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 select INET_TUNNEL 306 select NET_IP_TUNNEL 307 depends on INET_XFRM_MODE_TUNNEL 308 ---help--- 309 Tunneling means encapsulating data of one protocol type within 310 another protocol and sending it over a channel that understands the 311 encapsulating protocol. This can be used with xfrm mode tunnel to give 312 the notion of a secure tunnel for IPSEC and then use routing protocol 313 on top. 314 315config NET_UDP_TUNNEL 316 tristate 317 select NET_IP_TUNNEL 318 default n 319 320config NET_FOU 321 tristate "IP: Foo (IP protocols) over UDP" 322 select XFRM 323 select NET_UDP_TUNNEL 324 ---help--- 325 Foo over UDP allows any IP protocol to be directly encapsulated 326 over UDP include tunnels (IPIP, GRE, SIT). By encapsulating in UDP 327 network mechanisms and optimizations for UDP (such as ECMP 328 and RSS) can be leveraged to provide better service. 329 330config NET_FOU_IP_TUNNELS 331 bool "IP: FOU encapsulation of IP tunnels" 332 depends on NET_IPIP || NET_IPGRE || IPV6_SIT 333 select NET_FOU 334 ---help--- 335 Allow configuration of FOU or GUE encapsulation for IP tunnels. 336 When this option is enabled IP tunnels can be configured to use 337 FOU or GUE encapsulation. 338 339config INET_AH 340 tristate "IP: AH transformation" 341 select XFRM_ALGO 342 select CRYPTO 343 select CRYPTO_HMAC 344 select CRYPTO_MD5 345 select CRYPTO_SHA1 346 ---help--- 347 Support for IPsec AH. 348 349 If unsure, say Y. 350 351config INET_ESP 352 tristate "IP: ESP transformation" 353 select XFRM_ALGO 354 select CRYPTO 355 select CRYPTO_AUTHENC 356 select CRYPTO_HMAC 357 select CRYPTO_MD5 358 select CRYPTO_CBC 359 select CRYPTO_SHA1 360 select CRYPTO_DES 361 select CRYPTO_ECHAINIV 362 ---help--- 363 Support for IPsec ESP. 364 365 If unsure, say Y. 366 367config INET_ESP_OFFLOAD 368 tristate "IP: ESP transformation offload" 369 depends on INET_ESP 370 select XFRM_OFFLOAD 371 default n 372 ---help--- 373 Support for ESP transformation offload. This makes sense 374 only if this system really does IPsec and want to do it 375 with high throughput. A typical desktop system does not 376 need it, even if it does IPsec. 377 378 If unsure, say N. 379 380config INET_IPCOMP 381 tristate "IP: IPComp transformation" 382 select INET_XFRM_TUNNEL 383 select XFRM_IPCOMP 384 ---help--- 385 Support for IP Payload Compression Protocol (IPComp) (RFC3173), 386 typically needed for IPsec. 387 388 If unsure, say Y. 389 390config INET_XFRM_TUNNEL 391 tristate 392 select INET_TUNNEL 393 default n 394 395config INET_TUNNEL 396 tristate 397 default n 398 399config INET_XFRM_MODE_TRANSPORT 400 tristate "IP: IPsec transport mode" 401 default y 402 select XFRM 403 ---help--- 404 Support for IPsec transport mode. 405 406 If unsure, say Y. 407 408config INET_XFRM_MODE_TUNNEL 409 tristate "IP: IPsec tunnel mode" 410 default y 411 select XFRM 412 ---help--- 413 Support for IPsec tunnel mode. 414 415 If unsure, say Y. 416 417config INET_XFRM_MODE_BEET 418 tristate "IP: IPsec BEET mode" 419 default y 420 select XFRM 421 ---help--- 422 Support for IPsec BEET mode. 423 424 If unsure, say Y. 425 426config INET_DIAG 427 tristate "INET: socket monitoring interface" 428 default y 429 ---help--- 430 Support for INET (TCP, DCCP, etc) socket monitoring interface used by 431 native Linux tools such as ss. ss is included in iproute2, currently 432 downloadable at: 433 434 http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2 435 436 If unsure, say Y. 437 438config INET_TCP_DIAG 439 depends on INET_DIAG 440 def_tristate INET_DIAG 441 442config INET_UDP_DIAG 443 tristate "UDP: socket monitoring interface" 444 depends on INET_DIAG && (IPV6 || IPV6=n) 445 default n 446 ---help--- 447 Support for UDP socket monitoring interface used by the ss tool. 448 If unsure, say Y. 449 450config INET_RAW_DIAG 451 tristate "RAW: socket monitoring interface" 452 depends on INET_DIAG && (IPV6 || IPV6=n) 453 default n 454 ---help--- 455 Support for RAW socket monitoring interface used by the ss tool. 456 If unsure, say Y. 457 458config INET_DIAG_DESTROY 459 bool "INET: allow privileged process to administratively close sockets" 460 depends on INET_DIAG 461 default n 462 ---help--- 463 Provides a SOCK_DESTROY operation that allows privileged processes 464 (e.g., a connection manager or a network administration tool such as 465 ss) to close sockets opened by other processes. Closing a socket in 466 this way interrupts any blocking read/write/connect operations on 467 the socket and causes future socket calls to behave as if the socket 468 had been disconnected. 469 If unsure, say N. 470 471menuconfig TCP_CONG_ADVANCED 472 bool "TCP: advanced congestion control" 473 ---help--- 474 Support for selection of various TCP congestion control 475 modules. 476 477 Nearly all users can safely say no here, and a safe default 478 selection will be made (CUBIC with new Reno as a fallback). 479 480 If unsure, say N. 481 482if TCP_CONG_ADVANCED 483 484config TCP_CONG_BIC 485 tristate "Binary Increase Congestion (BIC) control" 486 default m 487 ---help--- 488 BIC-TCP is a sender-side only change that ensures a linear RTT 489 fairness under large windows while offering both scalability and 490 bounded TCP-friendliness. The protocol combines two schemes 491 called additive increase and binary search increase. When the 492 congestion window is large, additive increase with a large 493 increment ensures linear RTT fairness as well as good 494 scalability. Under small congestion windows, binary search 495 increase provides TCP friendliness. 496 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/ 497 498config TCP_CONG_CUBIC 499 tristate "CUBIC TCP" 500 default y 501 ---help--- 502 This is version 2.0 of BIC-TCP which uses a cubic growth function 503 among other techniques. 504 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf 505 506config TCP_CONG_WESTWOOD 507 tristate "TCP Westwood+" 508 default m 509 ---help--- 510 TCP Westwood+ is a sender-side only modification of the TCP Reno 511 protocol stack that optimizes the performance of TCP congestion 512 control. It is based on end-to-end bandwidth estimation to set 513 congestion window and slow start threshold after a congestion 514 episode. Using this estimation, TCP Westwood+ adaptively sets a 515 slow start threshold and a congestion window which takes into 516 account the bandwidth used at the time congestion is experienced. 517 TCP Westwood+ significantly increases fairness wrt TCP Reno in 518 wired networks and throughput over wireless links. 519 520config TCP_CONG_HTCP 521 tristate "H-TCP" 522 default m 523 ---help--- 524 H-TCP is a send-side only modifications of the TCP Reno 525 protocol stack that optimizes the performance of TCP 526 congestion control for high speed network links. It uses a 527 modeswitch to change the alpha and beta parameters of TCP Reno 528 based on network conditions and in a way so as to be fair with 529 other Reno and H-TCP flows. 530 531config TCP_CONG_HSTCP 532 tristate "High Speed TCP" 533 default n 534 ---help--- 535 Sally Floyd's High Speed TCP (RFC 3649) congestion control. 536 A modification to TCP's congestion control mechanism for use 537 with large congestion windows. A table indicates how much to 538 increase the congestion window by when an ACK is received. 539 For more detail see http://www.icir.org/floyd/hstcp.html 540 541config TCP_CONG_HYBLA 542 tristate "TCP-Hybla congestion control algorithm" 543 default n 544 ---help--- 545 TCP-Hybla is a sender-side only change that eliminates penalization of 546 long-RTT, large-bandwidth connections, like when satellite legs are 547 involved, especially when sharing a common bottleneck with normal 548 terrestrial connections. 549 550config TCP_CONG_VEGAS 551 tristate "TCP Vegas" 552 default n 553 ---help--- 554 TCP Vegas is a sender-side only change to TCP that anticipates 555 the onset of congestion by estimating the bandwidth. TCP Vegas 556 adjusts the sending rate by modifying the congestion 557 window. TCP Vegas should provide less packet loss, but it is 558 not as aggressive as TCP Reno. 559 560config TCP_CONG_NV 561 tristate "TCP NV" 562 default n 563 ---help--- 564 TCP NV is a follow up to TCP Vegas. It has been modified to deal with 565 10G networks, measurement noise introduced by LRO, GRO and interrupt 566 coalescence. In addition, it will decrease its cwnd multiplicatively 567 instead of linearly. 568 569 Note that in general congestion avoidance (cwnd decreased when # packets 570 queued grows) cannot coexist with congestion control (cwnd decreased only 571 when there is packet loss) due to fairness issues. One scenario when they 572 can coexist safely is when the CA flows have RTTs << CC flows RTTs. 573 574 For further details see http://www.brakmo.org/networking/tcp-nv/ 575 576config TCP_CONG_SCALABLE 577 tristate "Scalable TCP" 578 default n 579 ---help--- 580 Scalable TCP is a sender-side only change to TCP which uses a 581 MIMD congestion control algorithm which has some nice scaling 582 properties, though is known to have fairness issues. 583 See http://www.deneholme.net/tom/scalable/ 584 585config TCP_CONG_LP 586 tristate "TCP Low Priority" 587 default n 588 ---help--- 589 TCP Low Priority (TCP-LP), a distributed algorithm whose goal is 590 to utilize only the excess network bandwidth as compared to the 591 ``fair share`` of bandwidth as targeted by TCP. 592 See http://www-ece.rice.edu/networks/TCP-LP/ 593 594config TCP_CONG_VENO 595 tristate "TCP Veno" 596 default n 597 ---help--- 598 TCP Veno is a sender-side only enhancement of TCP to obtain better 599 throughput over wireless networks. TCP Veno makes use of state 600 distinguishing to circumvent the difficult judgment of the packet loss 601 type. TCP Veno cuts down less congestion window in response to random 602 loss packets. 603 See <http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=1177186> 604 605config TCP_CONG_YEAH 606 tristate "YeAH TCP" 607 select TCP_CONG_VEGAS 608 default n 609 ---help--- 610 YeAH-TCP is a sender-side high-speed enabled TCP congestion control 611 algorithm, which uses a mixed loss/delay approach to compute the 612 congestion window. It's design goals target high efficiency, 613 internal, RTT and Reno fairness, resilience to link loss while 614 keeping network elements load as low as possible. 615 616 For further details look here: 617 http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf 618 619config TCP_CONG_ILLINOIS 620 tristate "TCP Illinois" 621 default n 622 ---help--- 623 TCP-Illinois is a sender-side modification of TCP Reno for 624 high speed long delay links. It uses round-trip-time to 625 adjust the alpha and beta parameters to achieve a higher average 626 throughput and maintain fairness. 627 628 For further details see: 629 http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html 630 631config TCP_CONG_DCTCP 632 tristate "DataCenter TCP (DCTCP)" 633 default n 634 ---help--- 635 DCTCP leverages Explicit Congestion Notification (ECN) in the network to 636 provide multi-bit feedback to the end hosts. It is designed to provide: 637 638 - High burst tolerance (incast due to partition/aggregate), 639 - Low latency (short flows, queries), 640 - High throughput (continuous data updates, large file transfers) with 641 commodity, shallow-buffered switches. 642 643 All switches in the data center network running DCTCP must support 644 ECN marking and be configured for marking when reaching defined switch 645 buffer thresholds. The default ECN marking threshold heuristic for 646 DCTCP on switches is 20 packets (30KB) at 1Gbps, and 65 packets 647 (~100KB) at 10Gbps, but might need further careful tweaking. 648 649 For further details see: 650 http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf 651 652config TCP_CONG_CDG 653 tristate "CAIA Delay-Gradient (CDG)" 654 default n 655 ---help--- 656 CAIA Delay-Gradient (CDG) is a TCP congestion control that modifies 657 the TCP sender in order to: 658 659 o Use the delay gradient as a congestion signal. 660 o Back off with an average probability that is independent of the RTT. 661 o Coexist with flows that use loss-based congestion control. 662 o Tolerate packet loss unrelated to congestion. 663 664 For further details see: 665 D.A. Hayes and G. Armitage. "Revisiting TCP congestion control using 666 delay gradients." In Networking 2011. Preprint: http://goo.gl/No3vdg 667 668config TCP_CONG_BBR 669 tristate "BBR TCP" 670 default n 671 ---help--- 672 673 BBR (Bottleneck Bandwidth and RTT) TCP congestion control aims to 674 maximize network utilization and minimize queues. It builds an explicit 675 model of the the bottleneck delivery rate and path round-trip 676 propagation delay. It tolerates packet loss and delay unrelated to 677 congestion. It can operate over LAN, WAN, cellular, wifi, or cable 678 modem links. It can coexist with flows that use loss-based congestion 679 control, and can operate with shallow buffers, deep buffers, 680 bufferbloat, policers, or AQM schemes that do not provide a delay 681 signal. It requires the fq ("Fair Queue") pacing packet scheduler. 682 683choice 684 prompt "Default TCP congestion control" 685 default DEFAULT_CUBIC 686 help 687 Select the TCP congestion control that will be used by default 688 for all connections. 689 690 config DEFAULT_BIC 691 bool "Bic" if TCP_CONG_BIC=y 692 693 config DEFAULT_CUBIC 694 bool "Cubic" if TCP_CONG_CUBIC=y 695 696 config DEFAULT_HTCP 697 bool "Htcp" if TCP_CONG_HTCP=y 698 699 config DEFAULT_HYBLA 700 bool "Hybla" if TCP_CONG_HYBLA=y 701 702 config DEFAULT_VEGAS 703 bool "Vegas" if TCP_CONG_VEGAS=y 704 705 config DEFAULT_VENO 706 bool "Veno" if TCP_CONG_VENO=y 707 708 config DEFAULT_WESTWOOD 709 bool "Westwood" if TCP_CONG_WESTWOOD=y 710 711 config DEFAULT_DCTCP 712 bool "DCTCP" if TCP_CONG_DCTCP=y 713 714 config DEFAULT_CDG 715 bool "CDG" if TCP_CONG_CDG=y 716 717 config DEFAULT_BBR 718 bool "BBR" if TCP_CONG_BBR=y 719 720 config DEFAULT_RENO 721 bool "Reno" 722endchoice 723 724endif 725 726config TCP_CONG_CUBIC 727 tristate 728 depends on !TCP_CONG_ADVANCED 729 default y 730 731config DEFAULT_TCP_CONG 732 string 733 default "bic" if DEFAULT_BIC 734 default "cubic" if DEFAULT_CUBIC 735 default "htcp" if DEFAULT_HTCP 736 default "hybla" if DEFAULT_HYBLA 737 default "vegas" if DEFAULT_VEGAS 738 default "westwood" if DEFAULT_WESTWOOD 739 default "veno" if DEFAULT_VENO 740 default "reno" if DEFAULT_RENO 741 default "dctcp" if DEFAULT_DCTCP 742 default "cdg" if DEFAULT_CDG 743 default "bbr" if DEFAULT_BBR 744 default "cubic" 745 746config TCP_MD5SIG 747 bool "TCP: MD5 Signature Option support (RFC2385)" 748 select CRYPTO 749 select CRYPTO_MD5 750 ---help--- 751 RFC2385 specifies a method of giving MD5 protection to TCP sessions. 752 Its main (only?) use is to protect BGP sessions between core routers 753 on the Internet. 754 755 If unsure, say N. 756