIB_HASH
59 config ASK_IP_FIB_HASH
60 bool "FIB_HASH"
61 ---help---
62 Current FIB is very proven and good enough for most users.
64 config IP_FIB_TRIE
65 bool "FIB_TRIE"
66 ---help---
67 Use new experimental LC-trie as FIB lookup algorithm.
68 This improves lookup performance if you have a large
69 number of routes.
71 LC-trie is a longest matching prefix lookup algorithm which
72 performs better than FIB_HASH for large routing tables.
73 But, it consumes more memory and is more complex.
75 LC-trie is described in:
77 IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
78 IEEE Journal on Selected Areas in Communications, 17(6):1083-1092, June 1999
79 An experimental study of compression methods for dynamic tries
80 Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
81 http://www.nada.kth.se/~snilsson/public/papers/dyntrie2/
83 endchoice
85 config IP_FIB_HASH
86 def_bool ASK_IP_FIB_HASH || !IP_ADVANCED_ROUTER
88 config IP_FIB_TRIE_STATS
89 bool "FIB TRIE statistics"
90 depends on IP_FIB_TRIE
91 ---help---
92 Keep track of statistics on structure of FIB TRIE table.
93 Useful for testing and measuring TRIE performance.
95 config IP_MULTIPLE_TABLES
96 bool "IP: policy routing"
97 depends on IP_ADVANCED_ROUTER
98 select FIB_RULES
99 ---help---
100 Normally, a router decides what to do with a received packet based
101 solely on the packet's final destination address. If you say Y here,
102 the Linux router will also be able to take the packet's source
103 address into account. Furthermore, the TOS (Type-Of-Service) field
104 of the packet can be used for routing decisions as well.
106 If you are interested in this, please see the preliminary
107 documentation at <http://www.compendium.com.ar/policy-routing.txt>
108 and <ftp://post.tepkom.ru/pub/vol2/Linux/docs/advanced-routing.tex>.
109 You will need supporting software from
110 <ftp://ftp.tux.org/pub/net/ip-routing/>.
112 If unsure, say N.
114 config IP_ROUTE_MULTIPATH
115 bool "IP: equal cost multipath"
116 depends on IP_ADVANCED_ROUTER
117 help
118 Normally, the routing tables specify a single action to be taken in
119 a deterministic manner for a given packet. If you say Y here
120 however, it becomes possible to attach several actions to a packet
121 pattern, in effect specifying several alternative paths to travel
122 for those packets. The router considers all these paths to be of
123 equal "cost" and chooses one of them in a non-deterministic fashion
124 if a matching packet arrives.
126 config IP_ROUTE_VERBOSE
127 bool "IP: verbose route monitoring"
128 depends on IP_ADVANCED_ROUTER
129 help
130 If you say Y here, which is recommended, then the kernel will print
131 verbose messages regarding the routing, for example warnings about
132 received packets which look strange and could be evidence of an
133 attack or a misconfigured system somewhere. The information is
134 handled by the klogd daemon which is responsible for kernel messages
135 ("man klogd").
137 config IP_PNP
138 bool "IP: kernel level autoconfiguration"
139 help
140 This enables automatic configuration of IP addresses of devices and
141 of the routing table during kernel boot, based on either information
142 supplied on the kernel command line or by BOOTP or RARP protocols.
143 You need to say Y only for diskless machines requiring network
144 access to boot (in which case you want to say Y to "Root file system
145 on NFS" as well), because all other machines configure the network
146 in their startup scripts.
148 config IP_PNP_DHCP
149 bool "IP: DHCP support"
150 depends on IP_PNP
151 ---help---
152 If you want your Linux box to mount its whole root file system (the
153 one containing the directory /) from some other computer over the
154 net via NFS and you want the IP address of your computer to be
155 discovered automatically at boot time using the DHCP protocol (a
156 special protocol designed for doing this job), say Y here. In case
157 the boot ROM of your network card was designed for booting Linux and
158 does DHCP itself, providing all necessary information on the kernel
159 command line, you can say N here.
161 If unsure, say Y. Note that if you want to use DHCP, a DHCP server
162 must be operating on your network. Read
163 <file:Documentation/nfsroot.txt> for details.
165 config IP_PNP_BOOTP
166 bool "IP: BOOTP support"
167 depends on IP_PNP
168 ---help---
169 If you want your Linux box to mount its whole root file system (the
170 one containing the directory /) from some other computer over the
171 net via NFS and you want the IP address of your computer to be
172 discovered automatically at boot time using the BOOTP protocol (a
173 special protocol designed for doing this job), say Y here. In case
174 the boot ROM of your network card was designed for booting Linux and
175 does BOOTP itself, providing all necessary information on the kernel
176 command line, you can say N here. If unsure, say Y. Note that if you
177 want to use BOOTP, a BOOTP server must be operating on your network.
178 Read <file:Documentation/nfsroot.txt> for details.
180 config IP_PNP_RARP
181 bool "IP: RARP support"
182 depends on IP_PNP
183 help
184 If you want your Linux box to mount its whole root file system (the
185 one containing the directory /) from some other computer over the
186 net via NFS and you want the IP address of your computer to be
187 discovered automatically at boot time using the RARP protocol (an
188 older protocol which is being obsoleted by BOOTP and DHCP), say Y
189 here. Note that if you want to use RARP, a RARP server must be
190 operating on your network. Read <file:Documentation/nfsroot.txt> for
191 details.
193 # not yet ready..
194 # bool ' IP: ARP support' CONFIG_IP_PNP_ARP
195 config NET_IPIP
196 tristate "IP: tunneling"
197 select INET_TUNNEL
198 ---help---
199 Tunneling means encapsulating data of one protocol type within
200 another protocol and sending it over a channel that understands the
201 encapsulating protocol. This particular tunneling driver implements
202 encapsulation of IP within IP, which sounds kind of pointless, but
203 can be useful if you want to make your (or some other) machine
204 appear on a different network than it physically is, or to use
205 mobile-IP facilities (allowing laptops to seamlessly move between
206 networks without changing their IP addresses).
208 Saying Y to this option will produce two modules ( = code which can
209 be inserted in and removed from the running kernel whenever you
210 want). Most people won't need this and can say N.
212 config NET_IPGRE
213 tristate "IP: GRE tunnels over IP"
214 help
215 Tunneling means encapsulating data of one protocol type within
216 another protocol and sending it over a channel that understands the
217 encapsulating protocol. This particular tunneling driver implements
218 GRE (Generic Routing Encapsulation) and at this time allows
219 encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure.
220 This driver is useful if the other endpoint is a Cisco router: Cisco
221 likes GRE much better than the other Linux tunneling driver ("IP
222 tunneling" above). In addition, GRE allows multicast redistribution
223 through the tunnel.
225 config NET_IPGRE_BROADCAST
226 bool "IP: broadcast GRE over IP"
227 depends on IP_MULTICAST && NET_IPGRE
228 help
229 One application of GRE/IP is to construct a broadcast WAN (Wide Area
230 Network), which looks like a normal Ethernet LAN (Local Area
231 Network), but can be distributed all over the Internet. If you want
232 to do that, say Y here and to "IP multicast routing" below.
234 config IP_MROUTE
235 bool "IP: multicast routing"
236 depends on IP_MULTICAST
237 help
238 This is used if you want your machine to act as a router for IP
239 packets that have several destination addresses. It is needed on the
240 MBONE, a high bandwidth network on top of the Internet which carries
241 audio and video broadcasts. In order to do that, you would most
242 likely run the program mrouted. Information about the multicast
243 capabilities of the various network cards is contained in
244 <file:Documentation/networking/multicast.txt>. If you haven't heard
245 about it, you don't need it.
247 config IP_PIMSM_V1
248 bool "IP: PIM-SM version 1 support"
249 depends on IP_MROUTE
250 help
251 Kernel side support for Sparse Mode PIM (Protocol Independent
252 Multicast) version 1. This multicast routing protocol is used widely
253 because Cisco supports it. You need special software to use it
254 (pimd-v1). Please see <http://netweb.usc.edu/pim/> for more
255 information about PIM.
257 Say Y if you want to use PIM-SM v1. Note that you can say N here if
258 you just want to use Dense Mode PIM.
260 config IP_PIMSM_V2
261 bool "IP: PIM-SM version 2 support"
262 depends on IP_MROUTE
263 help
264 Kernel side support for Sparse Mode PIM version 2. In order to use
265 this, you need an experimental routing daemon supporting it (pimd or
266 gated-5). This routing protocol is not used widely, so say N unless
267 you want to play with it.
269 config ARPD
270 bool "IP: ARP daemon support (EXPERIMENTAL)"
271 depends on EXPERIMENTAL
272 ---help---
273 Normally, the kernel maintains an internal cache which maps IP
274 addresses to hardware addresses on the local network, so that
275 Ethernet/Token Ring/ etc. frames are sent to the proper address on
276 the physical networking layer. For small networks having a few
277 hundred directly connected hosts or less, keeping this address
278 resolution (ARP) cache inside the kernel works well. However,
279 maintaining an internal ARP cache does not work well for very large
280 switched networks, and will use a lot of kernel memory if TCP/IP
281 connections are made to many machines on the network.
283 If you say Y here, the kernel's internal ARP cache will never grow
284 to more than 256 entries (the oldest entries are expired in a LIFO
285 manner) and communication will be attempted with the user space ARP
286 daemon arpd. Arpd then answers the address resolution request either
287 from its own cache or by asking the net.
289 This code is experimental and also obsolete. If you want to use it,
290 you need to find a version of the daemon arpd on the net somewhere,
291 and you should also say Y to "Kernel/User network link driver",
292 below. If unsure, say N.
294 config SYN_COOKIES
295 bool "IP: TCP syncookie support (disabled per default)"
296 ---help---
297 Normal TCP/IP networking is open to an attack known as "SYN
298 flooding". This denial-of-service attack prevents legitimate remote
299 users from being able to connect to your computer during an ongoing
300 attack and requires very little work from the attacker, who can
301 operate from anywhere on the Internet.
303 SYN cookies provide protection against this type of attack. If you
304 say Y here, the TCP/IP stack will use a cryptographic challenge
305 protocol known as "SYN cookies" to enable legitimate users to
306 continue to connect, even when your machine is under attack. There
307 is no need for the legitimate users to change their TCP/IP software;
308 SYN cookies work transparently to them. For technical information
309 about SYN cookies, check out <http://cr.yp.to/syncookies.html>.
311 If you are SYN flooded, the source address reported by the kernel is
312 likely to have been forged by the attacker; it is only reported as
313 an aid in tracing the packets to their actual source and should not
314 be taken as absolute truth.
316 SYN cookies may prevent correct error reporting on clients when the
317 server is really overloaded. If this happens frequently better turn
318 them off.
320 If you say Y here, note that SYN cookies aren't enabled by default;
321 you can enable them by saying Y to "/proc file system support" and
322 "Sysctl support" below and executing the command
324 echo 1 >/proc/sys/net/ipv4/tcp_syncookies
326 at boot time after the /proc file system has been mounted.
328 If unsure, say N.
330 config INET_AH
331 tristate "IP: AH transformation"
332 select XFRM
333 select CRYPTO
334 select CRYPTO_HMAC
335 select CRYPTO_MD5
336 select CRYPTO_SHA1
337 ---help---
338 Support for IPsec AH.
340 If unsure, say Y.
342 config INET_ESP
343 tristate "IP: ESP transformation"
344 select XFRM
345 select CRYPTO
346 select CRYPTO_AEAD
347 select CRYPTO_HMAC
348 select CRYPTO_MD5
349 select CRYPTO_CBC
350 select CRYPTO_SHA1
351 select CRYPTO_DES
352 ---help---
353 Support for IPsec ESP.
355 If unsure, say Y.
357 config INET_IPCOMP
358 tristate "IP: IPComp transformation"
359 select XFRM
360 select INET_XFRM_TUNNEL
361 select CRYPTO
362 select CRYPTO_DEFLATE
363 ---help---
364 Support for IP Payload Compression Protocol (IPComp) (RFC3173),
365 typically needed for IPsec.
367 If unsure, say Y.
369 config INET_XFRM_TUNNEL
370 tristate
371 select INET_TUNNEL
372 default n
374 config INET_TUNNEL
375 tristate
376 default n
378 config INET_XFRM_MODE_TRANSPORT
379 tristate "IP: IPsec transport mode"
380 default y
381 select XFRM
382 ---help---
383 Support for IPsec transport mode.
385 If unsure, say Y.
387 config INET_XFRM_MODE_TUNNEL
388 tristate "IP: IPsec tunnel mode"
389 default y
390 select XFRM
391 ---help---
392 Support for IPsec tunnel mode.
394 If unsure, say Y.
396 config INET_XFRM_MODE_BEET
397 tristate "IP: IPsec BEET mode"
398 default y
399 select XFRM
400 ---help---
401 Support for IPsec BEET mode.
403 If unsure, say Y.
405 config INET_LRO
406 tristate "Large Receive Offload (ipv4/tcp)"
408 ---help---
409 Support for Large Receive Offload (ipv4/tcp).
411 If unsure, say Y.
413 config INET_DIAG
414 tristate "INET: socket monitoring interface"
415 default y
416 ---help---
417 Support for INET (TCP, DCCP, etc) socket monitoring interface used by
418 native Linux tools such as ss. ss is included in iproute2, currently
419 downloadable at <http://linux-net.osdl.org/index.php/Iproute2>.
421 If unsure, say Y.
423 config INET_TCP_DIAG
424 depends on INET_DIAG
425 def_tristate INET_DIAG
427 menuconfig TCP_CONG_ADVANCED
428 bool "TCP: advanced congestion control"
429 ---help---
430 Support for selection of various TCP congestion control
431 modules.
433 Nearly all users can safely say no here, and a safe default
434 selection will be made (CUBIC with new Reno as a fallback).
436 If unsure, say N.
438 if TCP_CONG_ADVANCED
440 config TCP_CONG_BIC
441 tristate "Binary Increase Congestion (BIC) control"
442 default m
443 ---help---
444 BIC-TCP is a sender-side only change that ensures a linear RTT
445 fairness under large windows while offering both scalability and
446 bounded TCP-friendliness. The protocol combines two schemes
447 called additive increase and binary search increase. When the
448 congestion window is large, additive increase with a large
449 increment ensures linear RTT fairness as well as good
450 scalability. Under small congestion windows, binary search
451 increase provides TCP friendliness.
452 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/
454 config TCP_CONG_CUBIC
455 tristate "CUBIC TCP"
456 default y
457 ---help---
458 This is version 2.0 of BIC-TCP which uses a cubic growth function
459 among other techniques.
460 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf
462 config TCP_CONG_WESTWOOD
463 tristate "TCP Westwood+"
464 default m
465 ---help---
466 TCP Westwood+ is a sender-side only modification of the TCP Reno
467 protocol stack that optimizes the performance of TCP congestion
468 control. It is based on end-to-end bandwidth estimation to set
469 congestion window and slow start threshold after a congestion
470 episode. Using this estimation, TCP Westwood+ adaptively sets a
471 slow start threshold and a congestion window which takes into
472 account the bandwidth used at the time congestion is experienced.
473 TCP Westwood+ significantly increases fairness wrt TCP Reno in
474 wired networks and throughput over wireless links.
476 config TCP_CONG_HTCP
477 tristate "H-TCP"
478 default m
479 ---help---
480 H-TCP is a send-side only modifications of the TCP Reno
481 protocol stack that optimizes the performance of TCP
482 congestion control for high speed network links. It uses a
483 modeswitch to change the alpha and beta parameters of TCP Reno
484 based on network conditions and in a way so as to be fair with
485 other Reno and H-TCP flows.
487 config TCP_CONG_HSTCP
488 tristate "High Speed TCP"
489 depends on EXPERIMENTAL
490 default n
491 ---help---
492 Sally Floyd's High Speed TCP (RFC 3649) congestion control.
493 A modification to TCP's congestion control mechanism for use
494 with large congestion windows. A table indicates how much to
495 increase the congestion window by when an ACK is received.
496 For more detail see http://www.icir.org/floyd/hstcp.html
498 config TCP_CONG_HYBLA
499 tristate "TCP-Hybla congestion control algorithm"
500 depends on EXPERIMENTAL
501 default n
502 ---help---
503 TCP-Hybla is a sender-side only change that eliminates penalization of
504 long-RTT, large-bandwidth connections, like when satellite legs are
505 involved, especially when sharing a common bottleneck with normal
506 terrestrial connections.
508 config TCP_CONG_VEGAS
509 tristate "TCP Vegas"
510 depends on EXPERIMENTAL
511 default n
512 ---help---
513 TCP Vegas is a sender-side only change to TCP that anticipates
514 the onset of congestion by estimating the bandwidth. TCP Vegas
515 adjusts the sending rate by modifying the congestion
516 window. TCP Vegas should provide less packet loss, but it is
517 not as aggressive as TCP Reno.
519 config TCP_CONG_SCALABLE
520 tristate "Scalable TCP"
521 depends on EXPERIMENTAL
522 default n
523 ---help---
524 Scalable TCP is a sender-side only change to TCP which uses a
525 MIMD congestion control algorithm which has some nice scaling
526 properties, though is known to have fairness issues.
527 See http://www.deneholme.net/tom/scalable/
529 config TCP_CONG_LP
530 tristate "TCP Low Priority"
531 depends on EXPERIMENTAL
532 default n
533 ---help---
534 TCP Low Priority (TCP-LP), a distributed algorithm whose goal is
535 to utilize only the excess network bandwidth as compared to the
536 ``fair share`` of bandwidth as targeted by TCP.
537 See http://www-ece.rice.edu/networks/TCP-LP/
539 config TCP_CONG_VENO
540 tristate "TCP Veno"
541 depends on EXPERIMENTAL
542 default n
543 ---help---
544 TCP Veno is a sender-side only enhancement of TCP to obtain better
545 throughput over wireless networks. TCP Veno makes use of state
546 distinguishing to circumvent the difficult judgment of the packet loss
547 type. TCP Veno cuts down less congestion window in response to random
548 loss packets.
549 See http://www.ntu.edu.sg/home5/ZHOU0022/papers/CPFu03a.pdf
551 config TCP_CONG_YEAH
552 tristate "YeAH TCP"
553 depends on EXPERIMENTAL
554 select TCP_CONG_VEGAS
555 default n
556 ---help---
557 YeAH-TCP is a sender-side high-speed enabled TCP congestion control
558 algorithm, which uses a mixed loss/delay approach to compute the
559 congestion window. It's design goals target high efficiency,
560 internal, RTT and Reno fairness, resilience to link loss while
561 keeping network elements load as low as possible.
563 For further details look here:
564 http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf
566 config TCP_CONG_ILLINOIS
567 tristate "TCP Illinois"
568 depends on EXPERIMENTAL
569 default n
570 ---help---
571 TCP-Illinois is a sender-side modification of TCP Reno for
572 high speed long delay links. It uses round-trip-time to
573 adjust the alpha and beta parameters to achieve a higher average
574 throughput and maintain fairness.
576 For further details see:
577 http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html
579 choice
580 prompt "Default TCP congestion control"
581 default DEFAULT_CUBIC
582 help
583 Select the TCP congestion control that will be used by default
584 for all connections.
586 config DEFAULT_BIC
587 bool "Bic" if TCP_CONG_BIC=y
589 config DEFAULT_CUBIC
590 bool "Cubic" if TCP_CONG_CUBIC=y
592 config DEFAULT_HTCP
593 bool "Htcp" if TCP_CONG_HTCP=y
595 config DEFAULT_VEGAS
596 bool "Vegas" if TCP_CONG_VEGAS=y
598 config DEFAULT_WESTWOOD
599 bool "Westwood" if TCP_CONG_WESTWOOD=y
601 config DEFAULT_RENO
602 bool "Reno"
604 endchoice
606 endif
608 config TCP_CONG_CUBIC
609 tristate
610 depends on !TCP_CONG_ADVANCED
611 default y
613 config DEFAULT_TCP_CONG
614 string
615 default "bic" if DEFAULT_BIC
616 default "cubic" if DEFAULT_CUBIC
617 default "htcp" if DEFAULT_HTCP
618 default "vegas" if DEFAULT_VEGAS
619 default "westwood" if DEFAULT_WESTWOOD
620 default "reno" if DEFAULT_RENO
621 default "cubic"
623 config TCP_MD5SIG
624 bool "TCP: MD5 Signature Option support (RFC2385) (EXPERIMENTAL)"
625 depends on EXPERIMENTAL
626 select CRYPTO
627 select CRYPTO_MD5
628 ---help---
629 RFC2385 specifies a method of giving MD5 protection to TCP sessions.
630 Its main (only?) use is to protect BGP sessions between core routers
631 on the Internet.
633 If unsure, say N.
635 source "net/ipv4/ipvs/Kconfig"