net/ipv4/Kconfig

   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-itg.lbl.gov/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.
  16
  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.
  24
  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.
  28
  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
  33
  34           echo "1" > /proc/sys/net/ipv4/ip_forward
  35
  36           at boot time after the /proc file system has been mounted.
  37
  38           If you turn on IP forwarding, you will also get the rp_filter, which
  39           automatically rejects incoming packets if the routing table entry
  40           for their source address doesn't match the network interface they're
  41           arriving on. This has security advantages because it prevents the
  42           so-called IP spoofing, however it can pose problems if you use
  43           asymmetric routing (packets from you to a host take a different path
  44           than packets from that host to you) or if you operate a non-routing
  45           host which has several IP addresses on different interfaces. To turn
  46           rp_filter off use:
  47
  48           echo 0 > /proc/sys/net/ipv4/conf/<device>/rp_filter
  49           or
  50           echo 0 > /proc/sys/net/ipv4/conf/all/rp_filter
  51
  52           If unsure, say N here.
  53
  54 choice
  55         prompt "Choose IP: FIB lookup algorithm (choose FIB_HASH if unsure)"
  56         depends on IP_ADVANCED_ROUTER
  57         default ASK_IP_FIB_HASH
  58
  59 config ASK_IP_FIB_HASH
  60         bool "FIB_HASH"
  61         ---help---
  62         Current FIB is very proven and good enough for most users.
  63
  64 config IP_FIB_TRIE
  65         bool "FIB_TRIE"
  66         ---help---
  67         Use new experimental LC-trie as FIB lookup algorithm.
  68         This improves lookup performance if you have a large
  69         number of routes.
  70
  71         LC-trie is a longest matching prefix lookup algorithm which
  72         performs better than FIB_HASH for large routing tables.
  73         But, it consumes more memory and is more complex.
  74
  75         LC-trie is described in:
  76
  77         IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
  78         IEEE Journal on Selected Areas in Communications, 17(6):1083-1092, June 1999
  79         An experimental study of compression methods for dynamic tries
  80         Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
  81         http://www.nada.kth.se/~snilsson/public/papers/dyntrie2/
  82
  83 endchoice
  84
  85 config IP_FIB_HASH
  86         def_bool ASK_IP_FIB_HASH || !IP_ADVANCED_ROUTER
  87
  88 config IP_MULTIPLE_TABLES
  89         bool "IP: policy routing"
  90         depends on IP_ADVANCED_ROUTER
  91         select FIB_RULES
  92         ---help---
  93           Normally, a router decides what to do with a received packet based
  94           solely on the packet's final destination address. If you say Y here,
  95           the Linux router will also be able to take the packet's source
  96           address into account. Furthermore, the TOS (Type-Of-Service) field
  97           of the packet can be used for routing decisions as well.
  98
  99           If you are interested in this, please see the preliminary
 100           documentation at <http://www.compendium.com.ar/policy-routing.txt>
 101           and <ftp://post.tepkom.ru/pub/vol2/Linux/docs/advanced-routing.tex>.
 102           You will need supporting software from
 103           <ftp://ftp.tux.org/pub/net/ip-routing/>.
 104
 105           If unsure, say N.
 106
 107 config IP_ROUTE_FWMARK
 108         bool "IP: use netfilter MARK value as routing key"
 109         depends on IP_MULTIPLE_TABLES && NETFILTER
 110         help
 111           If you say Y here, you will be able to specify different routes for
 112           packets with different mark values (see iptables(8), MARK target).
 113
 114 config IP_ROUTE_MULTIPATH
 115         bool "IP: equal cost multipath"
 116         depends on IP_ADVANCED_ROUTER
 117         help
 118           Normally, the routing tables specify a single action to be taken in
 119           a deterministic manner for a given packet. If you say Y here
 120           however, it becomes possible to attach several actions to a packet
 121           pattern, in effect specifying several alternative paths to travel
 122           for those packets. The router considers all these paths to be of
 123           equal "cost" and chooses one of them in a non-deterministic fashion
 124           if a matching packet arrives.
 125
 126 config IP_ROUTE_MULTIPATH_CACHED
 127         bool "IP: equal cost multipath with caching support (EXPERIMENTAL)"
 128         depends on IP_ROUTE_MULTIPATH
 129         help
 130           Normally, equal cost multipath routing is not supported by the
 131           routing cache. If you say Y here, alternative routes are cached
 132           and on cache lookup a route is chosen in a configurable fashion.
 133
 134           If unsure, say N.
 135
 136 config IP_ROUTE_MULTIPATH_RR
 137         tristate "MULTIPATH: round robin algorithm"
 138         depends on IP_ROUTE_MULTIPATH_CACHED
 139         help
 140           Mulitpath routes are chosen according to Round Robin
 141
 142 config IP_ROUTE_MULTIPATH_RANDOM
 143         tristate "MULTIPATH: random algorithm"
 144         depends on IP_ROUTE_MULTIPATH_CACHED
 145         help
 146           Multipath routes are chosen in a random fashion. Actually,
 147           there is no weight for a route. The advantage of this policy
 148           is that it is implemented stateless and therefore introduces only
 149           a very small delay.
 150
 151 config IP_ROUTE_MULTIPATH_WRANDOM
 152         tristate "MULTIPATH: weighted random algorithm"
 153         depends on IP_ROUTE_MULTIPATH_CACHED
 154         help
 155           Multipath routes are chosen in a weighted random fashion.
 156           The per route weights are the weights visible via ip route 2. As the
 157           corresponding state management introduces some overhead routing delay
 158           is increased.
 159
 160 config IP_ROUTE_MULTIPATH_DRR
 161         tristate "MULTIPATH: interface round robin algorithm"
 162         depends on IP_ROUTE_MULTIPATH_CACHED
 163         help
 164           Connections are distributed in a round robin fashion over the
 165           available interfaces. This policy makes sense if the connections
 166           should be primarily distributed on interfaces and not on routes.
 167
 168 config IP_ROUTE_VERBOSE
 169         bool "IP: verbose route monitoring"
 170         depends on IP_ADVANCED_ROUTER
 171         help
 172           If you say Y here, which is recommended, then the kernel will print
 173           verbose messages regarding the routing, for example warnings about
 174           received packets which look strange and could be evidence of an
 175           attack or a misconfigured system somewhere. The information is
 176           handled by the klogd daemon which is responsible for kernel messages
 177           ("man klogd").
 178
 179 config IP_PNP
 180         bool "IP: kernel level autoconfiguration"
 181         help
 182           This enables automatic configuration of IP addresses of devices and
 183           of the routing table during kernel boot, based on either information
 184           supplied on the kernel command line or by BOOTP or RARP protocols.
 185           You need to say Y only for diskless machines requiring network
 186           access to boot (in which case you want to say Y to "Root file system
 187           on NFS" as well), because all other machines configure the network
 188           in their startup scripts.
 189
 190 config IP_PNP_DHCP
 191         bool "IP: DHCP support"
 192         depends on IP_PNP
 193         ---help---
 194           If you want your Linux box to mount its whole root file system (the
 195           one containing the directory /) from some other computer over the
 196           net via NFS and you want the IP address of your computer to be
 197           discovered automatically at boot time using the DHCP protocol (a
 198           special protocol designed for doing this job), say Y here. In case
 199           the boot ROM of your network card was designed for booting Linux and
 200           does DHCP itself, providing all necessary information on the kernel
 201           command line, you can say N here.
 202
 203           If unsure, say Y. Note that if you want to use DHCP, a DHCP server
 204           must be operating on your network.  Read
 205           <file:Documentation/nfsroot.txt> for details.
 206
 207 config IP_PNP_BOOTP
 208         bool "IP: BOOTP support"
 209         depends on IP_PNP
 210         ---help---
 211           If you want your Linux box to mount its whole root file system (the
 212           one containing the directory /) from some other computer over the
 213           net via NFS and you want the IP address of your computer to be
 214           discovered automatically at boot time using the BOOTP protocol (a
 215           special protocol designed for doing this job), say Y here. In case
 216           the boot ROM of your network card was designed for booting Linux and
 217           does BOOTP itself, providing all necessary information on the kernel
 218           command line, you can say N here. If unsure, say Y. Note that if you
 219           want to use BOOTP, a BOOTP server must be operating on your network.
 220           Read <file:Documentation/nfsroot.txt> for details.
 221
 222 config IP_PNP_RARP
 223         bool "IP: RARP support"
 224         depends on IP_PNP
 225         help
 226           If you want your Linux box to mount its whole root file system (the
 227           one containing the directory /) from some other computer over the
 228           net via NFS and you want the IP address of your computer to be
 229           discovered automatically at boot time using the RARP protocol (an
 230           older protocol which is being obsoleted by BOOTP and DHCP), say Y
 231           here. Note that if you want to use RARP, a RARP server must be
 232           operating on your network. Read <file:Documentation/nfsroot.txt> for
 233           details.
 234
 235 # not yet ready..
 236 #   bool '    IP: ARP support' CONFIG_IP_PNP_ARP
 237 config NET_IPIP
 238         tristate "IP: tunneling"
 239         select INET_TUNNEL
 240         ---help---
 241           Tunneling means encapsulating data of one protocol type within
 242           another protocol and sending it over a channel that understands the
 243           encapsulating protocol. This particular tunneling driver implements
 244           encapsulation of IP within IP, which sounds kind of pointless, but
 245           can be useful if you want to make your (or some other) machine
 246           appear on a different network than it physically is, or to use
 247           mobile-IP facilities (allowing laptops to seamlessly move between
 248           networks without changing their IP addresses).
 249
 250           Saying Y to this option will produce two modules ( = code which can
 251           be inserted in and removed from the running kernel whenever you
 252           want). Most people won't need this and can say N.
 253
 254 config NET_IPGRE
 255         tristate "IP: GRE tunnels over IP"
 256         help
 257           Tunneling means encapsulating data of one protocol type within
 258           another protocol and sending it over a channel that understands the
 259           encapsulating protocol. This particular tunneling driver implements
 260           GRE (Generic Routing Encapsulation) and at this time allows
 261           encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure.
 262           This driver is useful if the other endpoint is a Cisco router: Cisco
 263           likes GRE much better than the other Linux tunneling driver ("IP
 264           tunneling" above). In addition, GRE allows multicast redistribution
 265           through the tunnel.
 266
 267 config NET_IPGRE_BROADCAST
 268         bool "IP: broadcast GRE over IP"
 269         depends on IP_MULTICAST && NET_IPGRE
 270         help
 271           One application of GRE/IP is to construct a broadcast WAN (Wide Area
 272           Network), which looks like a normal Ethernet LAN (Local Area
 273           Network), but can be distributed all over the Internet. If you want
 274           to do that, say Y here and to "IP multicast routing" below.
 275
 276 config IP_MROUTE
 277         bool "IP: multicast routing"
 278         depends on IP_MULTICAST
 279         help
 280           This is used if you want your machine to act as a router for IP
 281           packets that have several destination addresses. It is needed on the
 282           MBONE, a high bandwidth network on top of the Internet which carries
 283           audio and video broadcasts. In order to do that, you would most
 284           likely run the program mrouted. Information about the multicast
 285           capabilities of the various network cards is contained in
 286           <file:Documentation/networking/multicast.txt>. If you haven't heard
 287           about it, you don't need it.
 288
 289 config IP_PIMSM_V1
 290         bool "IP: PIM-SM version 1 support"
 291         depends on IP_MROUTE
 292         help
 293           Kernel side support for Sparse Mode PIM (Protocol Independent
 294           Multicast) version 1. This multicast routing protocol is used widely
 295           because Cisco supports it. You need special software to use it
 296           (pimd-v1). Please see <http://netweb.usc.edu/pim/> for more
 297           information about PIM.
 298
 299           Say Y if you want to use PIM-SM v1. Note that you can say N here if
 300           you just want to use Dense Mode PIM.
 301
 302 config IP_PIMSM_V2
 303         bool "IP: PIM-SM version 2 support"
 304         depends on IP_MROUTE
 305         help
 306           Kernel side support for Sparse Mode PIM version 2. In order to use
 307           this, you need an experimental routing daemon supporting it (pimd or
 308           gated-5). This routing protocol is not used widely, so say N unless
 309           you want to play with it.
 310
 311 config ARPD
 312         bool "IP: ARP daemon support (EXPERIMENTAL)"
 313         depends on EXPERIMENTAL
 314         ---help---
 315           Normally, the kernel maintains an internal cache which maps IP
 316           addresses to hardware addresses on the local network, so that
 317           Ethernet/Token Ring/ etc. frames are sent to the proper address on
 318           the physical networking layer. For small networks having a few
 319           hundred directly connected hosts or less, keeping this address
 320           resolution (ARP) cache inside the kernel works well. However,
 321           maintaining an internal ARP cache does not work well for very large
 322           switched networks, and will use a lot of kernel memory if TCP/IP
 323           connections are made to many machines on the network.
 324
 325           If you say Y here, the kernel's internal ARP cache will never grow
 326           to more than 256 entries (the oldest entries are expired in a LIFO
 327           manner) and communication will be attempted with the user space ARP
 328           daemon arpd. Arpd then answers the address resolution request either
 329           from its own cache or by asking the net.
 330
 331           This code is experimental and also obsolete. If you want to use it,
 332           you need to find a version of the daemon arpd on the net somewhere,
 333           and you should also say Y to "Kernel/User network link driver",
 334           below. If unsure, say N.
 335
 336 config SYN_COOKIES
 337         bool "IP: TCP syncookie support (disabled per default)"
 338         ---help---
 339           Normal TCP/IP networking is open to an attack known as "SYN
 340           flooding". This denial-of-service attack prevents legitimate remote
 341           users from being able to connect to your computer during an ongoing
 342           attack and requires very little work from the attacker, who can
 343           operate from anywhere on the Internet.
 344
 345           SYN cookies provide protection against this type of attack. If you
 346           say Y here, the TCP/IP stack will use a cryptographic challenge
 347           protocol known as "SYN cookies" to enable legitimate users to
 348           continue to connect, even when your machine is under attack. There
 349           is no need for the legitimate users to change their TCP/IP software;
 350           SYN cookies work transparently to them. For technical information
 351           about SYN cookies, check out <http://cr.yp.to/syncookies.html>.
 352
 353           If you are SYN flooded, the source address reported by the kernel is
 354           likely to have been forged by the attacker; it is only reported as
 355           an aid in tracing the packets to their actual source and should not
 356           be taken as absolute truth.
 357
 358           SYN cookies may prevent correct error reporting on clients when the
 359           server is really overloaded. If this happens frequently better turn
 360           them off.
 361
 362           If you say Y here, note that SYN cookies aren't enabled by default;
 363           you can enable them by saying Y to "/proc file system support" and
 364           "Sysctl support" below and executing the command
 365
 366           echo 1 >/proc/sys/net/ipv4/tcp_syncookies
 367
 368           at boot time after the /proc file system has been mounted.
 369
 370           If unsure, say N.
 371
 372 config INET_AH
 373         tristate "IP: AH transformation"
 374         select XFRM
 375         select CRYPTO
 376         select CRYPTO_HMAC
 377         select CRYPTO_MD5
 378         select CRYPTO_SHA1
 379         ---help---
 380           Support for IPsec AH.
 381
 382           If unsure, say Y.
 383
 384 config INET_ESP
 385         tristate "IP: ESP transformation"
 386         select XFRM
 387         select CRYPTO
 388         select CRYPTO_HMAC
 389         select CRYPTO_MD5
 390         select CRYPTO_CBC
 391         select CRYPTO_SHA1
 392         select CRYPTO_DES
 393         ---help---
 394           Support for IPsec ESP.
 395
 396           If unsure, say Y.
 397
 398 config INET_IPCOMP
 399         tristate "IP: IPComp transformation"
 400         select XFRM
 401         select INET_XFRM_TUNNEL
 402         select CRYPTO
 403         select CRYPTO_DEFLATE
 404         ---help---
 405           Support for IP Payload Compression Protocol (IPComp) (RFC3173),
 406           typically needed for IPsec.
 407
 408           If unsure, say Y.
 409
 410 config INET_XFRM_TUNNEL
 411         tristate
 412         select INET_TUNNEL
 413         default n
 414
 415 config INET_TUNNEL
 416         tristate
 417         default n
 418
 419 config INET_XFRM_MODE_TRANSPORT
 420         tristate "IP: IPsec transport mode"
 421         default y
 422         select XFRM
 423         ---help---
 424           Support for IPsec transport mode.
 425
 426           If unsure, say Y.
 427
 428 config INET_XFRM_MODE_TUNNEL
 429         tristate "IP: IPsec tunnel mode"
 430         default y
 431         select XFRM
 432         ---help---
 433           Support for IPsec tunnel mode.
 434
 435           If unsure, say Y.
 436
 437 config INET_XFRM_MODE_BEET
 438         tristate "IP: IPsec BEET mode"
 439         default y
 440         select XFRM
 441         ---help---
 442           Support for IPsec BEET mode.
 443
 444           If unsure, say Y.
 445
 446 config INET_DIAG
 447         tristate "INET: socket monitoring interface"
 448         default y
 449         ---help---
 450           Support for INET (TCP, DCCP, etc) socket monitoring interface used by
 451           native Linux tools such as ss. ss is included in iproute2, currently
 452           downloadable at <http://developer.osdl.org/dev/iproute2>.
 453
 454           If unsure, say Y.
 455
 456 config INET_TCP_DIAG
 457         depends on INET_DIAG
 458         def_tristate INET_DIAG
 459
 460 menuconfig TCP_CONG_ADVANCED
 461         bool "TCP: advanced congestion control"
 462         ---help---
 463           Support for selection of various TCP congestion control
 464           modules.
 465
 466           Nearly all users can safely say no here, and a safe default
 467           selection will be made (CUBIC with new Reno as a fallback).
 468
 469           If unsure, say N.
 470
 471 if TCP_CONG_ADVANCED
 472
 473 config TCP_CONG_BIC
 474         tristate "Binary Increase Congestion (BIC) control"
 475         default m
 476         ---help---
 477         BIC-TCP is a sender-side only change that ensures a linear RTT
 478         fairness under large windows while offering both scalability and
 479         bounded TCP-friendliness. The protocol combines two schemes
 480         called additive increase and binary search increase. When the
 481         congestion window is large, additive increase with a large
 482         increment ensures linear RTT fairness as well as good
 483         scalability. Under small congestion windows, binary search
 484         increase provides TCP friendliness.
 485         See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/
 486
 487 config TCP_CONG_CUBIC
 488         tristate "CUBIC TCP"
 489         default y
 490         ---help---
 491         This is version 2.0 of BIC-TCP which uses a cubic growth function
 492         among other techniques.
 493         See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf
 494
 495 config TCP_CONG_WESTWOOD
 496         tristate "TCP Westwood+"
 497         default m
 498         ---help---
 499         TCP Westwood+ is a sender-side only modification of the TCP Reno
 500         protocol stack that optimizes the performance of TCP congestion
 501         control. It is based on end-to-end bandwidth estimation to set
 502         congestion window and slow start threshold after a congestion
 503         episode. Using this estimation, TCP Westwood+ adaptively sets a
 504         slow start threshold and a congestion window which takes into
 505         account the bandwidth used  at the time congestion is experienced.
 506         TCP Westwood+ significantly increases fairness wrt TCP Reno in
 507         wired networks and throughput over wireless links.
 508
 509 config TCP_CONG_HTCP
 510         tristate "H-TCP"
 511         default m
 512         ---help---
 513         H-TCP is a send-side only modifications of the TCP Reno
 514         protocol stack that optimizes the performance of TCP
 515         congestion control for high speed network links. It uses a
 516         modeswitch to change the alpha and beta parameters of TCP Reno
 517         based on network conditions and in a way so as to be fair with
 518         other Reno and H-TCP flows.
 519
 520 config TCP_CONG_HSTCP
 521         tristate "High Speed TCP"
 522         depends on EXPERIMENTAL
 523         default n
 524         ---help---
 525         Sally Floyd's High Speed TCP (RFC 3649) congestion control.
 526         A modification to TCP's congestion control mechanism for use
 527         with large congestion windows. A table indicates how much to
 528         increase the congestion window by when an ACK is received.
 529         For more detail see http://www.icir.org/floyd/hstcp.html
 530
 531 config TCP_CONG_HYBLA
 532         tristate "TCP-Hybla congestion control algorithm"
 533         depends on EXPERIMENTAL
 534         default n
 535         ---help---
 536         TCP-Hybla is a sender-side only change that eliminates penalization of
 537         long-RTT, large-bandwidth connections, like when satellite legs are
 538         involved, especially when sharing a common bottleneck with normal
 539         terrestrial connections.
 540
 541 config TCP_CONG_VEGAS
 542         tristate "TCP Vegas"
 543         depends on EXPERIMENTAL
 544         default n
 545         ---help---
 546         TCP Vegas is a sender-side only change to TCP that anticipates
 547         the onset of congestion by estimating the bandwidth. TCP Vegas
 548         adjusts the sending rate by modifying the congestion
 549         window. TCP Vegas should provide less packet loss, but it is
 550         not as aggressive as TCP Reno.
 551
 552 config TCP_CONG_SCALABLE
 553         tristate "Scalable TCP"
 554         depends on EXPERIMENTAL
 555         default n
 556         ---help---
 557         Scalable TCP is a sender-side only change to TCP which uses a
 558         MIMD congestion control algorithm which has some nice scaling
 559         properties, though is known to have fairness issues.
 560         See http://www-lce.eng.cam.ac.uk/~ctk21/scalable/
 561
 562 config TCP_CONG_LP
 563         tristate "TCP Low Priority"
 564         depends on EXPERIMENTAL
 565         default n
 566         ---help---
 567         TCP Low Priority (TCP-LP), a distributed algorithm whose goal is
 568         to utilize only the excess network bandwidth as compared to the
 569         ``fair share`` of bandwidth as targeted by TCP.
 570         See http://www-ece.rice.edu/networks/TCP-LP/
 571
 572 config TCP_CONG_VENO
 573         tristate "TCP Veno"
 574         depends on EXPERIMENTAL
 575         default n
 576         ---help---
 577         TCP Veno is a sender-side only enhancement of TCP to obtain better
 578         throughput over wireless networks. TCP Veno makes use of state
 579         distinguishing to circumvent the difficult judgment of the packet loss
 580         type. TCP Veno cuts down less congestion window in response to random
 581         loss packets.
 582         See http://www.ntu.edu.sg/home5/ZHOU0022/papers/CPFu03a.pdf
 583
 584 choice
 585         prompt "Default TCP congestion control"
 586         default DEFAULT_CUBIC
 587         help
 588           Select the TCP congestion control that will be used by default
 589           for all connections.
 590
 591         config DEFAULT_BIC
 592                 bool "Bic" if TCP_CONG_BIC=y
 593
 594         config DEFAULT_CUBIC
 595                 bool "Cubic" if TCP_CONG_CUBIC=y
 596
 597         config DEFAULT_HTCP
 598                 bool "Htcp" if TCP_CONG_HTCP=y
 599
 600         config DEFAULT_VEGAS
 601                 bool "Vegas" if TCP_CONG_VEGAS=y
 602
 603         config DEFAULT_WESTWOOD
 604                 bool "Westwood" if TCP_CONG_WESTWOOD=y
 605
 606         config DEFAULT_RENO
 607                 bool "Reno"
 608
 609 endchoice
 610
 611 endif
 612
 613 config TCP_CONG_CUBIC
 614         tristate
 615         depends on !TCP_CONG_ADVANCED
 616         default y
 617
 618 config DEFAULT_TCP_CONG
 619         string
 620         default "bic" if DEFAULT_BIC
 621         default "cubic" if DEFAULT_CUBIC
 622         default "htcp" if DEFAULT_HTCP
 623         default "vegas" if DEFAULT_VEGAS
 624         default "westwood" if DEFAULT_WESTWOOD
 625         default "reno" if DEFAULT_RENO
 626         default "cubic"
 627
 628 source "net/ipv4/ipvs/Kconfig"
 629