1# 2# IP configuration 3# 4config 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/>. For most people, it's safe to say N. 13 14config IP_ADVANCED_ROUTER 15 bool "IP: advanced router" 16 ---help--- 17 If you intend to run your Linux box mostly as a router, i.e. as a 18 computer that forwards and redistributes network packets, say Y; you 19 will then be presented with several options that allow more precise 20 control about the routing process. 21 22 The answer to this question won't directly affect the kernel: 23 answering N will just cause the configurator to skip all the 24 questions about advanced routing. 25 26 Note that your box can only act as a router if you enable IP 27 forwarding in your kernel; you can do that by saying Y to "/proc 28 file system support" and "Sysctl support" below and executing the 29 line 30 31 echo "1" > /proc/sys/net/ipv4/ip_forward 32 33 at boot time after the /proc file system has been mounted. 34 35 If you turn on IP forwarding, you should consider the rp_filter, which 36 automatically rejects incoming packets if the routing table entry 37 for their source address doesn't match the network interface they're 38 arriving on. This has security advantages because it prevents the 39 so-called IP spoofing, however it can pose problems if you use 40 asymmetric routing (packets from you to a host take a different path 41 than packets from that host to you) or if you operate a non-routing 42 host which has several IP addresses on different interfaces. To turn 43 rp_filter on use: 44 45 echo 1 > /proc/sys/net/ipv4/conf/<device>/rp_filter 46 or 47 echo 1 > /proc/sys/net/ipv4/conf/all/rp_filter 48 49 Note that some distributions enable it in startup scripts. 50 For details about rp_filter strict and loose mode read 51 <file:Documentation/networking/ip-sysctl.txt>. 52 53 If unsure, say N here. 54 55config IP_FIB_TRIE_STATS 56 bool "FIB TRIE statistics" 57 depends on IP_ADVANCED_ROUTER 58 ---help--- 59 Keep track of statistics on structure of FIB TRIE table. 60 Useful for testing and measuring TRIE performance. 61 62config IP_MULTIPLE_TABLES 63 bool "IP: policy routing" 64 depends on IP_ADVANCED_ROUTER 65 select FIB_RULES 66 ---help--- 67 Normally, a router decides what to do with a received packet based 68 solely on the packet's final destination address. If you say Y here, 69 the Linux router will also be able to take the packet's source 70 address into account. Furthermore, the TOS (Type-Of-Service) field 71 of the packet can be used for routing decisions as well. 72 73 If you need more information, see the Linux Advanced 74 Routing and Traffic Control documentation at 75 <http://lartc.org/howto/lartc.rpdb.html> 76 77 If unsure, say N. 78 79config IP_ROUTE_MULTIPATH 80 bool "IP: equal cost multipath" 81 depends on IP_ADVANCED_ROUTER 82 help 83 Normally, the routing tables specify a single action to be taken in 84 a deterministic manner for a given packet. If you say Y here 85 however, it becomes possible to attach several actions to a packet 86 pattern, in effect specifying several alternative paths to travel 87 for those packets. The router considers all these paths to be of 88 equal "cost" and chooses one of them in a non-deterministic fashion 89 if a matching packet arrives. 90 91config IP_ROUTE_VERBOSE 92 bool "IP: verbose route monitoring" 93 depends on IP_ADVANCED_ROUTER 94 help 95 If you say Y here, which is recommended, then the kernel will print 96 verbose messages regarding the routing, for example warnings about 97 received packets which look strange and could be evidence of an 98 attack or a misconfigured system somewhere. The information is 99 handled by the klogd daemon which is responsible for kernel messages 100 ("man klogd"). 101 102config IP_ROUTE_CLASSID 103 bool 104 105config IP_PNP 106 bool "IP: kernel level autoconfiguration" 107 help 108 This enables automatic configuration of IP addresses of devices and 109 of the routing table during kernel boot, based on either information 110 supplied on the kernel command line or by BOOTP or RARP protocols. 111 You need to say Y only for diskless machines requiring network 112 access to boot (in which case you want to say Y to "Root file system 113 on NFS" as well), because all other machines configure the network 114 in their startup scripts. 115 116config IP_PNP_DHCP 117 bool "IP: DHCP support" 118 depends on IP_PNP 119 ---help--- 120 If you want your Linux box to mount its whole root file system (the 121 one containing the directory /) from some other computer over the 122 net via NFS and you want the IP address of your computer to be 123 discovered automatically at boot time using the DHCP protocol (a 124 special protocol designed for doing this job), say Y here. In case 125 the boot ROM of your network card was designed for booting Linux and 126 does DHCP itself, providing all necessary information on the kernel 127 command line, you can say N here. 128 129 If unsure, say Y. Note that if you want to use DHCP, a DHCP server 130 must be operating on your network. Read 131 <file:Documentation/filesystems/nfs/nfsroot.txt> for details. 132 133config IP_PNP_BOOTP 134 bool "IP: BOOTP support" 135 depends on IP_PNP 136 ---help--- 137 If you want your Linux box to mount its whole root file system (the 138 one containing the directory /) from some other computer over the 139 net via NFS and you want the IP address of your computer to be 140 discovered automatically at boot time using the BOOTP protocol (a 141 special protocol designed for doing this job), say Y here. In case 142 the boot ROM of your network card was designed for booting Linux and 143 does BOOTP itself, providing all necessary information on the kernel 144 command line, you can say N here. If unsure, say Y. Note that if you 145 want to use BOOTP, a BOOTP server must be operating on your network. 146 Read <file:Documentation/filesystems/nfs/nfsroot.txt> for details. 147 148config IP_PNP_RARP 149 bool "IP: RARP support" 150 depends on IP_PNP 151 help 152 If you want your Linux box to mount its whole root file system (the 153 one containing the directory /) from some other computer over the 154 net via NFS and you want the IP address of your computer to be 155 discovered automatically at boot time using the RARP protocol (an 156 older protocol which is being obsoleted by BOOTP and DHCP), say Y 157 here. Note that if you want to use RARP, a RARP server must be 158 operating on your network. Read 159 <file:Documentation/filesystems/nfs/nfsroot.txt> for details. 160 161config NET_IPIP 162 tristate "IP: tunneling" 163 select INET_TUNNEL 164 select NET_IP_TUNNEL 165 ---help--- 166 Tunneling means encapsulating data of one protocol type within 167 another protocol and sending it over a channel that understands the 168 encapsulating protocol. This particular tunneling driver implements 169 encapsulation of IP within IP, which sounds kind of pointless, but 170 can be useful if you want to make your (or some other) machine 171 appear on a different network than it physically is, or to use 172 mobile-IP facilities (allowing laptops to seamlessly move between 173 networks without changing their IP addresses). 174 175 Saying Y to this option will produce two modules ( = code which can 176 be inserted in and removed from the running kernel whenever you 177 want). Most people won't need this and can say N. 178 179config NET_IPGRE_DEMUX 180 tristate "IP: GRE demultiplexer" 181 help 182 This is helper module to demultiplex GRE packets on GRE version field criteria. 183 Required by ip_gre and pptp modules. 184 185config NET_IP_TUNNEL 186 tristate 187 select DST_CACHE 188 select GRO_CELLS 189 default n 190 191config NET_IPGRE 192 tristate "IP: GRE tunnels over IP" 193 depends on (IPV6 || IPV6=n) && NET_IPGRE_DEMUX 194 select NET_IP_TUNNEL 195 help 196 Tunneling means encapsulating data of one protocol type within 197 another protocol and sending it over a channel that understands the 198 encapsulating protocol. This particular tunneling driver implements 199 GRE (Generic Routing Encapsulation) and at this time allows 200 encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure. 201 This driver is useful if the other endpoint is a Cisco router: Cisco 202 likes GRE much better than the other Linux tunneling driver ("IP 203 tunneling" above). In addition, GRE allows multicast redistribution 204 through the tunnel. 205 206config NET_IPGRE_BROADCAST 207 bool "IP: broadcast GRE over IP" 208 depends on IP_MULTICAST && NET_IPGRE 209 help 210 One application of GRE/IP is to construct a broadcast WAN (Wide Area 211 Network), which looks like a normal Ethernet LAN (Local Area 212 Network), but can be distributed all over the Internet. If you want 213 to do that, say Y here and to "IP multicast routing" below. 214 215config IP_MROUTE_COMMON 216 bool 217 depends on IP_MROUTE || IPV6_MROUTE 218 219config IP_MROUTE 220 bool "IP: multicast routing" 221 depends on IP_MULTICAST 222 select IP_MROUTE_COMMON 223 help 224 This is used if you want your machine to act as a router for IP 225 packets that have several destination addresses. It is needed on the 226 MBONE, a high bandwidth network on top of the Internet which carries 227 audio and video broadcasts. In order to do that, you would most 228 likely run the program mrouted. If you haven't heard about it, you 229 don't need it. 230 231config IP_MROUTE_MULTIPLE_TABLES 232 bool "IP: multicast policy routing" 233 depends on IP_MROUTE && IP_ADVANCED_ROUTER 234 select FIB_RULES 235 help 236 Normally, a multicast router runs a userspace daemon and decides 237 what to do with a multicast packet based on the source and 238 destination addresses. If you say Y here, the multicast router 239 will also be able to take interfaces and packet marks into 240 account and run multiple instances of userspace daemons 241 simultaneously, each one handling a single table. 242 243 If unsure, say N. 244 245config IP_PIMSM_V1 246 bool "IP: PIM-SM version 1 support" 247 depends on IP_MROUTE 248 help 249 Kernel side support for Sparse Mode PIM (Protocol Independent 250 Multicast) version 1. This multicast routing protocol is used widely 251 because Cisco supports it. You need special software to use it 252 (pimd-v1). Please see <http://netweb.usc.edu/pim/> for more 253 information about PIM. 254 255 Say Y if you want to use PIM-SM v1. Note that you can say N here if 256 you just want to use Dense Mode PIM. 257 258config IP_PIMSM_V2 259 bool "IP: PIM-SM version 2 support" 260 depends on IP_MROUTE 261 help 262 Kernel side support for Sparse Mode PIM version 2. In order to use 263 this, you need an experimental routing daemon supporting it (pimd or 264 gated-5). This routing protocol is not used widely, so say N unless 265 you want to play with it. 266 267config SYN_COOKIES 268 bool "IP: TCP syncookie support" 269 ---help--- 270 Normal TCP/IP networking is open to an attack known as "SYN 271 flooding". This denial-of-service attack prevents legitimate remote 272 users from being able to connect to your computer during an ongoing 273 attack and requires very little work from the attacker, who can 274 operate from anywhere on the Internet. 275 276 SYN cookies provide protection against this type of attack. If you 277 say Y here, the TCP/IP stack will use a cryptographic challenge 278 protocol known as "SYN cookies" to enable legitimate users to 279 continue to connect, even when your machine is under attack. There 280 is no need for the legitimate users to change their TCP/IP software; 281 SYN cookies work transparently to them. For technical information 282 about SYN cookies, check out <http://cr.yp.to/syncookies.html>. 283 284 If you are SYN flooded, the source address reported by the kernel is 285 likely to have been forged by the attacker; it is only reported as 286 an aid in tracing the packets to their actual source and should not 287 be taken as absolute truth. 288 289 SYN cookies may prevent correct error reporting on clients when the 290 server is really overloaded. If this happens frequently better turn 291 them off. 292 293 If you say Y here, you can disable SYN cookies at run time by 294 saying Y to "/proc file system support" and 295 "Sysctl support" below and executing the command 296 297 echo 0 > /proc/sys/net/ipv4/tcp_syncookies 298 299 after the /proc file system has been mounted. 300 301 If unsure, say N. 302 303config NET_IPVTI 304 tristate "Virtual (secure) IP: tunneling" 305 depends on IPV6 || IPV6=n 306 select INET_TUNNEL 307 select NET_IP_TUNNEL 308 depends on INET_XFRM_MODE_TUNNEL 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_IPCOMP 382 tristate "IP: IPComp transformation" 383 select INET_XFRM_TUNNEL 384 select XFRM_IPCOMP 385 ---help--- 386 Support for IP Payload Compression Protocol (IPComp) (RFC3173), 387 typically needed for IPsec. 388 389 If unsure, say Y. 390 391config INET_XFRM_TUNNEL 392 tristate 393 select INET_TUNNEL 394 default n 395 396config INET_TUNNEL 397 tristate 398 default n 399 400config INET_XFRM_MODE_TRANSPORT 401 tristate "IP: IPsec transport mode" 402 default y 403 select XFRM 404 ---help--- 405 Support for IPsec transport mode. 406 407 If unsure, say Y. 408 409config INET_XFRM_MODE_TUNNEL 410 tristate "IP: IPsec tunnel mode" 411 default y 412 select XFRM 413 ---help--- 414 Support for IPsec tunnel mode. 415 416 If unsure, say Y. 417 418config INET_XFRM_MODE_BEET 419 tristate "IP: IPsec BEET mode" 420 default y 421 select XFRM 422 ---help--- 423 Support for IPsec BEET mode. 424 425 If unsure, say Y. 426 427config INET_DIAG 428 tristate "INET: socket monitoring interface" 429 default y 430 ---help--- 431 Support for INET (TCP, DCCP, etc) socket monitoring interface used by 432 native Linux tools such as ss. ss is included in iproute2, currently 433 downloadable at: 434 435 http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2 436 437 If unsure, say Y. 438 439config INET_TCP_DIAG 440 depends on INET_DIAG 441 def_tristate INET_DIAG 442 443config INET_UDP_DIAG 444 tristate "UDP: socket monitoring interface" 445 depends on INET_DIAG && (IPV6 || IPV6=n) 446 default n 447 ---help--- 448 Support for UDP socket monitoring interface used by the ss tool. 449 If unsure, say Y. 450 451config INET_RAW_DIAG 452 tristate "RAW: socket monitoring interface" 453 depends on INET_DIAG && (IPV6 || IPV6=n) 454 default n 455 ---help--- 456 Support for RAW socket monitoring interface used by the ss tool. 457 If unsure, say Y. 458 459config INET_DIAG_DESTROY 460 bool "INET: allow privileged process to administratively close sockets" 461 depends on INET_DIAG 462 default n 463 ---help--- 464 Provides a SOCK_DESTROY operation that allows privileged processes 465 (e.g., a connection manager or a network administration tool such as 466 ss) to close sockets opened by other processes. Closing a socket in 467 this way interrupts any blocking read/write/connect operations on 468 the socket and causes future socket calls to behave as if the socket 469 had been disconnected. 470 If unsure, say N. 471 472menuconfig TCP_CONG_ADVANCED 473 bool "TCP: advanced congestion control" 474 ---help--- 475 Support for selection of various TCP congestion control 476 modules. 477 478 Nearly all users can safely say no here, and a safe default 479 selection will be made (CUBIC with new Reno as a fallback). 480 481 If unsure, say N. 482 483if TCP_CONG_ADVANCED 484 485config TCP_CONG_BIC 486 tristate "Binary Increase Congestion (BIC) control" 487 default m 488 ---help--- 489 BIC-TCP is a sender-side only change that ensures a linear RTT 490 fairness under large windows while offering both scalability and 491 bounded TCP-friendliness. The protocol combines two schemes 492 called additive increase and binary search increase. When the 493 congestion window is large, additive increase with a large 494 increment ensures linear RTT fairness as well as good 495 scalability. Under small congestion windows, binary search 496 increase provides TCP friendliness. 497 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/ 498 499config TCP_CONG_CUBIC 500 tristate "CUBIC TCP" 501 default y 502 ---help--- 503 This is version 2.0 of BIC-TCP which uses a cubic growth function 504 among other techniques. 505 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf 506 507config TCP_CONG_WESTWOOD 508 tristate "TCP Westwood+" 509 default m 510 ---help--- 511 TCP Westwood+ is a sender-side only modification of the TCP Reno 512 protocol stack that optimizes the performance of TCP congestion 513 control. It is based on end-to-end bandwidth estimation to set 514 congestion window and slow start threshold after a congestion 515 episode. Using this estimation, TCP Westwood+ adaptively sets a 516 slow start threshold and a congestion window which takes into 517 account the bandwidth used at the time congestion is experienced. 518 TCP Westwood+ significantly increases fairness wrt TCP Reno in 519 wired networks and throughput over wireless links. 520 521config TCP_CONG_HTCP 522 tristate "H-TCP" 523 default m 524 ---help--- 525 H-TCP is a send-side only modifications of the TCP Reno 526 protocol stack that optimizes the performance of TCP 527 congestion control for high speed network links. It uses a 528 modeswitch to change the alpha and beta parameters of TCP Reno 529 based on network conditions and in a way so as to be fair with 530 other Reno and H-TCP flows. 531 532config TCP_CONG_HSTCP 533 tristate "High Speed TCP" 534 default n 535 ---help--- 536 Sally Floyd's High Speed TCP (RFC 3649) congestion control. 537 A modification to TCP's congestion control mechanism for use 538 with large congestion windows. A table indicates how much to 539 increase the congestion window by when an ACK is received. 540 For more detail see http://www.icir.org/floyd/hstcp.html 541 542config TCP_CONG_HYBLA 543 tristate "TCP-Hybla congestion control algorithm" 544 default n 545 ---help--- 546 TCP-Hybla is a sender-side only change that eliminates penalization of 547 long-RTT, large-bandwidth connections, like when satellite legs are 548 involved, especially when sharing a common bottleneck with normal 549 terrestrial connections. 550 551config TCP_CONG_VEGAS 552 tristate "TCP Vegas" 553 default n 554 ---help--- 555 TCP Vegas is a sender-side only change to TCP that anticipates 556 the onset of congestion by estimating the bandwidth. TCP Vegas 557 adjusts the sending rate by modifying the congestion 558 window. TCP Vegas should provide less packet loss, but it is 559 not as aggressive as TCP Reno. 560 561config TCP_CONG_NV 562 tristate "TCP NV" 563 default n 564 ---help--- 565 TCP NV is a follow up to TCP Vegas. It has been modified to deal with 566 10G networks, measurement noise introduced by LRO, GRO and interrupt 567 coalescence. In addition, it will decrease its cwnd multiplicatively 568 instead of linearly. 569 570 Note that in general congestion avoidance (cwnd decreased when # packets 571 queued grows) cannot coexist with congestion control (cwnd decreased only 572 when there is packet loss) due to fairness issues. One scenario when they 573 can coexist safely is when the CA flows have RTTs << CC flows RTTs. 574 575 For further details see http://www.brakmo.org/networking/tcp-nv/ 576 577config TCP_CONG_SCALABLE 578 tristate "Scalable TCP" 579 default n 580 ---help--- 581 Scalable TCP is a sender-side only change to TCP which uses a 582 MIMD congestion control algorithm which has some nice scaling 583 properties, though is known to have fairness issues. 584 See http://www.deneholme.net/tom/scalable/ 585 586config TCP_CONG_LP 587 tristate "TCP Low Priority" 588 default n 589 ---help--- 590 TCP Low Priority (TCP-LP), a distributed algorithm whose goal is 591 to utilize only the excess network bandwidth as compared to the 592 ``fair share`` of bandwidth as targeted by TCP. 593 See http://www-ece.rice.edu/networks/TCP-LP/ 594 595config TCP_CONG_VENO 596 tristate "TCP Veno" 597 default n 598 ---help--- 599 TCP Veno is a sender-side only enhancement of TCP to obtain better 600 throughput over wireless networks. TCP Veno makes use of state 601 distinguishing to circumvent the difficult judgment of the packet loss 602 type. TCP Veno cuts down less congestion window in response to random 603 loss packets. 604 See <http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=1177186> 605 606config TCP_CONG_YEAH 607 tristate "YeAH TCP" 608 select TCP_CONG_VEGAS 609 default n 610 ---help--- 611 YeAH-TCP is a sender-side high-speed enabled TCP congestion control 612 algorithm, which uses a mixed loss/delay approach to compute the 613 congestion window. It's design goals target high efficiency, 614 internal, RTT and Reno fairness, resilience to link loss while 615 keeping network elements load as low as possible. 616 617 For further details look here: 618 http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf 619 620config TCP_CONG_ILLINOIS 621 tristate "TCP Illinois" 622 default n 623 ---help--- 624 TCP-Illinois is a sender-side modification of TCP Reno for 625 high speed long delay links. It uses round-trip-time to 626 adjust the alpha and beta parameters to achieve a higher average 627 throughput and maintain fairness. 628 629 For further details see: 630 http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html 631 632config TCP_CONG_DCTCP 633 tristate "DataCenter TCP (DCTCP)" 634 default n 635 ---help--- 636 DCTCP leverages Explicit Congestion Notification (ECN) in the network to 637 provide multi-bit feedback to the end hosts. It is designed to provide: 638 639 - High burst tolerance (incast due to partition/aggregate), 640 - Low latency (short flows, queries), 641 - High throughput (continuous data updates, large file transfers) with 642 commodity, shallow-buffered switches. 643 644 All switches in the data center network running DCTCP must support 645 ECN marking and be configured for marking when reaching defined switch 646 buffer thresholds. The default ECN marking threshold heuristic for 647 DCTCP on switches is 20 packets (30KB) at 1Gbps, and 65 packets 648 (~100KB) at 10Gbps, but might need further careful tweaking. 649 650 For further details see: 651 http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf 652 653config TCP_CONG_CDG 654 tristate "CAIA Delay-Gradient (CDG)" 655 default n 656 ---help--- 657 CAIA Delay-Gradient (CDG) is a TCP congestion control that modifies 658 the TCP sender in order to: 659 660 o Use the delay gradient as a congestion signal. 661 o Back off with an average probability that is independent of the RTT. 662 o Coexist with flows that use loss-based congestion control. 663 o Tolerate packet loss unrelated to congestion. 664 665 For further details see: 666 D.A. Hayes and G. Armitage. "Revisiting TCP congestion control using 667 delay gradients." In Networking 2011. Preprint: http://goo.gl/No3vdg 668 669config TCP_CONG_BBR 670 tristate "BBR TCP" 671 default n 672 ---help--- 673 674 BBR (Bottleneck Bandwidth and RTT) TCP congestion control aims to 675 maximize network utilization and minimize queues. It builds an explicit 676 model of the the bottleneck delivery rate and path round-trip 677 propagation delay. It tolerates packet loss and delay unrelated to 678 congestion. It can operate over LAN, WAN, cellular, wifi, or cable 679 modem links. It can coexist with flows that use loss-based congestion 680 control, and can operate with shallow buffers, deep buffers, 681 bufferbloat, policers, or AQM schemes that do not provide a delay 682 signal. It requires the fq ("Fair Queue") pacing packet scheduler. 683 684choice 685 prompt "Default TCP congestion control" 686 default DEFAULT_CUBIC 687 help 688 Select the TCP congestion control that will be used by default 689 for all connections. 690 691 config DEFAULT_BIC 692 bool "Bic" if TCP_CONG_BIC=y 693 694 config DEFAULT_CUBIC 695 bool "Cubic" if TCP_CONG_CUBIC=y 696 697 config DEFAULT_HTCP 698 bool "Htcp" if TCP_CONG_HTCP=y 699 700 config DEFAULT_HYBLA 701 bool "Hybla" if TCP_CONG_HYBLA=y 702 703 config DEFAULT_VEGAS 704 bool "Vegas" if TCP_CONG_VEGAS=y 705 706 config DEFAULT_VENO 707 bool "Veno" if TCP_CONG_VENO=y 708 709 config DEFAULT_WESTWOOD 710 bool "Westwood" if TCP_CONG_WESTWOOD=y 711 712 config DEFAULT_DCTCP 713 bool "DCTCP" if TCP_CONG_DCTCP=y 714 715 config DEFAULT_CDG 716 bool "CDG" if TCP_CONG_CDG=y 717 718 config DEFAULT_BBR 719 bool "BBR" if TCP_CONG_BBR=y 720 721 config DEFAULT_RENO 722 bool "Reno" 723endchoice 724 725endif 726 727config TCP_CONG_CUBIC 728 tristate 729 depends on !TCP_CONG_ADVANCED 730 default y 731 732config DEFAULT_TCP_CONG 733 string 734 default "bic" if DEFAULT_BIC 735 default "cubic" if DEFAULT_CUBIC 736 default "htcp" if DEFAULT_HTCP 737 default "hybla" if DEFAULT_HYBLA 738 default "vegas" if DEFAULT_VEGAS 739 default "westwood" if DEFAULT_WESTWOOD 740 default "veno" if DEFAULT_VENO 741 default "reno" if DEFAULT_RENO 742 default "dctcp" if DEFAULT_DCTCP 743 default "cdg" if DEFAULT_CDG 744 default "bbr" if DEFAULT_BBR 745 default "cubic" 746 747config TCP_MD5SIG 748 bool "TCP: MD5 Signature Option support (RFC2385)" 749 select CRYPTO 750 select CRYPTO_MD5 751 ---help--- 752 RFC2385 specifies a method of giving MD5 protection to TCP sessions. 753 Its main (only?) use is to protect BGP sessions between core routers 754 on the Internet. 755 756 If unsure, say N. 757