xref: /openbmc/linux/net/ipv4/Kconfig (revision b2765275)
1# SPDX-License-Identifier: GPL-2.0-only
2#
3# IP configuration
4#
5config IP_MULTICAST
6	bool "IP: multicasting"
7	help
8	  This is code for addressing several networked computers at once,
9	  enlarging your kernel by about 2 KB. You need multicasting if you
10	  intend to participate in the MBONE, a high bandwidth network on top
11	  of the Internet which carries audio and video broadcasts. More
12	  information about the MBONE is on the WWW at
13	  <http://www.savetz.com/mbone/>. For most people, it's safe to say N.
14
15config IP_ADVANCED_ROUTER
16	bool "IP: advanced router"
17	---help---
18	  If you intend to run your Linux box mostly as a router, i.e. as a
19	  computer that forwards and redistributes network packets, say Y; you
20	  will then be presented with several options that allow more precise
21	  control about the routing process.
22
23	  The answer to this question won't directly affect the kernel:
24	  answering N will just cause the configurator to skip all the
25	  questions about advanced routing.
26
27	  Note that your box can only act as a router if you enable IP
28	  forwarding in your kernel; you can do that by saying Y to "/proc
29	  file system support" and "Sysctl support" below and executing the
30	  line
31
32	  echo "1" > /proc/sys/net/ipv4/ip_forward
33
34	  at boot time after the /proc file system has been mounted.
35
36	  If you turn on IP forwarding, you should consider the rp_filter, which
37	  automatically rejects incoming packets if the routing table entry
38	  for their source address doesn't match the network interface they're
39	  arriving on. This has security advantages because it prevents the
40	  so-called IP spoofing, however it can pose problems if you use
41	  asymmetric routing (packets from you to a host take a different path
42	  than packets from that host to you) or if you operate a non-routing
43	  host which has several IP addresses on different interfaces. To turn
44	  rp_filter on use:
45
46	  echo 1 > /proc/sys/net/ipv4/conf/<device>/rp_filter
47	   or
48	  echo 1 > /proc/sys/net/ipv4/conf/all/rp_filter
49
50	  Note that some distributions enable it in startup scripts.
51	  For details about rp_filter strict and loose mode read
52	  <file:Documentation/networking/ip-sysctl.txt>.
53
54	  If unsure, say N here.
55
56config IP_FIB_TRIE_STATS
57	bool "FIB TRIE statistics"
58	depends on IP_ADVANCED_ROUTER
59	---help---
60	  Keep track of statistics on structure of FIB TRIE table.
61	  Useful for testing and measuring TRIE performance.
62
63config IP_MULTIPLE_TABLES
64	bool "IP: policy routing"
65	depends on IP_ADVANCED_ROUTER
66	select FIB_RULES
67	---help---
68	  Normally, a router decides what to do with a received packet based
69	  solely on the packet's final destination address. If you say Y here,
70	  the Linux router will also be able to take the packet's source
71	  address into account. Furthermore, the TOS (Type-Of-Service) field
72	  of the packet can be used for routing decisions as well.
73
74	  If you need more information, see the Linux Advanced
75	  Routing and Traffic Control documentation at
76	  <http://lartc.org/howto/lartc.rpdb.html>
77
78	  If unsure, say N.
79
80config IP_ROUTE_MULTIPATH
81	bool "IP: equal cost multipath"
82	depends on IP_ADVANCED_ROUTER
83	help
84	  Normally, the routing tables specify a single action to be taken in
85	  a deterministic manner for a given packet. If you say Y here
86	  however, it becomes possible to attach several actions to a packet
87	  pattern, in effect specifying several alternative paths to travel
88	  for those packets. The router considers all these paths to be of
89	  equal "cost" and chooses one of them in a non-deterministic fashion
90	  if a matching packet arrives.
91
92config IP_ROUTE_VERBOSE
93	bool "IP: verbose route monitoring"
94	depends on IP_ADVANCED_ROUTER
95	help
96	  If you say Y here, which is recommended, then the kernel will print
97	  verbose messages regarding the routing, for example warnings about
98	  received packets which look strange and could be evidence of an
99	  attack or a misconfigured system somewhere. The information is
100	  handled by the klogd daemon which is responsible for kernel messages
101	  ("man klogd").
102
103config IP_ROUTE_CLASSID
104	bool
105
106config IP_PNP
107	bool "IP: kernel level autoconfiguration"
108	help
109	  This enables automatic configuration of IP addresses of devices and
110	  of the routing table during kernel boot, based on either information
111	  supplied on the kernel command line or by BOOTP or RARP protocols.
112	  You need to say Y only for diskless machines requiring network
113	  access to boot (in which case you want to say Y to "Root file system
114	  on NFS" as well), because all other machines configure the network
115	  in their startup scripts.
116
117config IP_PNP_DHCP
118	bool "IP: DHCP support"
119	depends on IP_PNP
120	---help---
121	  If you want your Linux box to mount its whole root file system (the
122	  one containing the directory /) from some other computer over the
123	  net via NFS and you want the IP address of your computer to be
124	  discovered automatically at boot time using the DHCP protocol (a
125	  special protocol designed for doing this job), say Y here. In case
126	  the boot ROM of your network card was designed for booting Linux and
127	  does DHCP itself, providing all necessary information on the kernel
128	  command line, you can say N here.
129
130	  If unsure, say Y. Note that if you want to use DHCP, a DHCP server
131	  must be operating on your network.  Read
132	  <file:Documentation/filesystems/nfs/nfsroot.txt> for details.
133
134config IP_PNP_BOOTP
135	bool "IP: BOOTP support"
136	depends on IP_PNP
137	---help---
138	  If you want your Linux box to mount its whole root file system (the
139	  one containing the directory /) from some other computer over the
140	  net via NFS and you want the IP address of your computer to be
141	  discovered automatically at boot time using the BOOTP protocol (a
142	  special protocol designed for doing this job), say Y here. In case
143	  the boot ROM of your network card was designed for booting Linux and
144	  does BOOTP itself, providing all necessary information on the kernel
145	  command line, you can say N here. If unsure, say Y. Note that if you
146	  want to use BOOTP, a BOOTP server must be operating on your network.
147	  Read <file:Documentation/filesystems/nfs/nfsroot.txt> for details.
148
149config IP_PNP_RARP
150	bool "IP: RARP support"
151	depends on IP_PNP
152	help
153	  If you want your Linux box to mount its whole root file system (the
154	  one containing the directory /) from some other computer over the
155	  net via NFS and you want the IP address of your computer to be
156	  discovered automatically at boot time using the RARP protocol (an
157	  older protocol which is being obsoleted by BOOTP and DHCP), say Y
158	  here. Note that if you want to use RARP, a RARP server must be
159	  operating on your network. Read
160	  <file:Documentation/filesystems/nfs/nfsroot.txt> for details.
161
162config NET_IPIP
163	tristate "IP: tunneling"
164	select INET_TUNNEL
165	select NET_IP_TUNNEL
166	---help---
167	  Tunneling means encapsulating data of one protocol type within
168	  another protocol and sending it over a channel that understands the
169	  encapsulating protocol. This particular tunneling driver implements
170	  encapsulation of IP within IP, which sounds kind of pointless, but
171	  can be useful if you want to make your (or some other) machine
172	  appear on a different network than it physically is, or to use
173	  mobile-IP facilities (allowing laptops to seamlessly move between
174	  networks without changing their IP addresses).
175
176	  Saying Y to this option will produce two modules ( = code which can
177	  be inserted in and removed from the running kernel whenever you
178	  want). Most people won't need this and can say N.
179
180config NET_IPGRE_DEMUX
181	tristate "IP: GRE demultiplexer"
182	help
183	  This is helper module to demultiplex GRE packets on GRE version field criteria.
184	  Required by ip_gre and pptp modules.
185
186config NET_IP_TUNNEL
187	tristate
188	select DST_CACHE
189	select GRO_CELLS
190	default n
191
192config NET_IPGRE
193	tristate "IP: GRE tunnels over IP"
194	depends on (IPV6 || IPV6=n) && NET_IPGRE_DEMUX
195	select NET_IP_TUNNEL
196	help
197	  Tunneling means encapsulating data of one protocol type within
198	  another protocol and sending it over a channel that understands the
199	  encapsulating protocol. This particular tunneling driver implements
200	  GRE (Generic Routing Encapsulation) and at this time allows
201	  encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure.
202	  This driver is useful if the other endpoint is a Cisco router: Cisco
203	  likes GRE much better than the other Linux tunneling driver ("IP
204	  tunneling" above). In addition, GRE allows multicast redistribution
205	  through the tunnel.
206
207config NET_IPGRE_BROADCAST
208	bool "IP: broadcast GRE over IP"
209	depends on IP_MULTICAST && NET_IPGRE
210	help
211	  One application of GRE/IP is to construct a broadcast WAN (Wide Area
212	  Network), which looks like a normal Ethernet LAN (Local Area
213	  Network), but can be distributed all over the Internet. If you want
214	  to do that, say Y here and to "IP multicast routing" below.
215
216config IP_MROUTE_COMMON
217	bool
218	depends on IP_MROUTE || IPV6_MROUTE
219
220config IP_MROUTE
221	bool "IP: multicast routing"
222	depends on IP_MULTICAST
223	select IP_MROUTE_COMMON
224	help
225	  This is used if you want your machine to act as a router for IP
226	  packets that have several destination addresses. It is needed on the
227	  MBONE, a high bandwidth network on top of the Internet which carries
228	  audio and video broadcasts. In order to do that, you would most
229	  likely run the program mrouted. If you haven't heard about it, you
230	  don't need it.
231
232config IP_MROUTE_MULTIPLE_TABLES
233	bool "IP: multicast policy routing"
234	depends on IP_MROUTE && IP_ADVANCED_ROUTER
235	select FIB_RULES
236	help
237	  Normally, a multicast router runs a userspace daemon and decides
238	  what to do with a multicast packet based on the source and
239	  destination addresses. If you say Y here, the multicast router
240	  will also be able to take interfaces and packet marks into
241	  account and run multiple instances of userspace daemons
242	  simultaneously, each one handling a single table.
243
244	  If unsure, say N.
245
246config IP_PIMSM_V1
247	bool "IP: PIM-SM version 1 support"
248	depends on IP_MROUTE
249	help
250	  Kernel side support for Sparse Mode PIM (Protocol Independent
251	  Multicast) version 1. This multicast routing protocol is used widely
252	  because Cisco supports it. You need special software to use it
253	  (pimd-v1). Please see <http://netweb.usc.edu/pim/> for more
254	  information about PIM.
255
256	  Say Y if you want to use PIM-SM v1. Note that you can say N here if
257	  you just want to use Dense Mode PIM.
258
259config IP_PIMSM_V2
260	bool "IP: PIM-SM version 2 support"
261	depends on IP_MROUTE
262	help
263	  Kernel side support for Sparse Mode PIM version 2. In order to use
264	  this, you need an experimental routing daemon supporting it (pimd or
265	  gated-5). This routing protocol is not used widely, so say N unless
266	  you want to play with it.
267
268config SYN_COOKIES
269	bool "IP: TCP syncookie support"
270	---help---
271	  Normal TCP/IP networking is open to an attack known as "SYN
272	  flooding". This denial-of-service attack prevents legitimate remote
273	  users from being able to connect to your computer during an ongoing
274	  attack and requires very little work from the attacker, who can
275	  operate from anywhere on the Internet.
276
277	  SYN cookies provide protection against this type of attack. If you
278	  say Y here, the TCP/IP stack will use a cryptographic challenge
279	  protocol known as "SYN cookies" to enable legitimate users to
280	  continue to connect, even when your machine is under attack. There
281	  is no need for the legitimate users to change their TCP/IP software;
282	  SYN cookies work transparently to them. For technical information
283	  about SYN cookies, check out <http://cr.yp.to/syncookies.html>.
284
285	  If you are SYN flooded, the source address reported by the kernel is
286	  likely to have been forged by the attacker; it is only reported as
287	  an aid in tracing the packets to their actual source and should not
288	  be taken as absolute truth.
289
290	  SYN cookies may prevent correct error reporting on clients when the
291	  server is really overloaded. If this happens frequently better turn
292	  them off.
293
294	  If you say Y here, you can disable SYN cookies at run time by
295	  saying Y to "/proc file system support" and
296	  "Sysctl support" below and executing the command
297
298	  echo 0 > /proc/sys/net/ipv4/tcp_syncookies
299
300	  after the /proc file system has been mounted.
301
302	  If unsure, say N.
303
304config NET_IPVTI
305	tristate "Virtual (secure) IP: tunneling"
306	select INET_TUNNEL
307	select NET_IP_TUNNEL
308	select XFRM
309	---help---
310	  Tunneling means encapsulating data of one protocol type within
311	  another protocol and sending it over a channel that understands the
312	  encapsulating protocol. This can be used with xfrm mode tunnel to give
313	  the notion of a secure tunnel for IPSEC and then use routing protocol
314	  on top.
315
316config NET_UDP_TUNNEL
317	tristate
318	select NET_IP_TUNNEL
319	default n
320
321config NET_FOU
322	tristate "IP: Foo (IP protocols) over UDP"
323	select XFRM
324	select NET_UDP_TUNNEL
325	---help---
326	  Foo over UDP allows any IP protocol to be directly encapsulated
327	  over UDP include tunnels (IPIP, GRE, SIT). By encapsulating in UDP
328	  network mechanisms and optimizations for UDP (such as ECMP
329	  and RSS) can be leveraged to provide better service.
330
331config NET_FOU_IP_TUNNELS
332	bool "IP: FOU encapsulation of IP tunnels"
333	depends on NET_IPIP || NET_IPGRE || IPV6_SIT
334	select NET_FOU
335	---help---
336	  Allow configuration of FOU or GUE encapsulation for IP tunnels.
337	  When this option is enabled IP tunnels can be configured to use
338	  FOU or GUE encapsulation.
339
340config INET_AH
341	tristate "IP: AH transformation"
342	select XFRM_ALGO
343	select CRYPTO
344	select CRYPTO_HMAC
345	select CRYPTO_MD5
346	select CRYPTO_SHA1
347	---help---
348	  Support for IPsec AH.
349
350	  If unsure, say Y.
351
352config INET_ESP
353	tristate "IP: ESP transformation"
354	select XFRM_ALGO
355	select CRYPTO
356	select CRYPTO_AUTHENC
357	select CRYPTO_HMAC
358	select CRYPTO_MD5
359	select CRYPTO_CBC
360	select CRYPTO_SHA1
361	select CRYPTO_DES
362	select CRYPTO_ECHAINIV
363	---help---
364	  Support for IPsec ESP.
365
366	  If unsure, say Y.
367
368config INET_ESP_OFFLOAD
369	tristate "IP: ESP transformation offload"
370	depends on INET_ESP
371	select XFRM_OFFLOAD
372	default n
373	---help---
374	  Support for ESP transformation offload. This makes sense
375	  only if this system really does IPsec and want to do it
376	  with high throughput. A typical desktop system does not
377	  need it, even if it does IPsec.
378
379	  If unsure, say N.
380
381config INET_ESPINTCP
382	bool "IP: ESP in TCP encapsulation (RFC 8229)"
383	depends on XFRM && INET_ESP
384	select STREAM_PARSER
385	select NET_SOCK_MSG
386	help
387	  Support for RFC 8229 encapsulation of ESP and IKE over
388	  TCP/IPv4 sockets.
389
390	  If unsure, say N.
391
392config INET_IPCOMP
393	tristate "IP: IPComp transformation"
394	select INET_XFRM_TUNNEL
395	select XFRM_IPCOMP
396	---help---
397	  Support for IP Payload Compression Protocol (IPComp) (RFC3173),
398	  typically needed for IPsec.
399
400	  If unsure, say Y.
401
402config INET_XFRM_TUNNEL
403	tristate
404	select INET_TUNNEL
405	default n
406
407config INET_TUNNEL
408	tristate
409	default n
410
411config INET_DIAG
412	tristate "INET: socket monitoring interface"
413	default y
414	---help---
415	  Support for INET (TCP, DCCP, etc) socket monitoring interface used by
416	  native Linux tools such as ss. ss is included in iproute2, currently
417	  downloadable at:
418
419	    http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2
420
421	  If unsure, say Y.
422
423config INET_TCP_DIAG
424	depends on INET_DIAG
425	def_tristate INET_DIAG
426
427config INET_UDP_DIAG
428	tristate "UDP: socket monitoring interface"
429	depends on INET_DIAG && (IPV6 || IPV6=n)
430	default n
431	---help---
432	  Support for UDP socket monitoring interface used by the ss tool.
433	  If unsure, say Y.
434
435config INET_RAW_DIAG
436	tristate "RAW: socket monitoring interface"
437	depends on INET_DIAG && (IPV6 || IPV6=n)
438	default n
439	---help---
440	  Support for RAW socket monitoring interface used by the ss tool.
441	  If unsure, say Y.
442
443config INET_DIAG_DESTROY
444	bool "INET: allow privileged process to administratively close sockets"
445	depends on INET_DIAG
446	default n
447	---help---
448	  Provides a SOCK_DESTROY operation that allows privileged processes
449	  (e.g., a connection manager or a network administration tool such as
450	  ss) to close sockets opened by other processes. Closing a socket in
451	  this way interrupts any blocking read/write/connect operations on
452	  the socket and causes future socket calls to behave as if the socket
453	  had been disconnected.
454	  If unsure, say N.
455
456menuconfig TCP_CONG_ADVANCED
457	bool "TCP: advanced congestion control"
458	---help---
459	  Support for selection of various TCP congestion control
460	  modules.
461
462	  Nearly all users can safely say no here, and a safe default
463	  selection will be made (CUBIC with new Reno as a fallback).
464
465	  If unsure, say N.
466
467if TCP_CONG_ADVANCED
468
469config TCP_CONG_BIC
470	tristate "Binary Increase Congestion (BIC) control"
471	default m
472	---help---
473	  BIC-TCP is a sender-side only change that ensures a linear RTT
474	  fairness under large windows while offering both scalability and
475	  bounded TCP-friendliness. The protocol combines two schemes
476	  called additive increase and binary search increase. When the
477	  congestion window is large, additive increase with a large
478	  increment ensures linear RTT fairness as well as good
479	  scalability. Under small congestion windows, binary search
480	  increase provides TCP friendliness.
481	  See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/
482
483config TCP_CONG_CUBIC
484	tristate "CUBIC TCP"
485	default y
486	---help---
487	  This is version 2.0 of BIC-TCP which uses a cubic growth function
488	  among other techniques.
489	  See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf
490
491config TCP_CONG_WESTWOOD
492	tristate "TCP Westwood+"
493	default m
494	---help---
495	  TCP Westwood+ is a sender-side only modification of the TCP Reno
496	  protocol stack that optimizes the performance of TCP congestion
497	  control. It is based on end-to-end bandwidth estimation to set
498	  congestion window and slow start threshold after a congestion
499	  episode. Using this estimation, TCP Westwood+ adaptively sets a
500	  slow start threshold and a congestion window which takes into
501	  account the bandwidth used  at the time congestion is experienced.
502	  TCP Westwood+ significantly increases fairness wrt TCP Reno in
503	  wired networks and throughput over wireless links.
504
505config TCP_CONG_HTCP
506	tristate "H-TCP"
507	default m
508	---help---
509	  H-TCP is a send-side only modifications of the TCP Reno
510	  protocol stack that optimizes the performance of TCP
511	  congestion control for high speed network links. It uses a
512	  modeswitch to change the alpha and beta parameters of TCP Reno
513	  based on network conditions and in a way so as to be fair with
514	  other Reno and H-TCP flows.
515
516config TCP_CONG_HSTCP
517	tristate "High Speed TCP"
518	default n
519	---help---
520	  Sally Floyd's High Speed TCP (RFC 3649) congestion control.
521	  A modification to TCP's congestion control mechanism for use
522	  with large congestion windows. A table indicates how much to
523	  increase the congestion window by when an ACK is received.
524	  For more detail see http://www.icir.org/floyd/hstcp.html
525
526config TCP_CONG_HYBLA
527	tristate "TCP-Hybla congestion control algorithm"
528	default n
529	---help---
530	  TCP-Hybla is a sender-side only change that eliminates penalization of
531	  long-RTT, large-bandwidth connections, like when satellite legs are
532	  involved, especially when sharing a common bottleneck with normal
533	  terrestrial connections.
534
535config TCP_CONG_VEGAS
536	tristate "TCP Vegas"
537	default n
538	---help---
539	  TCP Vegas is a sender-side only change to TCP that anticipates
540	  the onset of congestion by estimating the bandwidth. TCP Vegas
541	  adjusts the sending rate by modifying the congestion
542	  window. TCP Vegas should provide less packet loss, but it is
543	  not as aggressive as TCP Reno.
544
545config TCP_CONG_NV
546	tristate "TCP NV"
547	default n
548	---help---
549	  TCP NV is a follow up to TCP Vegas. It has been modified to deal with
550	  10G networks, measurement noise introduced by LRO, GRO and interrupt
551	  coalescence. In addition, it will decrease its cwnd multiplicatively
552	  instead of linearly.
553
554	  Note that in general congestion avoidance (cwnd decreased when # packets
555	  queued grows) cannot coexist with congestion control (cwnd decreased only
556	  when there is packet loss) due to fairness issues. One scenario when they
557	  can coexist safely is when the CA flows have RTTs << CC flows RTTs.
558
559	  For further details see http://www.brakmo.org/networking/tcp-nv/
560
561config TCP_CONG_SCALABLE
562	tristate "Scalable TCP"
563	default n
564	---help---
565	  Scalable TCP is a sender-side only change to TCP which uses a
566	  MIMD congestion control algorithm which has some nice scaling
567	  properties, though is known to have fairness issues.
568	  See http://www.deneholme.net/tom/scalable/
569
570config TCP_CONG_LP
571	tristate "TCP Low Priority"
572	default n
573	---help---
574	  TCP Low Priority (TCP-LP), a distributed algorithm whose goal is
575	  to utilize only the excess network bandwidth as compared to the
576	  ``fair share`` of bandwidth as targeted by TCP.
577	  See http://www-ece.rice.edu/networks/TCP-LP/
578
579config TCP_CONG_VENO
580	tristate "TCP Veno"
581	default n
582	---help---
583	  TCP Veno is a sender-side only enhancement of TCP to obtain better
584	  throughput over wireless networks. TCP Veno makes use of state
585	  distinguishing to circumvent the difficult judgment of the packet loss
586	  type. TCP Veno cuts down less congestion window in response to random
587	  loss packets.
588	  See <http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=1177186>
589
590config TCP_CONG_YEAH
591	tristate "YeAH TCP"
592	select TCP_CONG_VEGAS
593	default n
594	---help---
595	  YeAH-TCP is a sender-side high-speed enabled TCP congestion control
596	  algorithm, which uses a mixed loss/delay approach to compute the
597	  congestion window. It's design goals target high efficiency,
598	  internal, RTT and Reno fairness, resilience to link loss while
599	  keeping network elements load as low as possible.
600
601	  For further details look here:
602	    http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf
603
604config TCP_CONG_ILLINOIS
605	tristate "TCP Illinois"
606	default n
607	---help---
608	  TCP-Illinois is a sender-side modification of TCP Reno for
609	  high speed long delay links. It uses round-trip-time to
610	  adjust the alpha and beta parameters to achieve a higher average
611	  throughput and maintain fairness.
612
613	  For further details see:
614	    http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html
615
616config TCP_CONG_DCTCP
617	tristate "DataCenter TCP (DCTCP)"
618	default n
619	---help---
620	  DCTCP leverages Explicit Congestion Notification (ECN) in the network to
621	  provide multi-bit feedback to the end hosts. It is designed to provide:
622
623	  - High burst tolerance (incast due to partition/aggregate),
624	  - Low latency (short flows, queries),
625	  - High throughput (continuous data updates, large file transfers) with
626	    commodity, shallow-buffered switches.
627
628	  All switches in the data center network running DCTCP must support
629	  ECN marking and be configured for marking when reaching defined switch
630	  buffer thresholds. The default ECN marking threshold heuristic for
631	  DCTCP on switches is 20 packets (30KB) at 1Gbps, and 65 packets
632	  (~100KB) at 10Gbps, but might need further careful tweaking.
633
634	  For further details see:
635	    http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf
636
637config TCP_CONG_CDG
638	tristate "CAIA Delay-Gradient (CDG)"
639	default n
640	---help---
641	  CAIA Delay-Gradient (CDG) is a TCP congestion control that modifies
642	  the TCP sender in order to:
643
644	  o Use the delay gradient as a congestion signal.
645	  o Back off with an average probability that is independent of the RTT.
646	  o Coexist with flows that use loss-based congestion control.
647	  o Tolerate packet loss unrelated to congestion.
648
649	  For further details see:
650	    D.A. Hayes and G. Armitage. "Revisiting TCP congestion control using
651	    delay gradients." In Networking 2011. Preprint: http://goo.gl/No3vdg
652
653config TCP_CONG_BBR
654	tristate "BBR TCP"
655	default n
656	---help---
657
658	  BBR (Bottleneck Bandwidth and RTT) TCP congestion control aims to
659	  maximize network utilization and minimize queues. It builds an explicit
660	  model of the the bottleneck delivery rate and path round-trip
661	  propagation delay. It tolerates packet loss and delay unrelated to
662	  congestion. It can operate over LAN, WAN, cellular, wifi, or cable
663	  modem links. It can coexist with flows that use loss-based congestion
664	  control, and can operate with shallow buffers, deep buffers,
665	  bufferbloat, policers, or AQM schemes that do not provide a delay
666	  signal. It requires the fq ("Fair Queue") pacing packet scheduler.
667
668choice
669	prompt "Default TCP congestion control"
670	default DEFAULT_CUBIC
671	help
672	  Select the TCP congestion control that will be used by default
673	  for all connections.
674
675	config DEFAULT_BIC
676		bool "Bic" if TCP_CONG_BIC=y
677
678	config DEFAULT_CUBIC
679		bool "Cubic" if TCP_CONG_CUBIC=y
680
681	config DEFAULT_HTCP
682		bool "Htcp" if TCP_CONG_HTCP=y
683
684	config DEFAULT_HYBLA
685		bool "Hybla" if TCP_CONG_HYBLA=y
686
687	config DEFAULT_VEGAS
688		bool "Vegas" if TCP_CONG_VEGAS=y
689
690	config DEFAULT_VENO
691		bool "Veno" if TCP_CONG_VENO=y
692
693	config DEFAULT_WESTWOOD
694		bool "Westwood" if TCP_CONG_WESTWOOD=y
695
696	config DEFAULT_DCTCP
697		bool "DCTCP" if TCP_CONG_DCTCP=y
698
699	config DEFAULT_CDG
700		bool "CDG" if TCP_CONG_CDG=y
701
702	config DEFAULT_BBR
703		bool "BBR" if TCP_CONG_BBR=y
704
705	config DEFAULT_RENO
706		bool "Reno"
707endchoice
708
709endif
710
711config TCP_CONG_CUBIC
712	tristate
713	depends on !TCP_CONG_ADVANCED
714	default y
715
716config DEFAULT_TCP_CONG
717	string
718	default "bic" if DEFAULT_BIC
719	default "cubic" if DEFAULT_CUBIC
720	default "htcp" if DEFAULT_HTCP
721	default "hybla" if DEFAULT_HYBLA
722	default "vegas" if DEFAULT_VEGAS
723	default "westwood" if DEFAULT_WESTWOOD
724	default "veno" if DEFAULT_VENO
725	default "reno" if DEFAULT_RENO
726	default "dctcp" if DEFAULT_DCTCP
727	default "cdg" if DEFAULT_CDG
728	default "bbr" if DEFAULT_BBR
729	default "cubic"
730
731config TCP_MD5SIG
732	bool "TCP: MD5 Signature Option support (RFC2385)"
733	select CRYPTO
734	select CRYPTO_MD5
735	---help---
736	  RFC2385 specifies a method of giving MD5 protection to TCP sessions.
737	  Its main (only?) use is to protect BGP sessions between core routers
738	  on the Internet.
739
740	  If unsure, say N.
741