| blob | 9e95d7fb6d5ac4d3d19db7f3c39117d9908a35e3 |
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 should consider 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 Note that some distributions enable it in startup scripts.
53 For details about rp_filter strict and loose mode read
54 <file:Documentation/networking/ip-sysctl.txt>.
56 If unsure, say N here.
58 choice
59 prompt "Choose IP: FIB lookup algorithm (choose FIB_HASH if unsure)"
60 depends on IP_ADVANCED_ROUTER
61 default ASK_IP_FIB_HASH
63 config ASK_IP_FIB_HASH
64 bool "FIB_HASH"
65 ---help---
66 Current FIB is very proven and good enough for most users.
68 config IP_FIB_TRIE
69 bool "FIB_TRIE"
70 ---help---
71 Use new experimental LC-trie as FIB lookup algorithm.
72 This improves lookup performance if you have a large
73 number of routes.
75 LC-trie is a longest matching prefix lookup algorithm which
76 performs better than FIB_HASH for large routing tables.
77 But, it consumes more memory and is more complex.
79 LC-trie is described in:
81 IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
82 IEEE Journal on Selected Areas in Communications, 17(6):1083-1092,
83 June 1999
85 An experimental study of compression methods for dynamic tries
86 Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
87 <http://www.csc.kth.se/~snilsson/software/dyntrie2/>
89 endchoice
91 config IP_FIB_HASH
92 def_bool ASK_IP_FIB_HASH || !IP_ADVANCED_ROUTER
94 config IP_FIB_TRIE_STATS
95 bool "FIB TRIE statistics"
96 depends on IP_FIB_TRIE
97 ---help---
98 Keep track of statistics on structure of FIB TRIE table.
99 Useful for testing and measuring TRIE performance.
101 config IP_MULTIPLE_TABLES
102 bool "IP: policy routing"
103 depends on IP_ADVANCED_ROUTER
104 select FIB_RULES
105 ---help---
106 Normally, a router decides what to do with a received packet based
107 solely on the packet's final destination address. If you say Y here,
108 the Linux router will also be able to take the packet's source
109 address into account. Furthermore, the TOS (Type-Of-Service) field
110 of the packet can be used for routing decisions as well.
112 If you are interested in this, please see the preliminary
113 documentation at <http://www.compendium.com.ar/policy-routing.txt>
114 and <ftp://post.tepkom.ru/pub/vol2/Linux/docs/advanced-routing.tex>.
115 You will need supporting software from
116 <ftp://ftp.tux.org/pub/net/ip-routing/>.
118 If unsure, say N.
120 config IP_ROUTE_MULTIPATH
121 bool "IP: equal cost multipath"
122 depends on IP_ADVANCED_ROUTER
123 help
124 Normally, the routing tables specify a single action to be taken in
125 a deterministic manner for a given packet. If you say Y here
126 however, it becomes possible to attach several actions to a packet
127 pattern, in effect specifying several alternative paths to travel
128 for those packets. The router considers all these paths to be of
129 equal "cost" and chooses one of them in a non-deterministic fashion
130 if a matching packet arrives.
132 config IP_ROUTE_VERBOSE
133 bool "IP: verbose route monitoring"
134 depends on IP_ADVANCED_ROUTER
135 help
136 If you say Y here, which is recommended, then the kernel will print
137 verbose messages regarding the routing, for example warnings about
138 received packets which look strange and could be evidence of an
139 attack or a misconfigured system somewhere. The information is
140 handled by the klogd daemon which is responsible for kernel messages
141 ("man klogd").
143 config IP_PNP
144 bool "IP: kernel level autoconfiguration"
145 help
146 This enables automatic configuration of IP addresses of devices and
147 of the routing table during kernel boot, based on either information
148 supplied on the kernel command line or by BOOTP or RARP protocols.
149 You need to say Y only for diskless machines requiring network
150 access to boot (in which case you want to say Y to "Root file system
151 on NFS" as well), because all other machines configure the network
152 in their startup scripts.
154 config IP_PNP_DHCP
155 bool "IP: DHCP support"
156 depends on IP_PNP
157 ---help---
158 If you want your Linux box to mount its whole root file system (the
159 one containing the directory /) from some other computer over the
160 net via NFS and you want the IP address of your computer to be
161 discovered automatically at boot time using the DHCP protocol (a
162 special protocol designed for doing this job), say Y here. In case
163 the boot ROM of your network card was designed for booting Linux and
164 does DHCP itself, providing all necessary information on the kernel
165 command line, you can say N here.
167 If unsure, say Y. Note that if you want to use DHCP, a DHCP server
168 must be operating on your network. Read
169 <file:Documentation/filesystems/nfs/nfsroot.txt> for details.
171 config IP_PNP_BOOTP
172 bool "IP: BOOTP support"
173 depends on IP_PNP
174 ---help---
175 If you want your Linux box to mount its whole root file system (the
176 one containing the directory /) from some other computer over the
177 net via NFS and you want the IP address of your computer to be
178 discovered automatically at boot time using the BOOTP protocol (a
179 special protocol designed for doing this job), say Y here. In case
180 the boot ROM of your network card was designed for booting Linux and
181 does BOOTP itself, providing all necessary information on the kernel
182 command line, you can say N here. If unsure, say Y. Note that if you
183 want to use BOOTP, a BOOTP server must be operating on your network.
184 Read <file:Documentation/filesystems/nfs/nfsroot.txt> for details.
186 config IP_PNP_RARP
187 bool "IP: RARP support"
188 depends on IP_PNP
189 help
190 If you want your Linux box to mount its whole root file system (the
191 one containing the directory /) from some other computer over the
192 net via NFS and you want the IP address of your computer to be
193 discovered automatically at boot time using the RARP protocol (an
194 older protocol which is being obsoleted by BOOTP and DHCP), say Y
195 here. Note that if you want to use RARP, a RARP server must be
196 operating on your network. Read
197 <file:Documentation/filesystems/nfs/nfsroot.txt> for details.
199 # not yet ready..
200 # bool ' IP: ARP support' CONFIG_IP_PNP_ARP
201 config NET_IPIP
202 tristate "IP: tunneling"
203 select INET_TUNNEL
204 ---help---
205 Tunneling means encapsulating data of one protocol type within
206 another protocol and sending it over a channel that understands the
207 encapsulating protocol. This particular tunneling driver implements
208 encapsulation of IP within IP, which sounds kind of pointless, but
209 can be useful if you want to make your (or some other) machine
210 appear on a different network than it physically is, or to use
211 mobile-IP facilities (allowing laptops to seamlessly move between
212 networks without changing their IP addresses).
214 Saying Y to this option will produce two modules ( = code which can
215 be inserted in and removed from the running kernel whenever you
216 want). Most people won't need this and can say N.
218 config NET_IPGRE_DEMUX
219 tristate "IP: GRE demultiplexer"
220 help
221 This is helper module to demultiplex GRE packets on GRE version field criteria.
222 Required by ip_gre and pptp modules.
224 config NET_IPGRE
225 tristate "IP: GRE tunnels over IP"
226 depends on (IPV6 || IPV6=n) && NET_IPGRE_DEMUX
227 help
228 Tunneling means encapsulating data of one protocol type within
229 another protocol and sending it over a channel that understands the
230 encapsulating protocol. This particular tunneling driver implements
231 GRE (Generic Routing Encapsulation) and at this time allows
232 encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure.
233 This driver is useful if the other endpoint is a Cisco router: Cisco
234 likes GRE much better than the other Linux tunneling driver ("IP
235 tunneling" above). In addition, GRE allows multicast redistribution
236 through the tunnel.
238 config NET_IPGRE_BROADCAST
239 bool "IP: broadcast GRE over IP"
240 depends on IP_MULTICAST && NET_IPGRE
241 help
242 One application of GRE/IP is to construct a broadcast WAN (Wide Area
243 Network), which looks like a normal Ethernet LAN (Local Area
244 Network), but can be distributed all over the Internet. If you want
245 to do that, say Y here and to "IP multicast routing" below.
247 config IP_MROUTE
248 bool "IP: multicast routing"
249 depends on IP_MULTICAST
250 help
251 This is used if you want your machine to act as a router for IP
252 packets that have several destination addresses. It is needed on the
253 MBONE, a high bandwidth network on top of the Internet which carries
254 audio and video broadcasts. In order to do that, you would most
255 likely run the program mrouted. Information about the multicast
256 capabilities of the various network cards is contained in
257 <file:Documentation/networking/multicast.txt>. If you haven't heard
258 about it, you don't need it.
260 config IP_MROUTE_MULTIPLE_TABLES
261 bool "IP: multicast policy routing"
262 depends on IP_MROUTE && IP_ADVANCED_ROUTER
263 select FIB_RULES
264 help
265 Normally, a multicast router runs a userspace daemon and decides
266 what to do with a multicast packet based on the source and
267 destination addresses. If you say Y here, the multicast router
268 will also be able to take interfaces and packet marks into
269 account and run multiple instances of userspace daemons
270 simultaneously, each one handling a single table.
272 If unsure, say N.
274 config IP_PIMSM_V1
275 bool "IP: PIM-SM version 1 support"
276 depends on IP_MROUTE
277 help
278 Kernel side support for Sparse Mode PIM (Protocol Independent
279 Multicast) version 1. This multicast routing protocol is used widely
280 because Cisco supports it. You need special software to use it
281 (pimd-v1). Please see <http://netweb.usc.edu/pim/> for more
282 information about PIM.
284 Say Y if you want to use PIM-SM v1. Note that you can say N here if
285 you just want to use Dense Mode PIM.
287 config IP_PIMSM_V2
288 bool "IP: PIM-SM version 2 support"
289 depends on IP_MROUTE
290 help
291 Kernel side support for Sparse Mode PIM version 2. In order to use
292 this, you need an experimental routing daemon supporting it (pimd or
293 gated-5). This routing protocol is not used widely, so say N unless
294 you want to play with it.
296 config ARPD
297 bool "IP: ARP daemon support"
298 ---help---
299 The kernel maintains an internal cache which maps IP addresses to
300 hardware addresses on the local network, so that Ethernet/Token Ring/
301 etc. frames are sent to the proper address on the physical networking
302 layer. Normally, kernel uses the ARP protocol to resolve these
303 mappings.
305 Saying Y here adds support to have an user space daemon to do this
306 resolution instead. This is useful for implementing an alternate
307 address resolution protocol (e.g. NHRP on mGRE tunnels) and also for
308 testing purposes.
310 If unsure, say N.
312 config SYN_COOKIES
313 bool "IP: TCP syncookie support"
314 ---help---
315 Normal TCP/IP networking is open to an attack known as "SYN
316 flooding". This denial-of-service attack prevents legitimate remote
317 users from being able to connect to your computer during an ongoing
318 attack and requires very little work from the attacker, who can
319 operate from anywhere on the Internet.
321 SYN cookies provide protection against this type of attack. If you
322 say Y here, the TCP/IP stack will use a cryptographic challenge
323 protocol known as "SYN cookies" to enable legitimate users to
324 continue to connect, even when your machine is under attack. There
325 is no need for the legitimate users to change their TCP/IP software;
326 SYN cookies work transparently to them. For technical information
327 about SYN cookies, check out <http://cr.yp.to/syncookies.html>.
329 If you are SYN flooded, the source address reported by the kernel is
330 likely to have been forged by the attacker; it is only reported as
331 an aid in tracing the packets to their actual source and should not
332 be taken as absolute truth.
334 SYN cookies may prevent correct error reporting on clients when the
335 server is really overloaded. If this happens frequently better turn
336 them off.
338 If you say Y here, you can disable SYN cookies at run time by
339 saying Y to "/proc file system support" and
340 "Sysctl support" below and executing the command
342 echo 0 > /proc/sys/net/ipv4/tcp_syncookies
344 after the /proc file system has been mounted.
346 If unsure, say N.
348 config INET_AH
349 tristate "IP: AH transformation"
350 select XFRM
351 select CRYPTO
352 select CRYPTO_HMAC
353 select CRYPTO_MD5
354 select CRYPTO_SHA1
355 ---help---
356 Support for IPsec AH.
358 If unsure, say Y.
360 config INET_ESP
361 tristate "IP: ESP transformation"
362 select XFRM
363 select CRYPTO
364 select CRYPTO_AUTHENC
365 select CRYPTO_HMAC
366 select CRYPTO_MD5
367 select CRYPTO_CBC
368 select CRYPTO_SHA1
369 select CRYPTO_DES
370 ---help---
371 Support for IPsec ESP.
373 If unsure, say Y.
375 config INET_IPCOMP
376 tristate "IP: IPComp transformation"
377 select INET_XFRM_TUNNEL
378 select XFRM_IPCOMP
379 ---help---
380 Support for IP Payload Compression Protocol (IPComp) (RFC3173),
381 typically needed for IPsec.
383 If unsure, say Y.
385 config INET_XFRM_TUNNEL
386 tristate
387 select INET_TUNNEL
388 default n
390 config INET_TUNNEL
391 tristate
392 default n
394 config INET_XFRM_MODE_TRANSPORT
395 tristate "IP: IPsec transport mode"
396 default y
397 select XFRM
398 ---help---
399 Support for IPsec transport mode.
401 If unsure, say Y.
403 config INET_XFRM_MODE_TUNNEL
404 tristate "IP: IPsec tunnel mode"
405 default y
406 select XFRM
407 ---help---
408 Support for IPsec tunnel mode.
410 If unsure, say Y.
412 config INET_XFRM_MODE_BEET
413 tristate "IP: IPsec BEET mode"
414 default y
415 select XFRM
416 ---help---
417 Support for IPsec BEET mode.
419 If unsure, say Y.
421 config INET_LRO
422 tristate "Large Receive Offload (ipv4/tcp)"
423 default y
424 ---help---
425 Support for Large Receive Offload (ipv4/tcp).
427 If unsure, say Y.
429 config INET_DIAG
430 tristate "INET: socket monitoring interface"
431 default y
432 ---help---
433 Support for INET (TCP, DCCP, etc) socket monitoring interface used by
434 native Linux tools such as ss. ss is included in iproute2, currently
435 downloadable at <http://linux-net.osdl.org/index.php/Iproute2>.
437 If unsure, say Y.
439 config INET_TCP_DIAG
440 depends on INET_DIAG
441 def_tristate INET_DIAG
443 menuconfig TCP_CONG_ADVANCED
444 bool "TCP: advanced congestion control"
445 ---help---
446 Support for selection of various TCP congestion control
447 modules.
449 Nearly all users can safely say no here, and a safe default
450 selection will be made (CUBIC with new Reno as a fallback).
452 If unsure, say N.
454 if TCP_CONG_ADVANCED
456 config TCP_CONG_BIC
457 tristate "Binary Increase Congestion (BIC) control"
458 default m
459 ---help---
460 BIC-TCP is a sender-side only change that ensures a linear RTT
461 fairness under large windows while offering both scalability and
462 bounded TCP-friendliness. The protocol combines two schemes
463 called additive increase and binary search increase. When the
464 congestion window is large, additive increase with a large
465 increment ensures linear RTT fairness as well as good
466 scalability. Under small congestion windows, binary search
467 increase provides TCP friendliness.
468 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/
470 config TCP_CONG_CUBIC
471 tristate "CUBIC TCP"
472 default y
473 ---help---
474 This is version 2.0 of BIC-TCP which uses a cubic growth function
475 among other techniques.
476 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf
478 config TCP_CONG_WESTWOOD
479 tristate "TCP Westwood+"
480 default m
481 ---help---
482 TCP Westwood+ is a sender-side only modification of the TCP Reno
483 protocol stack that optimizes the performance of TCP congestion
484 control. It is based on end-to-end bandwidth estimation to set
485 congestion window and slow start threshold after a congestion
486 episode. Using this estimation, TCP Westwood+ adaptively sets a
487 slow start threshold and a congestion window which takes into
488 account the bandwidth used at the time congestion is experienced.
489 TCP Westwood+ significantly increases fairness wrt TCP Reno in
490 wired networks and throughput over wireless links.
492 config TCP_CONG_HTCP
493 tristate "H-TCP"
494 default m
495 ---help---
496 H-TCP is a send-side only modifications of the TCP Reno
497 protocol stack that optimizes the performance of TCP
498 congestion control for high speed network links. It uses a
499 modeswitch to change the alpha and beta parameters of TCP Reno
500 based on network conditions and in a way so as to be fair with
501 other Reno and H-TCP flows.
503 config TCP_CONG_HSTCP
504 tristate "High Speed TCP"
505 depends on EXPERIMENTAL
506 default n
507 ---help---
508 Sally Floyd's High Speed TCP (RFC 3649) congestion control.
509 A modification to TCP's congestion control mechanism for use
510 with large congestion windows. A table indicates how much to
511 increase the congestion window by when an ACK is received.
512 For more detail see http://www.icir.org/floyd/hstcp.html
514 config TCP_CONG_HYBLA
515 tristate "TCP-Hybla congestion control algorithm"
516 depends on EXPERIMENTAL
517 default n
518 ---help---
519 TCP-Hybla is a sender-side only change that eliminates penalization of
520 long-RTT, large-bandwidth connections, like when satellite legs are
521 involved, especially when sharing a common bottleneck with normal
522 terrestrial connections.
524 config TCP_CONG_VEGAS
525 tristate "TCP Vegas"
526 depends on EXPERIMENTAL
527 default n
528 ---help---
529 TCP Vegas is a sender-side only change to TCP that anticipates
530 the onset of congestion by estimating the bandwidth. TCP Vegas
531 adjusts the sending rate by modifying the congestion
532 window. TCP Vegas should provide less packet loss, but it is
533 not as aggressive as TCP Reno.
535 config TCP_CONG_SCALABLE
536 tristate "Scalable TCP"
537 depends on EXPERIMENTAL
538 default n
539 ---help---
540 Scalable TCP is a sender-side only change to TCP which uses a
541 MIMD congestion control algorithm which has some nice scaling
542 properties, though is known to have fairness issues.
543 See http://www.deneholme.net/tom/scalable/
545 config TCP_CONG_LP
546 tristate "TCP Low Priority"
547 depends on EXPERIMENTAL
548 default n
549 ---help---
550 TCP Low Priority (TCP-LP), a distributed algorithm whose goal is
551 to utilize only the excess network bandwidth as compared to the
552 ``fair share`` of bandwidth as targeted by TCP.
553 See http://www-ece.rice.edu/networks/TCP-LP/
555 config TCP_CONG_VENO
556 tristate "TCP Veno"
557 depends on EXPERIMENTAL
558 default n
559 ---help---
560 TCP Veno is a sender-side only enhancement of TCP to obtain better
561 throughput over wireless networks. TCP Veno makes use of state
562 distinguishing to circumvent the difficult judgment of the packet loss
563 type. TCP Veno cuts down less congestion window in response to random
564 loss packets.
565 See <http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=1177186>
567 config TCP_CONG_YEAH
568 tristate "YeAH TCP"
569 depends on EXPERIMENTAL
570 select TCP_CONG_VEGAS
571 default n
572 ---help---
573 YeAH-TCP is a sender-side high-speed enabled TCP congestion control
574 algorithm, which uses a mixed loss/delay approach to compute the
575 congestion window. It's design goals target high efficiency,
576 internal, RTT and Reno fairness, resilience to link loss while
577 keeping network elements load as low as possible.
579 For further details look here:
580 http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf
582 config TCP_CONG_ILLINOIS
583 tristate "TCP Illinois"
584 depends on EXPERIMENTAL
585 default n
586 ---help---
587 TCP-Illinois is a sender-side modification of TCP Reno for
588 high speed long delay links. It uses round-trip-time to
589 adjust the alpha and beta parameters to achieve a higher average
590 throughput and maintain fairness.
592 For further details see:
593 http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html
595 choice
596 prompt "Default TCP congestion control"
597 default DEFAULT_CUBIC
598 help
599 Select the TCP congestion control that will be used by default
600 for all connections.
602 config DEFAULT_BIC
603 bool "Bic" if TCP_CONG_BIC=y
605 config DEFAULT_CUBIC
606 bool "Cubic" if TCP_CONG_CUBIC=y
608 config DEFAULT_HTCP
609 bool "Htcp" if TCP_CONG_HTCP=y
611 config DEFAULT_HYBLA
612 bool "Hybla" if TCP_CONG_HYBLA=y
614 config DEFAULT_VEGAS
615 bool "Vegas" if TCP_CONG_VEGAS=y
617 config DEFAULT_VENO
618 bool "Veno" if TCP_CONG_VENO=y
620 config DEFAULT_WESTWOOD
621 bool "Westwood" if TCP_CONG_WESTWOOD=y
623 config DEFAULT_RENO
624 bool "Reno"
626 endchoice
628 endif
630 config TCP_CONG_CUBIC
631 tristate
632 depends on !TCP_CONG_ADVANCED
633 default y
635 config DEFAULT_TCP_CONG
636 string
637 default "bic" if DEFAULT_BIC
638 default "cubic" if DEFAULT_CUBIC
639 default "htcp" if DEFAULT_HTCP
640 default "hybla" if DEFAULT_HYBLA
641 default "vegas" if DEFAULT_VEGAS
642 default "westwood" if DEFAULT_WESTWOOD
643 default "veno" if DEFAULT_VENO
644 default "reno" if DEFAULT_RENO
645 default "cubic"
647 config TCP_MD5SIG
648 bool "TCP: MD5 Signature Option support (RFC2385) (EXPERIMENTAL)"
649 depends on EXPERIMENTAL
650 select CRYPTO
651 select CRYPTO_MD5
652 ---help---
653 RFC2385 specifies a method of giving MD5 protection to TCP sessions.
654 Its main (only?) use is to protect BGP sessions between core routers
655 on the Internet.
657 If unsure, say N.