| blob | 0c94a1ac29464247e2dfdd6c4ac14c1dbed3bf79 |
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 and
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.nada.kth.se/~snilsson/public/papers/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
219 tristate "IP: GRE tunnels over IP"
220 help
221 Tunneling means encapsulating data of one protocol type within
222 another protocol and sending it over a channel that understands the
223 encapsulating protocol. This particular tunneling driver implements
224 GRE (Generic Routing Encapsulation) and at this time allows
225 encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure.
226 This driver is useful if the other endpoint is a Cisco router: Cisco
227 likes GRE much better than the other Linux tunneling driver ("IP
228 tunneling" above). In addition, GRE allows multicast redistribution
229 through the tunnel.
231 config NET_IPGRE_BROADCAST
232 bool "IP: broadcast GRE over IP"
233 depends on IP_MULTICAST && NET_IPGRE
234 help
235 One application of GRE/IP is to construct a broadcast WAN (Wide Area
236 Network), which looks like a normal Ethernet LAN (Local Area
237 Network), but can be distributed all over the Internet. If you want
238 to do that, say Y here and to "IP multicast routing" below.
240 config IP_MROUTE
241 bool "IP: multicast routing"
242 depends on IP_MULTICAST
243 help
244 This is used if you want your machine to act as a router for IP
245 packets that have several destination addresses. It is needed on the
246 MBONE, a high bandwidth network on top of the Internet which carries
247 audio and video broadcasts. In order to do that, you would most
248 likely run the program mrouted. Information about the multicast
249 capabilities of the various network cards is contained in
250 <file:Documentation/networking/multicast.txt>. If you haven't heard
251 about it, you don't need it.
253 config IP_PIMSM_V1
254 bool "IP: PIM-SM version 1 support"
255 depends on IP_MROUTE
256 help
257 Kernel side support for Sparse Mode PIM (Protocol Independent
258 Multicast) version 1. This multicast routing protocol is used widely
259 because Cisco supports it. You need special software to use it
260 (pimd-v1). Please see <http://netweb.usc.edu/pim/> for more
261 information about PIM.
263 Say Y if you want to use PIM-SM v1. Note that you can say N here if
264 you just want to use Dense Mode PIM.
266 config IP_PIMSM_V2
267 bool "IP: PIM-SM version 2 support"
268 depends on IP_MROUTE
269 help
270 Kernel side support for Sparse Mode PIM version 2. In order to use
271 this, you need an experimental routing daemon supporting it (pimd or
272 gated-5). This routing protocol is not used widely, so say N unless
273 you want to play with it.
275 config ARPD
276 bool "IP: ARP daemon support"
277 ---help---
278 The kernel maintains an internal cache which maps IP addresses to
279 hardware addresses on the local network, so that Ethernet/Token Ring/
280 etc. frames are sent to the proper address on the physical networking
281 layer. Normally, kernel uses the ARP protocol to resolve these
282 mappings.
284 Saying Y here adds support to have an user space daemon to do this
285 resolution instead. This is useful for implementing an alternate
286 address resolution protocol (e.g. NHRP on mGRE tunnels) and also for
287 testing purposes.
289 If unsure, say N.
291 config SYN_COOKIES
292 bool "IP: TCP syncookie support (disabled per default)"
293 ---help---
294 Normal TCP/IP networking is open to an attack known as "SYN
295 flooding". This denial-of-service attack prevents legitimate remote
296 users from being able to connect to your computer during an ongoing
297 attack and requires very little work from the attacker, who can
298 operate from anywhere on the Internet.
300 SYN cookies provide protection against this type of attack. If you
301 say Y here, the TCP/IP stack will use a cryptographic challenge
302 protocol known as "SYN cookies" to enable legitimate users to
303 continue to connect, even when your machine is under attack. There
304 is no need for the legitimate users to change their TCP/IP software;
305 SYN cookies work transparently to them. For technical information
306 about SYN cookies, check out <http://cr.yp.to/syncookies.html>.
308 If you are SYN flooded, the source address reported by the kernel is
309 likely to have been forged by the attacker; it is only reported as
310 an aid in tracing the packets to their actual source and should not
311 be taken as absolute truth.
313 SYN cookies may prevent correct error reporting on clients when the
314 server is really overloaded. If this happens frequently better turn
315 them off.
317 If you say Y here, note that SYN cookies aren't enabled by default;
318 you can enable them by saying Y to "/proc file system support" and
319 "Sysctl support" below and executing the command
321 echo 1 >/proc/sys/net/ipv4/tcp_syncookies
323 at boot time after the /proc file system has been mounted.
325 If unsure, say N.
327 config INET_AH
328 tristate "IP: AH transformation"
329 select XFRM
330 select CRYPTO
331 select CRYPTO_HMAC
332 select CRYPTO_MD5
333 select CRYPTO_SHA1
334 ---help---
335 Support for IPsec AH.
337 If unsure, say Y.
339 config INET_ESP
340 tristate "IP: ESP transformation"
341 select XFRM
342 select CRYPTO
343 select CRYPTO_AUTHENC
344 select CRYPTO_HMAC
345 select CRYPTO_MD5
346 select CRYPTO_CBC
347 select CRYPTO_SHA1
348 select CRYPTO_DES
349 ---help---
350 Support for IPsec ESP.
352 If unsure, say Y.
354 config INET_IPCOMP
355 tristate "IP: IPComp transformation"
356 select INET_XFRM_TUNNEL
357 select XFRM_IPCOMP
358 ---help---
359 Support for IP Payload Compression Protocol (IPComp) (RFC3173),
360 typically needed for IPsec.
362 If unsure, say Y.
364 config INET_XFRM_TUNNEL
365 tristate
366 select INET_TUNNEL
367 default n
369 config INET_TUNNEL
370 tristate
371 default n
373 config INET_XFRM_MODE_TRANSPORT
374 tristate "IP: IPsec transport mode"
375 default y
376 select XFRM
377 ---help---
378 Support for IPsec transport mode.
380 If unsure, say Y.
382 config INET_XFRM_MODE_TUNNEL
383 tristate "IP: IPsec tunnel mode"
384 default y
385 select XFRM
386 ---help---
387 Support for IPsec tunnel mode.
389 If unsure, say Y.
391 config INET_XFRM_MODE_BEET
392 tristate "IP: IPsec BEET mode"
393 default y
394 select XFRM
395 ---help---
396 Support for IPsec BEET mode.
398 If unsure, say Y.
400 config INET_LRO
401 bool "Large Receive Offload (ipv4/tcp)"
402 default y
403 ---help---
404 Support for Large Receive Offload (ipv4/tcp).
406 If unsure, say Y.
408 config INET_DIAG
409 tristate "INET: socket monitoring interface"
410 default y
411 ---help---
412 Support for INET (TCP, DCCP, etc) socket monitoring interface used by
413 native Linux tools such as ss. ss is included in iproute2, currently
414 downloadable at <http://linux-net.osdl.org/index.php/Iproute2>.
416 If unsure, say Y.
418 config INET_TCP_DIAG
419 depends on INET_DIAG
420 def_tristate INET_DIAG
422 menuconfig TCP_CONG_ADVANCED
423 bool "TCP: advanced congestion control"
424 ---help---
425 Support for selection of various TCP congestion control
426 modules.
428 Nearly all users can safely say no here, and a safe default
429 selection will be made (CUBIC with new Reno as a fallback).
431 If unsure, say N.
433 if TCP_CONG_ADVANCED
435 config TCP_CONG_BIC
436 tristate "Binary Increase Congestion (BIC) control"
437 default m
438 ---help---
439 BIC-TCP is a sender-side only change that ensures a linear RTT
440 fairness under large windows while offering both scalability and
441 bounded TCP-friendliness. The protocol combines two schemes
442 called additive increase and binary search increase. When the
443 congestion window is large, additive increase with a large
444 increment ensures linear RTT fairness as well as good
445 scalability. Under small congestion windows, binary search
446 increase provides TCP friendliness.
447 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/
449 config TCP_CONG_CUBIC
450 tristate "CUBIC TCP"
451 default y
452 ---help---
453 This is version 2.0 of BIC-TCP which uses a cubic growth function
454 among other techniques.
455 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf
457 config TCP_CONG_WESTWOOD
458 tristate "TCP Westwood+"
459 default m
460 ---help---
461 TCP Westwood+ is a sender-side only modification of the TCP Reno
462 protocol stack that optimizes the performance of TCP congestion
463 control. It is based on end-to-end bandwidth estimation to set
464 congestion window and slow start threshold after a congestion
465 episode. Using this estimation, TCP Westwood+ adaptively sets a
466 slow start threshold and a congestion window which takes into
467 account the bandwidth used at the time congestion is experienced.
468 TCP Westwood+ significantly increases fairness wrt TCP Reno in
469 wired networks and throughput over wireless links.
471 config TCP_CONG_HTCP
472 tristate "H-TCP"
473 default m
474 ---help---
475 H-TCP is a send-side only modifications of the TCP Reno
476 protocol stack that optimizes the performance of TCP
477 congestion control for high speed network links. It uses a
478 modeswitch to change the alpha and beta parameters of TCP Reno
479 based on network conditions and in a way so as to be fair with
480 other Reno and H-TCP flows.
482 config TCP_CONG_HSTCP
483 tristate "High Speed TCP"
484 depends on EXPERIMENTAL
485 default n
486 ---help---
487 Sally Floyd's High Speed TCP (RFC 3649) congestion control.
488 A modification to TCP's congestion control mechanism for use
489 with large congestion windows. A table indicates how much to
490 increase the congestion window by when an ACK is received.
491 For more detail see http://www.icir.org/floyd/hstcp.html
493 config TCP_CONG_HYBLA
494 tristate "TCP-Hybla congestion control algorithm"
495 depends on EXPERIMENTAL
496 default n
497 ---help---
498 TCP-Hybla is a sender-side only change that eliminates penalization of
499 long-RTT, large-bandwidth connections, like when satellite legs are
500 involved, especially when sharing a common bottleneck with normal
501 terrestrial connections.
503 config TCP_CONG_VEGAS
504 tristate "TCP Vegas"
505 depends on EXPERIMENTAL
506 default n
507 ---help---
508 TCP Vegas is a sender-side only change to TCP that anticipates
509 the onset of congestion by estimating the bandwidth. TCP Vegas
510 adjusts the sending rate by modifying the congestion
511 window. TCP Vegas should provide less packet loss, but it is
512 not as aggressive as TCP Reno.
514 config TCP_CONG_SCALABLE
515 tristate "Scalable TCP"
516 depends on EXPERIMENTAL
517 default n
518 ---help---
519 Scalable TCP is a sender-side only change to TCP which uses a
520 MIMD congestion control algorithm which has some nice scaling
521 properties, though is known to have fairness issues.
522 See http://www.deneholme.net/tom/scalable/
524 config TCP_CONG_LP
525 tristate "TCP Low Priority"
526 depends on EXPERIMENTAL
527 default n
528 ---help---
529 TCP Low Priority (TCP-LP), a distributed algorithm whose goal is
530 to utilize only the excess network bandwidth as compared to the
531 ``fair share`` of bandwidth as targeted by TCP.
532 See http://www-ece.rice.edu/networks/TCP-LP/
534 config TCP_CONG_VENO
535 tristate "TCP Veno"
536 depends on EXPERIMENTAL
537 default n
538 ---help---
539 TCP Veno is a sender-side only enhancement of TCP to obtain better
540 throughput over wireless networks. TCP Veno makes use of state
541 distinguishing to circumvent the difficult judgment of the packet loss
542 type. TCP Veno cuts down less congestion window in response to random
543 loss packets.
544 See http://www.ntu.edu.sg/home5/ZHOU0022/papers/CPFu03a.pdf
546 config TCP_CONG_YEAH
547 tristate "YeAH TCP"
548 depends on EXPERIMENTAL
549 select TCP_CONG_VEGAS
550 default n
551 ---help---
552 YeAH-TCP is a sender-side high-speed enabled TCP congestion control
553 algorithm, which uses a mixed loss/delay approach to compute the
554 congestion window. It's design goals target high efficiency,
555 internal, RTT and Reno fairness, resilience to link loss while
556 keeping network elements load as low as possible.
558 For further details look here:
559 http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf
561 config TCP_CONG_ILLINOIS
562 tristate "TCP Illinois"
563 depends on EXPERIMENTAL
564 default n
565 ---help---
566 TCP-Illinois is a sender-side modification of TCP Reno for
567 high speed long delay links. It uses round-trip-time to
568 adjust the alpha and beta parameters to achieve a higher average
569 throughput and maintain fairness.
571 For further details see:
572 http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html
574 choice
575 prompt "Default TCP congestion control"
576 default DEFAULT_CUBIC
577 help
578 Select the TCP congestion control that will be used by default
579 for all connections.
581 config DEFAULT_BIC
582 bool "Bic" if TCP_CONG_BIC=y
584 config DEFAULT_CUBIC
585 bool "Cubic" if TCP_CONG_CUBIC=y
587 config DEFAULT_HTCP
588 bool "Htcp" if TCP_CONG_HTCP=y
590 config DEFAULT_VEGAS
591 bool "Vegas" if TCP_CONG_VEGAS=y
593 config DEFAULT_WESTWOOD
594 bool "Westwood" if TCP_CONG_WESTWOOD=y
596 config DEFAULT_RENO
597 bool "Reno"
599 endchoice
601 endif
603 config TCP_CONG_CUBIC
604 tristate
605 depends on !TCP_CONG_ADVANCED
606 default y
608 config DEFAULT_TCP_CONG
609 string
610 default "bic" if DEFAULT_BIC
611 default "cubic" if DEFAULT_CUBIC
612 default "htcp" if DEFAULT_HTCP
613 default "vegas" if DEFAULT_VEGAS
614 default "westwood" if DEFAULT_WESTWOOD
615 default "reno" if DEFAULT_RENO
616 default "cubic"
618 config TCP_MD5SIG
619 bool "TCP: MD5 Signature Option support (RFC2385) (EXPERIMENTAL)"
620 depends on EXPERIMENTAL
621 select CRYPTO
622 select CRYPTO_MD5
623 ---help---
624 RFC2385 specifies a method of giving MD5 protection to TCP sessions.
625 Its main (only?) use is to protect BGP sessions between core routers
626 on the Internet.
628 If unsure, say N.