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 are interested in this, please see the preliminary 74 documentation at <http://www.compendium.com.ar/policy-routing.txt> 75 and <ftp://post.tepkom.ru/pub/vol2/Linux/docs/advanced-routing.tex>. 76 You will need supporting software from 77 <ftp://ftp.tux.org/pub/net/ip-routing/>. 78 79 If unsure, say N. 80 81config IP_ROUTE_MULTIPATH 82 bool "IP: equal cost multipath" 83 depends on IP_ADVANCED_ROUTER 84 help 85 Normally, the routing tables specify a single action to be taken in 86 a deterministic manner for a given packet. If you say Y here 87 however, it becomes possible to attach several actions to a packet 88 pattern, in effect specifying several alternative paths to travel 89 for those packets. The router considers all these paths to be of 90 equal "cost" and chooses one of them in a non-deterministic fashion 91 if a matching packet arrives. 92 93config IP_ROUTE_VERBOSE 94 bool "IP: verbose route monitoring" 95 depends on IP_ADVANCED_ROUTER 96 help 97 If you say Y here, which is recommended, then the kernel will print 98 verbose messages regarding the routing, for example warnings about 99 received packets which look strange and could be evidence of an 100 attack or a misconfigured system somewhere. The information is 101 handled by the klogd daemon which is responsible for kernel messages 102 ("man klogd"). 103 104config IP_ROUTE_CLASSID 105 bool 106 107config IP_PNP 108 bool "IP: kernel level autoconfiguration" 109 help 110 This enables automatic configuration of IP addresses of devices and 111 of the routing table during kernel boot, based on either information 112 supplied on the kernel command line or by BOOTP or RARP protocols. 113 You need to say Y only for diskless machines requiring network 114 access to boot (in which case you want to say Y to "Root file system 115 on NFS" as well), because all other machines configure the network 116 in their startup scripts. 117 118config IP_PNP_DHCP 119 bool "IP: DHCP support" 120 depends on IP_PNP 121 ---help--- 122 If you want your Linux box to mount its whole root file system (the 123 one containing the directory /) from some other computer over the 124 net via NFS and you want the IP address of your computer to be 125 discovered automatically at boot time using the DHCP protocol (a 126 special protocol designed for doing this job), say Y here. In case 127 the boot ROM of your network card was designed for booting Linux and 128 does DHCP itself, providing all necessary information on the kernel 129 command line, you can say N here. 130 131 If unsure, say Y. Note that if you want to use DHCP, a DHCP server 132 must be operating on your network. Read 133 <file:Documentation/filesystems/nfs/nfsroot.txt> for details. 134 135config IP_PNP_BOOTP 136 bool "IP: BOOTP support" 137 depends on IP_PNP 138 ---help--- 139 If you want your Linux box to mount its whole root file system (the 140 one containing the directory /) from some other computer over the 141 net via NFS and you want the IP address of your computer to be 142 discovered automatically at boot time using the BOOTP protocol (a 143 special protocol designed for doing this job), say Y here. In case 144 the boot ROM of your network card was designed for booting Linux and 145 does BOOTP itself, providing all necessary information on the kernel 146 command line, you can say N here. If unsure, say Y. Note that if you 147 want to use BOOTP, a BOOTP server must be operating on your network. 148 Read <file:Documentation/filesystems/nfs/nfsroot.txt> for details. 149 150config IP_PNP_RARP 151 bool "IP: RARP support" 152 depends on IP_PNP 153 help 154 If you want your Linux box to mount its whole root file system (the 155 one containing the directory /) from some other computer over the 156 net via NFS and you want the IP address of your computer to be 157 discovered automatically at boot time using the RARP protocol (an 158 older protocol which is being obsoleted by BOOTP and DHCP), say Y 159 here. Note that if you want to use RARP, a RARP server must be 160 operating on your network. Read 161 <file:Documentation/filesystems/nfs/nfsroot.txt> for details. 162 163config NET_IPIP 164 tristate "IP: tunneling" 165 select INET_TUNNEL 166 select NET_IP_TUNNEL 167 ---help--- 168 Tunneling means encapsulating data of one protocol type within 169 another protocol and sending it over a channel that understands the 170 encapsulating protocol. This particular tunneling driver implements 171 encapsulation of IP within IP, which sounds kind of pointless, but 172 can be useful if you want to make your (or some other) machine 173 appear on a different network than it physically is, or to use 174 mobile-IP facilities (allowing laptops to seamlessly move between 175 networks without changing their IP addresses). 176 177 Saying Y to this option will produce two modules ( = code which can 178 be inserted in and removed from the running kernel whenever you 179 want). Most people won't need this and can say N. 180 181config NET_IPGRE_DEMUX 182 tristate "IP: GRE demultiplexer" 183 help 184 This is helper module to demultiplex GRE packets on GRE version field criteria. 185 Required by ip_gre and pptp modules. 186 187config NET_IP_TUNNEL 188 tristate 189 select DST_CACHE 190 select GRO_CELLS 191 default n 192 193config NET_IPGRE 194 tristate "IP: GRE tunnels over IP" 195 depends on (IPV6 || IPV6=n) && NET_IPGRE_DEMUX 196 select NET_IP_TUNNEL 197 help 198 Tunneling means encapsulating data of one protocol type within 199 another protocol and sending it over a channel that understands the 200 encapsulating protocol. This particular tunneling driver implements 201 GRE (Generic Routing Encapsulation) and at this time allows 202 encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure. 203 This driver is useful if the other endpoint is a Cisco router: Cisco 204 likes GRE much better than the other Linux tunneling driver ("IP 205 tunneling" above). In addition, GRE allows multicast redistribution 206 through the tunnel. 207 208config NET_IPGRE_BROADCAST 209 bool "IP: broadcast GRE over IP" 210 depends on IP_MULTICAST && NET_IPGRE 211 help 212 One application of GRE/IP is to construct a broadcast WAN (Wide Area 213 Network), which looks like a normal Ethernet LAN (Local Area 214 Network), but can be distributed all over the Internet. If you want 215 to do that, say Y here and to "IP multicast routing" below. 216 217config IP_MROUTE 218 bool "IP: multicast routing" 219 depends on IP_MULTICAST 220 help 221 This is used if you want your machine to act as a router for IP 222 packets that have several destination addresses. It is needed on the 223 MBONE, a high bandwidth network on top of the Internet which carries 224 audio and video broadcasts. In order to do that, you would most 225 likely run the program mrouted. If you haven't heard about it, you 226 don't need it. 227 228config IP_MROUTE_MULTIPLE_TABLES 229 bool "IP: multicast policy routing" 230 depends on IP_MROUTE && IP_ADVANCED_ROUTER 231 select FIB_RULES 232 help 233 Normally, a multicast router runs a userspace daemon and decides 234 what to do with a multicast packet based on the source and 235 destination addresses. If you say Y here, the multicast router 236 will also be able to take interfaces and packet marks into 237 account and run multiple instances of userspace daemons 238 simultaneously, each one handling a single table. 239 240 If unsure, say N. 241 242config IP_PIMSM_V1 243 bool "IP: PIM-SM version 1 support" 244 depends on IP_MROUTE 245 help 246 Kernel side support for Sparse Mode PIM (Protocol Independent 247 Multicast) version 1. This multicast routing protocol is used widely 248 because Cisco supports it. You need special software to use it 249 (pimd-v1). Please see <http://netweb.usc.edu/pim/> for more 250 information about PIM. 251 252 Say Y if you want to use PIM-SM v1. Note that you can say N here if 253 you just want to use Dense Mode PIM. 254 255config IP_PIMSM_V2 256 bool "IP: PIM-SM version 2 support" 257 depends on IP_MROUTE 258 help 259 Kernel side support for Sparse Mode PIM version 2. In order to use 260 this, you need an experimental routing daemon supporting it (pimd or 261 gated-5). This routing protocol is not used widely, so say N unless 262 you want to play with it. 263 264config SYN_COOKIES 265 bool "IP: TCP syncookie support" 266 ---help--- 267 Normal TCP/IP networking is open to an attack known as "SYN 268 flooding". This denial-of-service attack prevents legitimate remote 269 users from being able to connect to your computer during an ongoing 270 attack and requires very little work from the attacker, who can 271 operate from anywhere on the Internet. 272 273 SYN cookies provide protection against this type of attack. If you 274 say Y here, the TCP/IP stack will use a cryptographic challenge 275 protocol known as "SYN cookies" to enable legitimate users to 276 continue to connect, even when your machine is under attack. There 277 is no need for the legitimate users to change their TCP/IP software; 278 SYN cookies work transparently to them. For technical information 279 about SYN cookies, check out <http://cr.yp.to/syncookies.html>. 280 281 If you are SYN flooded, the source address reported by the kernel is 282 likely to have been forged by the attacker; it is only reported as 283 an aid in tracing the packets to their actual source and should not 284 be taken as absolute truth. 285 286 SYN cookies may prevent correct error reporting on clients when the 287 server is really overloaded. If this happens frequently better turn 288 them off. 289 290 If you say Y here, you can disable SYN cookies at run time by 291 saying Y to "/proc file system support" and 292 "Sysctl support" below and executing the command 293 294 echo 0 > /proc/sys/net/ipv4/tcp_syncookies 295 296 after the /proc file system has been mounted. 297 298 If unsure, say N. 299 300config NET_IPVTI 301 tristate "Virtual (secure) IP: tunneling" 302 select INET_TUNNEL 303 select NET_IP_TUNNEL 304 depends on INET_XFRM_MODE_TUNNEL 305 ---help--- 306 Tunneling means encapsulating data of one protocol type within 307 another protocol and sending it over a channel that understands the 308 encapsulating protocol. This can be used with xfrm mode tunnel to give 309 the notion of a secure tunnel for IPSEC and then use routing protocol 310 on top. 311 312config NET_UDP_TUNNEL 313 tristate 314 select NET_IP_TUNNEL 315 default n 316 317config NET_FOU 318 tristate "IP: Foo (IP protocols) over UDP" 319 select XFRM 320 select NET_UDP_TUNNEL 321 ---help--- 322 Foo over UDP allows any IP protocol to be directly encapsulated 323 over UDP include tunnels (IPIP, GRE, SIT). By encapsulating in UDP 324 network mechanisms and optimizations for UDP (such as ECMP 325 and RSS) can be leveraged to provide better service. 326 327config NET_FOU_IP_TUNNELS 328 bool "IP: FOU encapsulation of IP tunnels" 329 depends on NET_IPIP || NET_IPGRE || IPV6_SIT 330 select NET_FOU 331 ---help--- 332 Allow configuration of FOU or GUE encapsulation for IP tunnels. 333 When this option is enabled IP tunnels can be configured to use 334 FOU or GUE encapsulation. 335 336config INET_AH 337 tristate "IP: AH transformation" 338 select XFRM_ALGO 339 select CRYPTO 340 select CRYPTO_HMAC 341 select CRYPTO_MD5 342 select CRYPTO_SHA1 343 ---help--- 344 Support for IPsec AH. 345 346 If unsure, say Y. 347 348config INET_ESP 349 tristate "IP: ESP transformation" 350 select XFRM_ALGO 351 select CRYPTO 352 select CRYPTO_AUTHENC 353 select CRYPTO_HMAC 354 select CRYPTO_MD5 355 select CRYPTO_CBC 356 select CRYPTO_SHA1 357 select CRYPTO_DES 358 select CRYPTO_ECHAINIV 359 ---help--- 360 Support for IPsec ESP. 361 362 If unsure, say Y. 363 364config INET_ESP_OFFLOAD 365 tristate "IP: ESP transformation offload" 366 depends on INET_ESP 367 select XFRM_OFFLOAD 368 default n 369 ---help--- 370 Support for ESP transformation offload. This makes sense 371 only if this system really does IPsec and want to do it 372 with high throughput. A typical desktop system does not 373 need it, even if it does IPsec. 374 375 If unsure, say N. 376 377config INET_IPCOMP 378 tristate "IP: IPComp transformation" 379 select INET_XFRM_TUNNEL 380 select XFRM_IPCOMP 381 ---help--- 382 Support for IP Payload Compression Protocol (IPComp) (RFC3173), 383 typically needed for IPsec. 384 385 If unsure, say Y. 386 387config INET_XFRM_TUNNEL 388 tristate 389 select INET_TUNNEL 390 default n 391 392config INET_TUNNEL 393 tristate 394 default n 395 396config INET_XFRM_MODE_TRANSPORT 397 tristate "IP: IPsec transport mode" 398 default y 399 select XFRM 400 ---help--- 401 Support for IPsec transport mode. 402 403 If unsure, say Y. 404 405config INET_XFRM_MODE_TUNNEL 406 tristate "IP: IPsec tunnel mode" 407 default y 408 select XFRM 409 ---help--- 410 Support for IPsec tunnel mode. 411 412 If unsure, say Y. 413 414config INET_XFRM_MODE_BEET 415 tristate "IP: IPsec BEET mode" 416 default y 417 select XFRM 418 ---help--- 419 Support for IPsec BEET mode. 420 421 If unsure, say Y. 422 423config INET_DIAG 424 tristate "INET: socket monitoring interface" 425 default y 426 ---help--- 427 Support for INET (TCP, DCCP, etc) socket monitoring interface used by 428 native Linux tools such as ss. ss is included in iproute2, currently 429 downloadable at: 430 431 http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2 432 433 If unsure, say Y. 434 435config INET_TCP_DIAG 436 depends on INET_DIAG 437 def_tristate INET_DIAG 438 439config INET_UDP_DIAG 440 tristate "UDP: socket monitoring interface" 441 depends on INET_DIAG && (IPV6 || IPV6=n) 442 default n 443 ---help--- 444 Support for UDP socket monitoring interface used by the ss tool. 445 If unsure, say Y. 446 447config INET_RAW_DIAG 448 tristate "RAW: socket monitoring interface" 449 depends on INET_DIAG && (IPV6 || IPV6=n) 450 default n 451 ---help--- 452 Support for RAW socket monitoring interface used by the ss tool. 453 If unsure, say Y. 454 455config INET_DIAG_DESTROY 456 bool "INET: allow privileged process to administratively close sockets" 457 depends on INET_DIAG 458 default n 459 ---help--- 460 Provides a SOCK_DESTROY operation that allows privileged processes 461 (e.g., a connection manager or a network administration tool such as 462 ss) to close sockets opened by other processes. Closing a socket in 463 this way interrupts any blocking read/write/connect operations on 464 the socket and causes future socket calls to behave as if the socket 465 had been disconnected. 466 If unsure, say N. 467 468menuconfig TCP_CONG_ADVANCED 469 bool "TCP: advanced congestion control" 470 ---help--- 471 Support for selection of various TCP congestion control 472 modules. 473 474 Nearly all users can safely say no here, and a safe default 475 selection will be made (CUBIC with new Reno as a fallback). 476 477 If unsure, say N. 478 479if TCP_CONG_ADVANCED 480 481config TCP_CONG_BIC 482 tristate "Binary Increase Congestion (BIC) control" 483 default m 484 ---help--- 485 BIC-TCP is a sender-side only change that ensures a linear RTT 486 fairness under large windows while offering both scalability and 487 bounded TCP-friendliness. The protocol combines two schemes 488 called additive increase and binary search increase. When the 489 congestion window is large, additive increase with a large 490 increment ensures linear RTT fairness as well as good 491 scalability. Under small congestion windows, binary search 492 increase provides TCP friendliness. 493 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/ 494 495config TCP_CONG_CUBIC 496 tristate "CUBIC TCP" 497 default y 498 ---help--- 499 This is version 2.0 of BIC-TCP which uses a cubic growth function 500 among other techniques. 501 See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf 502 503config TCP_CONG_WESTWOOD 504 tristate "TCP Westwood+" 505 default m 506 ---help--- 507 TCP Westwood+ is a sender-side only modification of the TCP Reno 508 protocol stack that optimizes the performance of TCP congestion 509 control. It is based on end-to-end bandwidth estimation to set 510 congestion window and slow start threshold after a congestion 511 episode. Using this estimation, TCP Westwood+ adaptively sets a 512 slow start threshold and a congestion window which takes into 513 account the bandwidth used at the time congestion is experienced. 514 TCP Westwood+ significantly increases fairness wrt TCP Reno in 515 wired networks and throughput over wireless links. 516 517config TCP_CONG_HTCP 518 tristate "H-TCP" 519 default m 520 ---help--- 521 H-TCP is a send-side only modifications of the TCP Reno 522 protocol stack that optimizes the performance of TCP 523 congestion control for high speed network links. It uses a 524 modeswitch to change the alpha and beta parameters of TCP Reno 525 based on network conditions and in a way so as to be fair with 526 other Reno and H-TCP flows. 527 528config TCP_CONG_HSTCP 529 tristate "High Speed TCP" 530 default n 531 ---help--- 532 Sally Floyd's High Speed TCP (RFC 3649) congestion control. 533 A modification to TCP's congestion control mechanism for use 534 with large congestion windows. A table indicates how much to 535 increase the congestion window by when an ACK is received. 536 For more detail see http://www.icir.org/floyd/hstcp.html 537 538config TCP_CONG_HYBLA 539 tristate "TCP-Hybla congestion control algorithm" 540 default n 541 ---help--- 542 TCP-Hybla is a sender-side only change that eliminates penalization of 543 long-RTT, large-bandwidth connections, like when satellite legs are 544 involved, especially when sharing a common bottleneck with normal 545 terrestrial connections. 546 547config TCP_CONG_VEGAS 548 tristate "TCP Vegas" 549 default n 550 ---help--- 551 TCP Vegas is a sender-side only change to TCP that anticipates 552 the onset of congestion by estimating the bandwidth. TCP Vegas 553 adjusts the sending rate by modifying the congestion 554 window. TCP Vegas should provide less packet loss, but it is 555 not as aggressive as TCP Reno. 556 557config TCP_CONG_NV 558 tristate "TCP NV" 559 default n 560 ---help--- 561 TCP NV is a follow up to TCP Vegas. It has been modified to deal with 562 10G networks, measurement noise introduced by LRO, GRO and interrupt 563 coalescence. In addition, it will decrease its cwnd multiplicatively 564 instead of linearly. 565 566 Note that in general congestion avoidance (cwnd decreased when # packets 567 queued grows) cannot coexist with congestion control (cwnd decreased only 568 when there is packet loss) due to fairness issues. One scenario when they 569 can coexist safely is when the CA flows have RTTs << CC flows RTTs. 570 571 For further details see http://www.brakmo.org/networking/tcp-nv/ 572 573config TCP_CONG_SCALABLE 574 tristate "Scalable TCP" 575 default n 576 ---help--- 577 Scalable TCP is a sender-side only change to TCP which uses a 578 MIMD congestion control algorithm which has some nice scaling 579 properties, though is known to have fairness issues. 580 See http://www.deneholme.net/tom/scalable/ 581 582config TCP_CONG_LP 583 tristate "TCP Low Priority" 584 default n 585 ---help--- 586 TCP Low Priority (TCP-LP), a distributed algorithm whose goal is 587 to utilize only the excess network bandwidth as compared to the 588 ``fair share`` of bandwidth as targeted by TCP. 589 See http://www-ece.rice.edu/networks/TCP-LP/ 590 591config TCP_CONG_VENO 592 tristate "TCP Veno" 593 default n 594 ---help--- 595 TCP Veno is a sender-side only enhancement of TCP to obtain better 596 throughput over wireless networks. TCP Veno makes use of state 597 distinguishing to circumvent the difficult judgment of the packet loss 598 type. TCP Veno cuts down less congestion window in response to random 599 loss packets. 600 See <http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=1177186> 601 602config TCP_CONG_YEAH 603 tristate "YeAH TCP" 604 select TCP_CONG_VEGAS 605 default n 606 ---help--- 607 YeAH-TCP is a sender-side high-speed enabled TCP congestion control 608 algorithm, which uses a mixed loss/delay approach to compute the 609 congestion window. It's design goals target high efficiency, 610 internal, RTT and Reno fairness, resilience to link loss while 611 keeping network elements load as low as possible. 612 613 For further details look here: 614 http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf 615 616config TCP_CONG_ILLINOIS 617 tristate "TCP Illinois" 618 default n 619 ---help--- 620 TCP-Illinois is a sender-side modification of TCP Reno for 621 high speed long delay links. It uses round-trip-time to 622 adjust the alpha and beta parameters to achieve a higher average 623 throughput and maintain fairness. 624 625 For further details see: 626 http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html 627 628config TCP_CONG_DCTCP 629 tristate "DataCenter TCP (DCTCP)" 630 default n 631 ---help--- 632 DCTCP leverages Explicit Congestion Notification (ECN) in the network to 633 provide multi-bit feedback to the end hosts. It is designed to provide: 634 635 - High burst tolerance (incast due to partition/aggregate), 636 - Low latency (short flows, queries), 637 - High throughput (continuous data updates, large file transfers) with 638 commodity, shallow-buffered switches. 639 640 All switches in the data center network running DCTCP must support 641 ECN marking and be configured for marking when reaching defined switch 642 buffer thresholds. The default ECN marking threshold heuristic for 643 DCTCP on switches is 20 packets (30KB) at 1Gbps, and 65 packets 644 (~100KB) at 10Gbps, but might need further careful tweaking. 645 646 For further details see: 647 http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf 648 649config TCP_CONG_CDG 650 tristate "CAIA Delay-Gradient (CDG)" 651 default n 652 ---help--- 653 CAIA Delay-Gradient (CDG) is a TCP congestion control that modifies 654 the TCP sender in order to: 655 656 o Use the delay gradient as a congestion signal. 657 o Back off with an average probability that is independent of the RTT. 658 o Coexist with flows that use loss-based congestion control. 659 o Tolerate packet loss unrelated to congestion. 660 661 For further details see: 662 D.A. Hayes and G. Armitage. "Revisiting TCP congestion control using 663 delay gradients." In Networking 2011. Preprint: http://goo.gl/No3vdg 664 665config TCP_CONG_BBR 666 tristate "BBR TCP" 667 default n 668 ---help--- 669 670 BBR (Bottleneck Bandwidth and RTT) TCP congestion control aims to 671 maximize network utilization and minimize queues. It builds an explicit 672 model of the the bottleneck delivery rate and path round-trip 673 propagation delay. It tolerates packet loss and delay unrelated to 674 congestion. It can operate over LAN, WAN, cellular, wifi, or cable 675 modem links. It can coexist with flows that use loss-based congestion 676 control, and can operate with shallow buffers, deep buffers, 677 bufferbloat, policers, or AQM schemes that do not provide a delay 678 signal. It requires the fq ("Fair Queue") pacing packet scheduler. 679 680choice 681 prompt "Default TCP congestion control" 682 default DEFAULT_CUBIC 683 help 684 Select the TCP congestion control that will be used by default 685 for all connections. 686 687 config DEFAULT_BIC 688 bool "Bic" if TCP_CONG_BIC=y 689 690 config DEFAULT_CUBIC 691 bool "Cubic" if TCP_CONG_CUBIC=y 692 693 config DEFAULT_HTCP 694 bool "Htcp" if TCP_CONG_HTCP=y 695 696 config DEFAULT_HYBLA 697 bool "Hybla" if TCP_CONG_HYBLA=y 698 699 config DEFAULT_VEGAS 700 bool "Vegas" if TCP_CONG_VEGAS=y 701 702 config DEFAULT_VENO 703 bool "Veno" if TCP_CONG_VENO=y 704 705 config DEFAULT_WESTWOOD 706 bool "Westwood" if TCP_CONG_WESTWOOD=y 707 708 config DEFAULT_DCTCP 709 bool "DCTCP" if TCP_CONG_DCTCP=y 710 711 config DEFAULT_CDG 712 bool "CDG" if TCP_CONG_CDG=y 713 714 config DEFAULT_BBR 715 bool "BBR" if TCP_CONG_BBR=y 716 717 config DEFAULT_RENO 718 bool "Reno" 719endchoice 720 721endif 722 723config TCP_CONG_CUBIC 724 tristate 725 depends on !TCP_CONG_ADVANCED 726 default y 727 728config DEFAULT_TCP_CONG 729 string 730 default "bic" if DEFAULT_BIC 731 default "cubic" if DEFAULT_CUBIC 732 default "htcp" if DEFAULT_HTCP 733 default "hybla" if DEFAULT_HYBLA 734 default "vegas" if DEFAULT_VEGAS 735 default "westwood" if DEFAULT_WESTWOOD 736 default "veno" if DEFAULT_VENO 737 default "reno" if DEFAULT_RENO 738 default "dctcp" if DEFAULT_DCTCP 739 default "cdg" if DEFAULT_CDG 740 default "bbr" if DEFAULT_BBR 741 default "cubic" 742 743config TCP_MD5SIG 744 bool "TCP: MD5 Signature Option support (RFC2385)" 745 select CRYPTO 746 select CRYPTO_MD5 747 ---help--- 748 RFC2385 specifies a method of giving MD5 protection to TCP sessions. 749 Its main (only?) use is to protect BGP sessions between core routers 750 on the Internet. 751 752 If unsure, say N. 753