# SPDX-License-Identifier: GPL-2.0-only

  #
  # IP configuration
  #
  config IP_MULTICAST
  	bool "IP: multicasting"

  	help
  	  This is code for addressing several networked computers at once,
  	  enlarging your kernel by about 2 KB. You need multicasting if you
  	  intend to participate in the MBONE, a high bandwidth network on top
  	  of the Internet which carries audio and video broadcasts. More
  	  information about the MBONE is on the WWW at

  	  <https://www.savetz.com/mbone/>. For most people, it's safe to say N.

  
  config IP_ADVANCED_ROUTER
  	bool "IP: advanced router"

  	help

  	  If you intend to run your Linux box mostly as a router, i.e. as a
  	  computer that forwards and redistributes network packets, say Y; you
  	  will then be presented with several options that allow more precise
  	  control about the routing process.
  
  	  The answer to this question won't directly affect the kernel:
  	  answering N will just cause the configurator to skip all the
  	  questions about advanced routing.
  
  	  Note that your box can only act as a router if you enable IP
  	  forwarding in your kernel; you can do that by saying Y to "/proc
  	  file system support" and "Sysctl support" below and executing the
  	  line
  
  	  echo "1" > /proc/sys/net/ipv4/ip_forward
  
  	  at boot time after the /proc file system has been mounted.

  	  If you turn on IP forwarding, you should consider the rp_filter, which

  	  automatically rejects incoming packets if the routing table entry
  	  for their source address doesn't match the network interface they're
  	  arriving on. This has security advantages because it prevents the
  	  so-called IP spoofing, however it can pose problems if you use
  	  asymmetric routing (packets from you to a host take a different path
  	  than packets from that host to you) or if you operate a non-routing
  	  host which has several IP addresses on different interfaces. To turn

  	  rp_filter on use:

  	  echo 1 > /proc/sys/net/ipv4/conf/<device>/rp_filter

  	   or

  	  echo 1 > /proc/sys/net/ipv4/conf/all/rp_filter

  	  Note that some distributions enable it in startup scripts.

  	  For details about rp_filter strict and loose mode read

  	  <file:Documentation/networking/ip-sysctl.rst>.

  	  If unsure, say N here.

  config IP_FIB_TRIE_STATS
  	bool "FIB TRIE statistics"

  	depends on IP_ADVANCED_ROUTER

  	help

  	  Keep track of statistics on structure of FIB TRIE table.
  	  Useful for testing and measuring TRIE performance.

  config IP_MULTIPLE_TABLES
  	bool "IP: policy routing"
  	depends on IP_ADVANCED_ROUTER

  	select FIB_RULES

  	help

  	  Normally, a router decides what to do with a received packet based
  	  solely on the packet's final destination address. If you say Y here,
  	  the Linux router will also be able to take the packet's source
  	  address into account. Furthermore, the TOS (Type-Of-Service) field
  	  of the packet can be used for routing decisions as well.

  	  If you need more information, see the Linux Advanced
  	  Routing and Traffic Control documentation at

  	  <https://lartc.org/howto/lartc.rpdb.html>

  
  	  If unsure, say N.

  config IP_ROUTE_MULTIPATH
  	bool "IP: equal cost multipath"
  	depends on IP_ADVANCED_ROUTER
  	help
  	  Normally, the routing tables specify a single action to be taken in
  	  a deterministic manner for a given packet. If you say Y here
  	  however, it becomes possible to attach several actions to a packet
  	  pattern, in effect specifying several alternative paths to travel
  	  for those packets. The router considers all these paths to be of
  	  equal "cost" and chooses one of them in a non-deterministic fashion
  	  if a matching packet arrives.

  config IP_ROUTE_VERBOSE
  	bool "IP: verbose route monitoring"
  	depends on IP_ADVANCED_ROUTER
  	help
  	  If you say Y here, which is recommended, then the kernel will print
  	  verbose messages regarding the routing, for example warnings about
  	  received packets which look strange and could be evidence of an
  	  attack or a misconfigured system somewhere. The information is
  	  handled by the klogd daemon which is responsible for kernel messages
  	  ("man klogd").

  config IP_ROUTE_CLASSID
  	bool

  config IP_PNP
  	bool "IP: kernel level autoconfiguration"

  	help
  	  This enables automatic configuration of IP addresses of devices and
  	  of the routing table during kernel boot, based on either information
  	  supplied on the kernel command line or by BOOTP or RARP protocols.
  	  You need to say Y only for diskless machines requiring network
  	  access to boot (in which case you want to say Y to "Root file system
  	  on NFS" as well), because all other machines configure the network
  	  in their startup scripts.
  
  config IP_PNP_DHCP
  	bool "IP: DHCP support"
  	depends on IP_PNP

  	help

  	  If you want your Linux box to mount its whole root file system (the
  	  one containing the directory /) from some other computer over the
  	  net via NFS and you want the IP address of your computer to be
  	  discovered automatically at boot time using the DHCP protocol (a
  	  special protocol designed for doing this job), say Y here. In case
  	  the boot ROM of your network card was designed for booting Linux and
  	  does DHCP itself, providing all necessary information on the kernel
  	  command line, you can say N here.
  
  	  If unsure, say Y. Note that if you want to use DHCP, a DHCP server
  	  must be operating on your network.  Read

  	  <file:Documentation/admin-guide/nfs/nfsroot.rst> for details.

  
  config IP_PNP_BOOTP
  	bool "IP: BOOTP support"
  	depends on IP_PNP

  	help

  	  If you want your Linux box to mount its whole root file system (the
  	  one containing the directory /) from some other computer over the
  	  net via NFS and you want the IP address of your computer to be
  	  discovered automatically at boot time using the BOOTP protocol (a
  	  special protocol designed for doing this job), say Y here. In case
  	  the boot ROM of your network card was designed for booting Linux and
  	  does BOOTP itself, providing all necessary information on the kernel
  	  command line, you can say N here. If unsure, say Y. Note that if you
  	  want to use BOOTP, a BOOTP server must be operating on your network.

  	  Read <file:Documentation/admin-guide/nfs/nfsroot.rst> for details.

  
  config IP_PNP_RARP
  	bool "IP: RARP support"
  	depends on IP_PNP
  	help
  	  If you want your Linux box to mount its whole root file system (the
  	  one containing the directory /) from some other computer over the
  	  net via NFS and you want the IP address of your computer to be
  	  discovered automatically at boot time using the RARP protocol (an
  	  older protocol which is being obsoleted by BOOTP and DHCP), say Y
  	  here. Note that if you want to use RARP, a RARP server must be

  	  operating on your network. Read

  	  <file:Documentation/admin-guide/nfs/nfsroot.rst> for details.

  config NET_IPIP
  	tristate "IP: tunneling"

  	select INET_TUNNEL

  	select NET_IP_TUNNEL

  	help

  	  Tunneling means encapsulating data of one protocol type within
  	  another protocol and sending it over a channel that understands the
  	  encapsulating protocol. This particular tunneling driver implements
  	  encapsulation of IP within IP, which sounds kind of pointless, but
  	  can be useful if you want to make your (or some other) machine
  	  appear on a different network than it physically is, or to use
  	  mobile-IP facilities (allowing laptops to seamlessly move between
  	  networks without changing their IP addresses).
  
  	  Saying Y to this option will produce two modules ( = code which can
  	  be inserted in and removed from the running kernel whenever you
  	  want). Most people won't need this and can say N.

  config NET_IPGRE_DEMUX
  	tristate "IP: GRE demultiplexer"
  	help

  	  This is helper module to demultiplex GRE packets on GRE version field criteria.
  	  Required by ip_gre and pptp modules.

  config NET_IP_TUNNEL
  	tristate

  	select DST_CACHE

  	select GRO_CELLS

  	default n

  config NET_IPGRE
  	tristate "IP: GRE tunnels over IP"

  	depends on (IPV6 || IPV6=n) && NET_IPGRE_DEMUX

  	select NET_IP_TUNNEL

  	help
  	  Tunneling means encapsulating data of one protocol type within
  	  another protocol and sending it over a channel that understands the
  	  encapsulating protocol. This particular tunneling driver implements
  	  GRE (Generic Routing Encapsulation) and at this time allows
  	  encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure.
  	  This driver is useful if the other endpoint is a Cisco router: Cisco
  	  likes GRE much better than the other Linux tunneling driver ("IP
  	  tunneling" above). In addition, GRE allows multicast redistribution
  	  through the tunnel.
  
  config NET_IPGRE_BROADCAST
  	bool "IP: broadcast GRE over IP"
  	depends on IP_MULTICAST && NET_IPGRE
  	help
  	  One application of GRE/IP is to construct a broadcast WAN (Wide Area
  	  Network), which looks like a normal Ethernet LAN (Local Area
  	  Network), but can be distributed all over the Internet. If you want
  	  to do that, say Y here and to "IP multicast routing" below.

  config IP_MROUTE_COMMON
  	bool
  	depends on IP_MROUTE || IPV6_MROUTE

  config IP_MROUTE
  	bool "IP: multicast routing"
  	depends on IP_MULTICAST

  	select IP_MROUTE_COMMON

  	help
  	  This is used if you want your machine to act as a router for IP
  	  packets that have several destination addresses. It is needed on the
  	  MBONE, a high bandwidth network on top of the Internet which carries
  	  audio and video broadcasts. In order to do that, you would most

  	  likely run the program mrouted. If you haven't heard about it, you
  	  don't need it.

  config IP_MROUTE_MULTIPLE_TABLES
  	bool "IP: multicast policy routing"

  	depends on IP_MROUTE && IP_ADVANCED_ROUTER

  	select FIB_RULES
  	help
  	  Normally, a multicast router runs a userspace daemon and decides
  	  what to do with a multicast packet based on the source and
  	  destination addresses. If you say Y here, the multicast router
  	  will also be able to take interfaces and packet marks into
  	  account and run multiple instances of userspace daemons
  	  simultaneously, each one handling a single table.
  
  	  If unsure, say N.

  config IP_PIMSM_V1
  	bool "IP: PIM-SM version 1 support"
  	depends on IP_MROUTE
  	help
  	  Kernel side support for Sparse Mode PIM (Protocol Independent
  	  Multicast) version 1. This multicast routing protocol is used widely
  	  because Cisco supports it. You need special software to use it
  	  (pimd-v1). Please see <http://netweb.usc.edu/pim/> for more
  	  information about PIM.
  
  	  Say Y if you want to use PIM-SM v1. Note that you can say N here if
  	  you just want to use Dense Mode PIM.
  
  config IP_PIMSM_V2
  	bool "IP: PIM-SM version 2 support"
  	depends on IP_MROUTE
  	help
  	  Kernel side support for Sparse Mode PIM version 2. In order to use
  	  this, you need an experimental routing daemon supporting it (pimd or
  	  gated-5). This routing protocol is not used widely, so say N unless
  	  you want to play with it.

  config SYN_COOKIES

  	bool "IP: TCP syncookie support"

  	help

  	  Normal TCP/IP networking is open to an attack known as "SYN
  	  flooding". This denial-of-service attack prevents legitimate remote
  	  users from being able to connect to your computer during an ongoing
  	  attack and requires very little work from the attacker, who can
  	  operate from anywhere on the Internet.
  
  	  SYN cookies provide protection against this type of attack. If you
  	  say Y here, the TCP/IP stack will use a cryptographic challenge
  	  protocol known as "SYN cookies" to enable legitimate users to
  	  continue to connect, even when your machine is under attack. There
  	  is no need for the legitimate users to change their TCP/IP software;
  	  SYN cookies work transparently to them. For technical information

  	  about SYN cookies, check out <https://cr.yp.to/syncookies.html>.

  
  	  If you are SYN flooded, the source address reported by the kernel is
  	  likely to have been forged by the attacker; it is only reported as
  	  an aid in tracing the packets to their actual source and should not
  	  be taken as absolute truth.
  
  	  SYN cookies may prevent correct error reporting on clients when the
  	  server is really overloaded. If this happens frequently better turn
  	  them off.

  	  If you say Y here, you can disable SYN cookies at run time by
  	  saying Y to "/proc file system support" and

  	  "Sysctl support" below and executing the command

  	  echo 0 > /proc/sys/net/ipv4/tcp_syncookies

  	  after the /proc file system has been mounted.

  
  	  If unsure, say N.

  config NET_IPVTI
  	tristate "Virtual (secure) IP: tunneling"

  	depends on IPV6 || IPV6=n

  	select INET_TUNNEL

  	select NET_IP_TUNNEL

  	select XFRM

  	help

  	  Tunneling means encapsulating data of one protocol type within
  	  another protocol and sending it over a channel that understands the
  	  encapsulating protocol. This can be used with xfrm mode tunnel to give
  	  the notion of a secure tunnel for IPSEC and then use routing protocol
  	  on top.

  config NET_UDP_TUNNEL
  	tristate

  	select NET_IP_TUNNEL

  	default n

  config NET_FOU
  	tristate "IP: Foo (IP protocols) over UDP"
  	select XFRM
  	select NET_UDP_TUNNEL

  	help

  	  Foo over UDP allows any IP protocol to be directly encapsulated
  	  over UDP include tunnels (IPIP, GRE, SIT). By encapsulating in UDP
  	  network mechanisms and optimizations for UDP (such as ECMP
  	  and RSS) can be leveraged to provide better service.

  config NET_FOU_IP_TUNNELS
  	bool "IP: FOU encapsulation of IP tunnels"
  	depends on NET_IPIP || NET_IPGRE || IPV6_SIT
  	select NET_FOU

  	help

  	  Allow configuration of FOU or GUE encapsulation for IP tunnels.
  	  When this option is enabled IP tunnels can be configured to use
  	  FOU or GUE encapsulation.

  config INET_AH
  	tristate "IP: AH transformation"

  	select XFRM_AH

  	help

  	  Support for IPsec AH (Authentication Header).
  
  	  AH can be used with various authentication algorithms.  Besides
  	  enabling AH support itself, this option enables the generic
  	  implementations of the algorithms that RFC 8221 lists as MUST be
  	  implemented.  If you need any other algorithms, you'll need to enable
  	  them in the crypto API.  You should also enable accelerated
  	  implementations of any needed algorithms when available.

  
  	  If unsure, say Y.
  
  config INET_ESP
  	tristate "IP: ESP transformation"

  	select XFRM_ESP

  	help

  	  Support for IPsec ESP (Encapsulating Security Payload).
  
  	  ESP can be used with various encryption and authentication algorithms.
  	  Besides enabling ESP support itself, this option enables the generic
  	  implementations of the algorithms that RFC 8221 lists as MUST be
  	  implemented.  If you need any other algorithms, you'll need to enable
  	  them in the crypto API.  You should also enable accelerated
  	  implementations of any needed algorithms when available.

  
  	  If unsure, say Y.

  config INET_ESP_OFFLOAD
  	tristate "IP: ESP transformation offload"
  	depends on INET_ESP
  	select XFRM_OFFLOAD
  	default n

  	help

  	  Support for ESP transformation offload. This makes sense
  	  only if this system really does IPsec and want to do it
  	  with high throughput. A typical desktop system does not
  	  need it, even if it does IPsec.
  
  	  If unsure, say N.

  config INET_ESPINTCP
  	bool "IP: ESP in TCP encapsulation (RFC 8229)"
  	depends on XFRM && INET_ESP
  	select STREAM_PARSER
  	select NET_SOCK_MSG

  	select XFRM_ESPINTCP

  	help
  	  Support for RFC 8229 encapsulation of ESP and IKE over
  	  TCP/IPv4 sockets.
  
  	  If unsure, say N.

  config INET_IPCOMP
  	tristate "IP: IPComp transformation"

  	select INET_XFRM_TUNNEL

  	select XFRM_IPCOMP

  	help

  	  Support for IP Payload Compression Protocol (IPComp) (RFC3173),
  	  typically needed for IPsec.

  	  If unsure, say Y.

  config INET_XFRM_TUNNEL
  	tristate
  	select INET_TUNNEL
  	default n

  config INET_TUNNEL

  	tristate
  	default n

  config INET_DIAG
  	tristate "INET: socket monitoring interface"

  	default y

  	help

  	  Support for INET (TCP, DCCP, etc) socket monitoring interface used by
  	  native Linux tools such as ss. ss is included in iproute2, currently

  	  downloadable at:

  	    http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2

  	  If unsure, say Y.

  config INET_TCP_DIAG
  	depends on INET_DIAG
  	def_tristate INET_DIAG

  config INET_UDP_DIAG

  	tristate "UDP: socket monitoring interface"

  	depends on INET_DIAG && (IPV6 || IPV6=n)

  	default n

  	help

  	  Support for UDP socket monitoring interface used by the ss tool.
  	  If unsure, say Y.

  config INET_RAW_DIAG
  	tristate "RAW: socket monitoring interface"
  	depends on INET_DIAG && (IPV6 || IPV6=n)
  	default n

  	help

  	  Support for RAW socket monitoring interface used by the ss tool.
  	  If unsure, say Y.

  config INET_DIAG_DESTROY
  	bool "INET: allow privileged process to administratively close sockets"
  	depends on INET_DIAG
  	default n

  	help

  	  Provides a SOCK_DESTROY operation that allows privileged processes
  	  (e.g., a connection manager or a network administration tool such as
  	  ss) to close sockets opened by other processes. Closing a socket in
  	  this way interrupts any blocking read/write/connect operations on
  	  the socket and causes future socket calls to behave as if the socket
  	  had been disconnected.
  	  If unsure, say N.

  menuconfig TCP_CONG_ADVANCED

  	bool "TCP: advanced congestion control"

  	help

  	  Support for selection of various TCP congestion control
  	  modules.
  
  	  Nearly all users can safely say no here, and a safe default

  	  selection will be made (CUBIC with new Reno as a fallback).

  
  	  If unsure, say N.

  if TCP_CONG_ADVANCED

  
  config TCP_CONG_BIC
  	tristate "Binary Increase Congestion (BIC) control"

  	default m

  	help

  	  BIC-TCP is a sender-side only change that ensures a linear RTT
  	  fairness under large windows while offering both scalability and
  	  bounded TCP-friendliness. The protocol combines two schemes
  	  called additive increase and binary search increase. When the
  	  congestion window is large, additive increase with a large
  	  increment ensures linear RTT fairness as well as good
  	  scalability. Under small congestion windows, binary search
  	  increase provides TCP friendliness.
  	  See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/

  config TCP_CONG_CUBIC
  	tristate "CUBIC TCP"

  	default y

  	help

  	  This is version 2.0 of BIC-TCP which uses a cubic growth function
  	  among other techniques.
  	  See http://www.csc.ncsu.edu/faculty/rhee/export/bitcp/cubic-paper.pdf

  config TCP_CONG_WESTWOOD
  	tristate "TCP Westwood+"

  	default m

  	help

  	  TCP Westwood+ is a sender-side only modification of the TCP Reno
  	  protocol stack that optimizes the performance of TCP congestion
  	  control. It is based on end-to-end bandwidth estimation to set
  	  congestion window and slow start threshold after a congestion
  	  episode. Using this estimation, TCP Westwood+ adaptively sets a
  	  slow start threshold and a congestion window which takes into
  	  account the bandwidth used  at the time congestion is experienced.
  	  TCP Westwood+ significantly increases fairness wrt TCP Reno in
  	  wired networks and throughput over wireless links.

  config TCP_CONG_HTCP

  	tristate "H-TCP"
  	default m

  	help

  	  H-TCP is a send-side only modifications of the TCP Reno
  	  protocol stack that optimizes the performance of TCP
  	  congestion control for high speed network links. It uses a
  	  modeswitch to change the alpha and beta parameters of TCP Reno
  	  based on network conditions and in a way so as to be fair with
  	  other Reno and H-TCP flows.

  config TCP_CONG_HSTCP
  	tristate "High Speed TCP"

  	default n

  	help

  	  Sally Floyd's High Speed TCP (RFC 3649) congestion control.
  	  A modification to TCP's congestion control mechanism for use
  	  with large congestion windows. A table indicates how much to
  	  increase the congestion window by when an ACK is received.

  	  For more detail see https://www.icir.org/floyd/hstcp.html

  config TCP_CONG_HYBLA
  	tristate "TCP-Hybla congestion control algorithm"

  	default n

  	help

  	  TCP-Hybla is a sender-side only change that eliminates penalization of
  	  long-RTT, large-bandwidth connections, like when satellite legs are
  	  involved, especially when sharing a common bottleneck with normal
  	  terrestrial connections.

  config TCP_CONG_VEGAS
  	tristate "TCP Vegas"

  	default n

  	help

  	  TCP Vegas is a sender-side only change to TCP that anticipates
  	  the onset of congestion by estimating the bandwidth. TCP Vegas
  	  adjusts the sending rate by modifying the congestion
  	  window. TCP Vegas should provide less packet loss, but it is
  	  not as aggressive as TCP Reno.

  config TCP_CONG_NV

  	tristate "TCP NV"
  	default n

  	help

  	  TCP NV is a follow up to TCP Vegas. It has been modified to deal with
  	  10G networks, measurement noise introduced by LRO, GRO and interrupt
  	  coalescence. In addition, it will decrease its cwnd multiplicatively
  	  instead of linearly.

  	  Note that in general congestion avoidance (cwnd decreased when # packets
  	  queued grows) cannot coexist with congestion control (cwnd decreased only
  	  when there is packet loss) due to fairness issues. One scenario when they
  	  can coexist safely is when the CA flows have RTTs << CC flows RTTs.

  	  For further details see http://www.brakmo.org/networking/tcp-nv/

  config TCP_CONG_SCALABLE
  	tristate "Scalable TCP"

  	default n

  	help

  	  Scalable TCP is a sender-side only change to TCP which uses a
  	  MIMD congestion control algorithm which has some nice scaling
  	  properties, though is known to have fairness issues.
  	  See http://www.deneholme.net/tom/scalable/

  config TCP_CONG_LP
  	tristate "TCP Low Priority"

  	default n

  	help

  	  TCP Low Priority (TCP-LP), a distributed algorithm whose goal is
  	  to utilize only the excess network bandwidth as compared to the
  	  ``fair share`` of bandwidth as targeted by TCP.
  	  See http://www-ece.rice.edu/networks/TCP-LP/

  config TCP_CONG_VENO
  	tristate "TCP Veno"

  	default n

  	help

  	  TCP Veno is a sender-side only enhancement of TCP to obtain better
  	  throughput over wireless networks. TCP Veno makes use of state
  	  distinguishing to circumvent the difficult judgment of the packet loss
  	  type. TCP Veno cuts down less congestion window in response to random
  	  loss packets.
  	  See <http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=1177186>

  config TCP_CONG_YEAH
  	tristate "YeAH TCP"

  	select TCP_CONG_VEGAS

  	default n

  	help

  	  YeAH-TCP is a sender-side high-speed enabled TCP congestion control
  	  algorithm, which uses a mixed loss/delay approach to compute the
  	  congestion window. It's design goals target high efficiency,
  	  internal, RTT and Reno fairness, resilience to link loss while
  	  keeping network elements load as low as possible.

  	  For further details look here:
  	    http://wil.cs.caltech.edu/pfldnet2007/paper/YeAH_TCP.pdf

  config TCP_CONG_ILLINOIS
  	tristate "TCP Illinois"

  	default n

  	help

  	  TCP-Illinois is a sender-side modification of TCP Reno for
  	  high speed long delay links. It uses round-trip-time to
  	  adjust the alpha and beta parameters to achieve a higher average
  	  throughput and maintain fairness.

  	  For further details see:
  	    http://www.ews.uiuc.edu/~shaoliu/tcpillinois/index.html

  config TCP_CONG_DCTCP
  	tristate "DataCenter TCP (DCTCP)"
  	default n

  	help

  	  DCTCP leverages Explicit Congestion Notification (ECN) in the network to
  	  provide multi-bit feedback to the end hosts. It is designed to provide:

  	  - High burst tolerance (incast due to partition/aggregate),
  	  - Low latency (short flows, queries),
  	  - High throughput (continuous data updates, large file transfers) with
  	    commodity, shallow-buffered switches.

  	  All switches in the data center network running DCTCP must support
  	  ECN marking and be configured for marking when reaching defined switch
  	  buffer thresholds. The default ECN marking threshold heuristic for
  	  DCTCP on switches is 20 packets (30KB) at 1Gbps, and 65 packets
  	  (~100KB) at 10Gbps, but might need further careful tweaking.

  	  For further details see:
  	    http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf

  config TCP_CONG_CDG
  	tristate "CAIA Delay-Gradient (CDG)"
  	default n

  	help

  	  CAIA Delay-Gradient (CDG) is a TCP congestion control that modifies
  	  the TCP sender in order to:

  
  	  o Use the delay gradient as a congestion signal.
  	  o Back off with an average probability that is independent of the RTT.
  	  o Coexist with flows that use loss-based congestion control.
  	  o Tolerate packet loss unrelated to congestion.

  	  For further details see:
  	    D.A. Hayes and G. Armitage. "Revisiting TCP congestion control using
  	    delay gradients." In Networking 2011. Preprint: http://goo.gl/No3vdg

  config TCP_CONG_BBR
  	tristate "BBR TCP"
  	default n

  	help

  	  BBR (Bottleneck Bandwidth and RTT) TCP congestion control aims to
  	  maximize network utilization and minimize queues. It builds an explicit

  	  model of the bottleneck delivery rate and path round-trip propagation
  	  delay. It tolerates packet loss and delay unrelated to congestion. It
  	  can operate over LAN, WAN, cellular, wifi, or cable modem links. It can
  	  coexist with flows that use loss-based congestion control, and can
  	  operate with shallow buffers, deep buffers, bufferbloat, policers, or
  	  AQM schemes that do not provide a delay signal. It requires the fq
  	  ("Fair Queue") pacing packet scheduler.

  choice
  	prompt "Default TCP congestion control"

  	default DEFAULT_CUBIC

  	help
  	  Select the TCP congestion control that will be used by default
  	  for all connections.
  
  	config DEFAULT_BIC
  		bool "Bic" if TCP_CONG_BIC=y
  
  	config DEFAULT_CUBIC
  		bool "Cubic" if TCP_CONG_CUBIC=y
  
  	config DEFAULT_HTCP
  		bool "Htcp" if TCP_CONG_HTCP=y

  	config DEFAULT_HYBLA
  		bool "Hybla" if TCP_CONG_HYBLA=y

  	config DEFAULT_VEGAS
  		bool "Vegas" if TCP_CONG_VEGAS=y

  	config DEFAULT_VENO
  		bool "Veno" if TCP_CONG_VENO=y

  	config DEFAULT_WESTWOOD
  		bool "Westwood" if TCP_CONG_WESTWOOD=y

  	config DEFAULT_DCTCP
  		bool "DCTCP" if TCP_CONG_DCTCP=y

  	config DEFAULT_CDG
  		bool "CDG" if TCP_CONG_CDG=y

  	config DEFAULT_BBR
  		bool "BBR" if TCP_CONG_BBR=y

  	config DEFAULT_RENO
  		bool "Reno"

  endchoice
  
  endif

  config TCP_CONG_CUBIC

  	tristate

  	depends on !TCP_CONG_ADVANCED
  	default y

  config DEFAULT_TCP_CONG
  	string
  	default "bic" if DEFAULT_BIC
  	default "cubic" if DEFAULT_CUBIC
  	default "htcp" if DEFAULT_HTCP

  	default "hybla" if DEFAULT_HYBLA

  	default "vegas" if DEFAULT_VEGAS
  	default "westwood" if DEFAULT_WESTWOOD

  	default "veno" if DEFAULT_VENO

  	default "reno" if DEFAULT_RENO

  	default "dctcp" if DEFAULT_DCTCP

  	default "cdg" if DEFAULT_CDG

  	default "bbr" if DEFAULT_BBR

  	default "cubic"

  config TCP_MD5SIG

  	bool "TCP: MD5 Signature Option support (RFC2385)"

  	select CRYPTO
  	select CRYPTO_MD5

  	help

  	  RFC2385 specifies a method of giving MD5 protection to TCP sessions.

  	  Its main (only?) use is to protect BGP sessions between core routers
  	  on the Internet.
  
  	  If unsure, say N.