| blob | 40996e29bcfa54b6fbd7817ba2321a3003806ced |
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 config IP_FIB_TRIE_STATS
59 bool "FIB TRIE statistics"
60 depends on IP_ADVANCED_ROUTER
61 ---help---
62 Keep track of statistics on structure of FIB TRIE table.
63 Useful for testing and measuring TRIE performance.
65 config IP_MULTIPLE_TABLES
66 bool "IP: policy routing"
67 depends on IP_ADVANCED_ROUTER
68 select FIB_RULES
69 ---help---
70 Normally, a router decides what to do with a received packet based
71 solely on the packet's final destination address. If you say Y here,
72 the Linux router will also be able to take the packet's source
73 address into account. Furthermore, the TOS (Type-Of-Service) field
74 of the packet can be used for routing decisions as well.
76 If you are interested in this, please see the preliminary
77 documentation at <http://www.compendium.com.ar/policy-routing.txt>
78 and <ftp://post.tepkom.ru/pub/vol2/Linux/docs/advanced-routing.tex>.
79 You will need supporting software from
80 <ftp://ftp.tux.org/pub/net/ip-routing/>.
82 If unsure, say N.
84 config IP_ROUTE_MULTIPATH
85 bool "IP: equal cost multipath"
86 depends on IP_ADVANCED_ROUTER
87 help
88 Normally, the routing tables specify a single action to be taken in
89 a deterministic manner for a given packet. If you say Y here
90 however, it becomes possible to attach several actions to a packet
91 pattern, in effect specifying several alternative paths to travel
92 for those packets. The router considers all these paths to be of
93 equal "cost" and chooses one of them in a non-deterministic fashion
94 if a matching packet arrives.
96 config IP_ROUTE_VERBOSE
97 bool "IP: verbose route monitoring"
98 depends on IP_ADVANCED_ROUTER
99 help
100 If you say Y here, which is recommended, then the kernel will print
101 verbose messages regarding the routing, for example warnings about
102 received packets which look strange and could be evidence of an
103 attack or a misconfigured system somewhere. The information is
104 handled by the klogd daemon which is responsible for kernel messages
105 ("man klogd").
107 config IP_ROUTE_CLASSID
108 bool
110 config IP_PNP
111 bool "IP: kernel level autoconfiguration"
112 help
113 This enables automatic configuration of IP addresses of devices and
114 of the routing table during kernel boot, based on either information
115 supplied on the kernel command line or by BOOTP or RARP protocols.
116 You need to say Y only for diskless machines requiring network
117 access to boot (in which case you want to say Y to "Root file system
118 on NFS" as well), because all other machines configure the network
119 in their startup scripts.
121 config IP_PNP_DHCP
122 bool "IP: DHCP support"
123 depends on IP_PNP
124 ---help---
125 If you want your Linux box to mount its whole root file system (the
126 one containing the directory /) from some other computer over the
127 net via NFS and you want the IP address of your computer to be
128 discovered automatically at boot time using the DHCP protocol (a
129 special protocol designed for doing this job), say Y here. In case
130 the boot ROM of your network card was designed for booting Linux and
131 does DHCP itself, providing all necessary information on the kernel
132 command line, you can say N here.
134 If unsure, say Y. Note that if you want to use DHCP, a DHCP server
135 must be operating on your network. Read
136 <file:Documentation/filesystems/nfs/nfsroot.txt> for details.
138 config IP_PNP_BOOTP
139 bool "IP: BOOTP support"
140 depends on IP_PNP
141 ---help---
142 If you want your Linux box to mount its whole root file system (the
143 one containing the directory /) from some other computer over the
144 net via NFS and you want the IP address of your computer to be
145 discovered automatically at boot time using the BOOTP protocol (a
146 special protocol designed for doing this job), say Y here. In case
147 the boot ROM of your network card was designed for booting Linux and
148 does BOOTP itself, providing all necessary information on the kernel
149 command line, you can say N here. If unsure, say Y. Note that if you
150 want to use BOOTP, a BOOTP server must be operating on your network.
151 Read <file:Documentation/filesystems/nfs/nfsroot.txt> for details.
153 config IP_PNP_RARP
154 bool "IP: RARP support"
155 depends on IP_PNP
156 help
157 If you want your Linux box to mount its whole root file system (the
158 one containing the directory /) from some other computer over the
159 net via NFS and you want the IP address of your computer to be
160 discovered automatically at boot time using the RARP protocol (an
161 older protocol which is being obsoleted by BOOTP and DHCP), say Y
162 here. Note that if you want to use RARP, a RARP server must be
163 operating on your network. Read
164 <file:Documentation/filesystems/nfs/nfsroot.txt> for details.
166 config NET_IPIP
167 tristate "IP: tunneling"
168 select INET_TUNNEL
169 ---help---
170 Tunneling means encapsulating data of one protocol type within
171 another protocol and sending it over a channel that understands the
172 encapsulating protocol. This particular tunneling driver implements
173 encapsulation of IP within IP, which sounds kind of pointless, but
174 can be useful if you want to make your (or some other) machine
175 appear on a different network than it physically is, or to use
176 mobile-IP facilities (allowing laptops to seamlessly move between
177 networks without changing their IP addresses).
179 Saying Y to this option will produce two modules ( = code which can
180 be inserted in and removed from the running kernel whenever you
181 want). Most people won't need this and can say N.
183 config NET_IPGRE_DEMUX
184 tristate "IP: GRE demultiplexer"
185 help
186 This is helper module to demultiplex GRE packets on GRE version field criteria.
187 Required by ip_gre and pptp modules.
189 config NET_IPGRE
190 tristate "IP: GRE tunnels over IP"
191 depends on (IPV6 || IPV6=n) && NET_IPGRE_DEMUX
192 help
193 Tunneling means encapsulating data of one protocol type within
194 another protocol and sending it over a channel that understands the
195 encapsulating protocol. This particular tunneling driver implements
196 GRE (Generic Routing Encapsulation) and at this time allows
197 encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure.
198 This driver is useful if the other endpoint is a Cisco router: Cisco
199 likes GRE much better than the other Linux tunneling driver ("IP
200 tunneling" above). In addition, GRE allows multicast redistribution
201 through the tunnel.
203 config NET_IPGRE_BROADCAST
204 bool "IP: broadcast GRE over IP"
205 depends on IP_MULTICAST && NET_IPGRE
206 help
207 One application of GRE/IP is to construct a broadcast WAN (Wide Area
208 Network), which looks like a normal Ethernet LAN (Local Area
209 Network), but can be distributed all over the Internet. If you want
210 to do that, say Y here and to "IP multicast routing" below.
212 config IP_MROUTE
213 bool "IP: multicast routing"
214 depends on IP_MULTICAST
215 help
216 This is used if you want your machine to act as a router for IP
217 packets that have several destination addresses. It is needed on the
218 MBONE, a high bandwidth network on top of the Internet which carries
219 audio and video broadcasts. In order to do that, you would most
220 likely run the program mrouted. Information about the multicast
221 capabilities of the various network cards is contained in
222 <file:Documentation/networking/multicast.txt>. If you haven't heard
223 about it, you don't need it.
225 config IP_MROUTE_MULTIPLE_TABLES
226 bool "IP: multicast policy routing"
227 depends on IP_MROUTE && IP_ADVANCED_ROUTER
228 select FIB_RULES
229 help
230 Normally, a multicast router runs a userspace daemon and decides
231 what to do with a multicast packet based on the source and
232 destination addresses. If you say Y here, the multicast router
233 will also be able to take interfaces and packet marks into
234 account and run multiple instances of userspace daemons
235 simultaneously, each one handling a single table.
237 If unsure, say N.
239 config IP_PIMSM_V1
240 bool "IP: PIM-SM version 1 support"
241 depends on IP_MROUTE
242 help
243 Kernel side support for Sparse Mode PIM (Protocol Independent
244 Multicast) version 1. This multicast routing protocol is used widely
245 because Cisco supports it. You need special software to use it
246 (pimd-v1). Please see <http://netweb.usc.edu/pim/> for more
247 information about PIM.
249 Say Y if you want to use PIM-SM v1. Note that you can say N here if
250 you just want to use Dense Mode PIM.
252 config IP_PIMSM_V2
253 bool "IP: PIM-SM version 2 support"
254 depends on IP_MROUTE
255 help
256 Kernel side support for Sparse Mode PIM version 2. In order to use
257 this, you need an experimental routing daemon supporting it (pimd or
258 gated-5). This routing protocol is not used widely, so say N unless
259 you want to play with it.
261 config ARPD
262 bool "IP: ARP daemon support"
263 ---help---
264 The kernel maintains an internal cache which maps IP addresses to
265 hardware addresses on the local network, so that Ethernet/Token Ring/
266 etc. frames are sent to the proper address on the physical networking
267 layer. Normally, kernel uses the ARP protocol to resolve these
268 mappings.
270 Saying Y here adds support to have an user space daemon to do this
271 resolution instead. This is useful for implementing an alternate
272 address resolution protocol (e.g. NHRP on mGRE tunnels) and also for
273 testing purposes.
275 If unsure, say N.
277 config SYN_COOKIES
278 bool "IP: TCP syncookie support"
279 ---help---
280 Normal TCP/IP networking is open to an attack known as "SYN
281 flooding". This denial-of-service attack prevents legitimate remote
282 users from being able to connect to your computer during an ongoing
283 attack and requires very little work from the attacker, who can
284 operate from anywhere on the Internet.
286 SYN cookies provide protection against this type of attack. If you
287 say Y here, the TCP/IP stack will use a cryptographic challenge
288 protocol known as "SYN cookies" to enable legitimate users to
289 continue to connect, even when your machine is under attack. There
290 is no need for the legitimate users to change their TCP/IP software;
291 SYN cookies work transparently to them. For technical information
292 about SYN cookies, check out <http://cr.yp.to/syncookies.html>.
294 If you are SYN flooded, the source address reported by the kernel is
295 likely to have been forged by the attacker; it is only reported as
296 an aid in tracing the packets to their actual source and should not
297 be taken as absolute truth.
299 SYN cookies may prevent correct error reporting on clients when the
300 server is really overloaded. If this happens frequently better turn
301 them off.
303 If you say Y here, you can disable SYN cookies at run time by
304 saying Y to "/proc file system support" and
305 "Sysctl support" below and executing the command
307 echo 0 > /proc/sys/net/ipv4/tcp_syncookies
309 after the /proc file system has been mounted.
311 If unsure, say N.
313 config INET_AH
314 tristate "IP: AH transformation"
315 select XFRM
316 select CRYPTO
317 select CRYPTO_HMAC
318 select CRYPTO_MD5
319 select CRYPTO_SHA1
320 ---help---
321 Support for IPsec AH.
323 If unsure, say Y.
325 config INET_ESP
326 tristate "IP: ESP transformation"
327 select XFRM
328 select CRYPTO
329 select CRYPTO_AUTHENC
330 select CRYPTO_HMAC
331 select CRYPTO_MD5
332 select CRYPTO_CBC
333 select CRYPTO_SHA1
334 select CRYPTO_DES
335 ---help---
336 Support for IPsec ESP.
338 If unsure, say Y.
340 config INET_IPCOMP
341 tristate "IP: IPComp transformation"
342 select INET_XFRM_TUNNEL
343 select XFRM_IPCOMP
344 ---help---
345 Support for IP Payload Compression Protocol (IPComp) (RFC3173),
346 typically needed for IPsec.
348 If unsure, say Y.
350 config INET_XFRM_TUNNEL
351 tristate
352 select INET_TUNNEL
353 default n
355 config INET_TUNNEL
356 tristate
357 default n
359 config INET_XFRM_MODE_TRANSPORT
360 tristate "IP: IPsec transport mode"
361 default y
362 select XFRM
363 ---help---
364 Support for IPsec transport mode.
366 If unsure, say Y.
368 config INET_XFRM_MODE_TUNNEL
369 tristate "IP: IPsec tunnel mode"
370 default y
371 select XFRM
372 ---help---
373 Support for IPsec tunnel mode.
375 If unsure, say Y.
377 config INET_XFRM_MODE_BEET
378 tristate "IP: IPsec BEET mode"
379 default y
380 select XFRM
381 ---help---
382 Support for IPsec BEET mode.
384 If unsure, say Y.
386 config INET_LRO
387 tristate "Large Receive Offload (ipv4/tcp)"
388 default y
389 ---help---
390 Support for Large Receive Offload (ipv4/tcp).
392 If unsure, say Y.
394 config INET_DIAG
395 tristate "INET: socket monitoring interface"
396 default y
397 ---help---
398 Support for INET (TCP, DCCP, etc) socket monitoring interface used by
399 native Linux tools such as ss. ss is included in iproute2, currently
400 downloadable at:
402 http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2
404 If unsure, say Y.
406 config INET_TCP_DIAG
407 depends on INET_DIAG
408 def_tristate INET_DIAG
410 config INET_UDP_DIAG
411 tristate "UDP: socket monitoring interface"
412 depends on INET_DIAG && (IPV6 || IPV6=n)
413 default n
414 ---help---
415 Support for UDP socket monitoring interface used by the ss tool.
416 If unsure, say Y.
418 menuconfig TCP_CONG_ADVANCED
419 bool "TCP: advanced congestion control"
420 ---help---
421 Support for selection of various TCP congestion control
422 modules.
424 Nearly all users can safely say no here, and a safe default
425 selection will be made (CUBIC with new Reno as a fallback).
427 If unsure, say N.
429 if TCP_CONG_ADVANCED
431 config TCP_CONG_BIC
432 tristate "Binary Increase Congestion (BIC) control"
433 default m
434 ---help---
435 BIC-TCP is a sender-side only change that ensures a linear RTT
436 fairness under large windows while offering both scalability and
437 bounded TCP-friendliness. The protocol combines two schemes
438 called additive increase and binary search increase. When the
439 congestion window is large, additive increase with a large
440 increment ensures linear RTT fairness as well as good
441 scalability. Under small congestion windows, binary search
442 increase provides TCP friendliness.
443 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/
445 config TCP_CONG_CUBIC
446 tristate "CUBIC TCP"
447 default y
448 ---help---
449 This is version 2.0 of BIC-TCP which uses a cubic growth function
450 among other techniques.
451 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf
453 config TCP_CONG_WESTWOOD
454 tristate "TCP Westwood+"
455 default m
456 ---help---
457 TCP Westwood+ is a sender-side only modification of the TCP Reno
458 protocol stack that optimizes the performance of TCP congestion
459 control. It is based on end-to-end bandwidth estimation to set
460 congestion window and slow start threshold after a congestion
461 episode. Using this estimation, TCP Westwood+ adaptively sets a
462 slow start threshold and a congestion window which takes into
463 account the bandwidth used at the time congestion is experienced.
464 TCP Westwood+ significantly increases fairness wrt TCP Reno in
465 wired networks and throughput over wireless links.
467 config TCP_CONG_HTCP
468 tristate "H-TCP"
469 default m
470 ---help---
471 H-TCP is a send-side only modifications of the TCP Reno
472 protocol stack that optimizes the performance of TCP
473 congestion control for high speed network links. It uses a
474 modeswitch to change the alpha and beta parameters of TCP Reno
475 based on network conditions and in a way so as to be fair with
476 other Reno and H-TCP flows.
478 config TCP_CONG_HSTCP
479 tristate "High Speed TCP"
480 depends on EXPERIMENTAL
481 default n
482 ---help---
483 Sally Floyd's High Speed TCP (RFC 3649) congestion control.
484 A modification to TCP's congestion control mechanism for use
485 with large congestion windows. A table indicates how much to
486 increase the congestion window by when an ACK is received.
487 For more detail see http://www.icir.org/floyd/hstcp.html
489 config TCP_CONG_HYBLA
490 tristate "TCP-Hybla congestion control algorithm"
491 depends on EXPERIMENTAL
492 default n
493 ---help---
494 TCP-Hybla is a sender-side only change that eliminates penalization of
495 long-RTT, large-bandwidth connections, like when satellite legs are
496 involved, especially when sharing a common bottleneck with normal
497 terrestrial connections.
499 config TCP_CONG_VEGAS
500 tristate "TCP Vegas"
501 depends on EXPERIMENTAL
502 default n
503 ---help---
504 TCP Vegas is a sender-side only change to TCP that anticipates
505 the onset of congestion by estimating the bandwidth. TCP Vegas
506 adjusts the sending rate by modifying the congestion
507 window. TCP Vegas should provide less packet loss, but it is
508 not as aggressive as TCP Reno.
510 config TCP_CONG_SCALABLE
511 tristate "Scalable TCP"
512 depends on EXPERIMENTAL
513 default n
514 ---help---
515 Scalable TCP is a sender-side only change to TCP which uses a
516 MIMD congestion control algorithm which has some nice scaling
517 properties, though is known to have fairness issues.
518 See http://www.deneholme.net/tom/scalable/
520 config TCP_CONG_LP
521 tristate "TCP Low Priority"
522 depends on EXPERIMENTAL
523 default n
524 ---help---
525 TCP Low Priority (TCP-LP), a distributed algorithm whose goal is
526 to utilize only the excess network bandwidth as compared to the
527 ``fair share`` of bandwidth as targeted by TCP.
528 See http://www-ece.rice.edu/networks/TCP-LP/
530 config TCP_CONG_VENO
531 tristate "TCP Veno"
532 depends on EXPERIMENTAL
533 default n
534 ---help---
535 TCP Veno is a sender-side only enhancement of TCP to obtain better
536 throughput over wireless networks. TCP Veno makes use of state
537 distinguishing to circumvent the difficult judgment of the packet loss
538 type. TCP Veno cuts down less congestion window in response to random
539 loss packets.
540 See <http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=1177186>
542 config TCP_CONG_YEAH
543 tristate "YeAH TCP"
544 depends on EXPERIMENTAL
545 select TCP_CONG_VEGAS
546 default n
547 ---help---
548 YeAH-TCP is a sender-side high-speed enabled TCP congestion control
549 algorithm, which uses a mixed loss/delay approach to compute the
550 congestion window. It's design goals target high efficiency,
551 internal, RTT and Reno fairness, resilience to link loss while
552 keeping network elements load as low as possible.
554 For further details look here:
555 http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf
557 config TCP_CONG_ILLINOIS
558 tristate "TCP Illinois"
559 depends on EXPERIMENTAL
560 default n
561 ---help---
562 TCP-Illinois is a sender-side modification of TCP Reno for
563 high speed long delay links. It uses round-trip-time to
564 adjust the alpha and beta parameters to achieve a higher average
565 throughput and maintain fairness.
567 For further details see:
568 http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html
570 choice
571 prompt "Default TCP congestion control"
572 default DEFAULT_CUBIC
573 help
574 Select the TCP congestion control that will be used by default
575 for all connections.
577 config DEFAULT_BIC
578 bool "Bic" if TCP_CONG_BIC=y
580 config DEFAULT_CUBIC
581 bool "Cubic" if TCP_CONG_CUBIC=y
583 config DEFAULT_HTCP
584 bool "Htcp" if TCP_CONG_HTCP=y
586 config DEFAULT_HYBLA
587 bool "Hybla" if TCP_CONG_HYBLA=y
589 config DEFAULT_VEGAS
590 bool "Vegas" if TCP_CONG_VEGAS=y
592 config DEFAULT_YEAH
593 bool "YeAH" if TCP_CONG_YEAH=y
595 config DEFAULT_VENO
596 bool "Veno" if TCP_CONG_VENO=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 "hybla" if DEFAULT_HYBLA
619 default "vegas" if DEFAULT_VEGAS
620 default "yeah" if DEFAULT_YEAH
621 default "westwood" if DEFAULT_WESTWOOD
622 default "veno" if DEFAULT_VENO
623 default "reno" if DEFAULT_RENO
624 default "cubic"
626 config TCP_MD5SIG
627 bool "TCP: MD5 Signature Option support (RFC2385) (EXPERIMENTAL)"
628 depends on EXPERIMENTAL
629 select CRYPTO
630 select CRYPTO_MD5
631 ---help---
632 RFC2385 specifies a method of giving MD5 protection to TCP sessions.
633 Its main (only?) use is to protect BGP sessions between core routers
634 on the Internet.
636 If unsure, say N.