#
  # 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

  	  <http://www.savetz.com/mbone/>. Information about the multicast

  	  capabilities of the various network cards is contained in
  	  <file:Documentation/networking/multicast.txt>. 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.txt>.

  	  If unsure, say N here.

  choice

  	prompt "Choose IP: FIB lookup algorithm (choose FIB_HASH if unsure)"
  	depends on IP_ADVANCED_ROUTER

  	default ASK_IP_FIB_HASH

  config ASK_IP_FIB_HASH

  	bool "FIB_HASH"
  	---help---

  	  Current FIB is very proven and good enough for most users.

  
  config IP_FIB_TRIE
  	bool "FIB_TRIE"
  	---help---

  	  Use new experimental LC-trie as FIB lookup algorithm.
  	  This improves lookup performance if you have a large
  	  number of routes.
  
  	  LC-trie is a longest matching prefix lookup algorithm which
  	  performs better than FIB_HASH for large routing tables.
  	  But, it consumes more memory and is more complex.
  
  	  LC-trie is described in:
  
  	  IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
  	  IEEE Journal on Selected Areas in Communications, 17(6):1083-1092,
  	  June 1999
  
  	  An experimental study of compression methods for dynamic tries
  	  Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
  	  http://www.nada.kth.se/~snilsson/public/papers/dyntrie2/

  endchoice

  config IP_FIB_HASH

  	def_bool ASK_IP_FIB_HASH || !IP_ADVANCED_ROUTER

  config IP_FIB_TRIE_STATS
  	bool "FIB TRIE statistics"
  	depends on IP_FIB_TRIE
  	---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 are interested in this, please see the preliminary
  	  documentation at <http://www.compendium.com.ar/policy-routing.txt>
  	  and <ftp://post.tepkom.ru/pub/vol2/Linux/docs/advanced-routing.tex>.
  	  You will need supporting software from
  	  <ftp://ftp.tux.org/pub/net/ip-routing/>.
  
  	  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_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/filesystems/nfs/nfsroot.txt> 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/filesystems/nfs/nfsroot.txt> 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/filesystems/nfs/nfsroot.txt> for details.

  
  # not yet ready..

  #   bool '    IP: ARP support' CONFIG_IP_PNP_ARP

  config NET_IPIP
  	tristate "IP: tunneling"

  	select INET_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
  	tristate "IP: GRE tunnels over IP"

  	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
  	bool "IP: multicast routing"
  	depends on IP_MULTICAST
  	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. Information about the multicast
  	  capabilities of the various network cards is contained in
  	  <file:Documentation/networking/multicast.txt>. 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 ARPD

  	bool "IP: ARP daemon support"

  	---help---

  	  The kernel maintains an internal cache which maps IP addresses to
  	  hardware addresses on the local network, so that Ethernet/Token Ring/
  	  etc. frames are sent to the proper address on the physical networking
  	  layer. Normally, kernel uses the ARP protocol to resolve these
  	  mappings.
  
  	  Saying Y here adds support to have an user space daemon to do this
  	  resolution instead. This is useful for implementing an alternate
  	  address resolution protocol (e.g. NHRP on mGRE tunnels) and also for
  	  testing purposes.
  
  	  If unsure, say N.

  
  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 <http://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 INET_AH
  	tristate "IP: AH transformation"

  	select XFRM
  	select CRYPTO
  	select CRYPTO_HMAC
  	select CRYPTO_MD5
  	select CRYPTO_SHA1
  	---help---
  	  Support for IPsec AH.
  
  	  If unsure, say Y.
  
  config INET_ESP
  	tristate "IP: ESP transformation"

  	select XFRM
  	select CRYPTO

  	select CRYPTO_AUTHENC

  	select CRYPTO_HMAC
  	select CRYPTO_MD5

  	select CRYPTO_CBC

  	select CRYPTO_SHA1
  	select CRYPTO_DES
  	---help---
  	  Support for IPsec ESP.
  
  	  If unsure, say Y.
  
  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_XFRM_MODE_TRANSPORT
  	tristate "IP: IPsec transport mode"
  	default y
  	select XFRM
  	---help---
  	  Support for IPsec transport mode.
  
  	  If unsure, say Y.
  
  config INET_XFRM_MODE_TUNNEL
  	tristate "IP: IPsec tunnel mode"
  	default y
  	select XFRM
  	---help---
  	  Support for IPsec tunnel mode.
  
  	  If unsure, say Y.

  config INET_XFRM_MODE_BEET
  	tristate "IP: IPsec BEET mode"
  	default y
  	select XFRM
  	---help---
  	  Support for IPsec BEET mode.
  
  	  If unsure, say Y.

  config INET_LRO

  	bool "Large Receive Offload (ipv4/tcp)"

  	default y

  	---help---
  	  Support for Large Receive Offload (ipv4/tcp).
  
  	  If unsure, say Y.

  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://linux-net.osdl.org/index.php/Iproute2>.

  	  If unsure, say Y.

  config INET_TCP_DIAG
  	depends on INET_DIAG
  	def_tristate INET_DIAG

  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"

  	depends on EXPERIMENTAL

  	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 http://www.icir.org/floyd/hstcp.html

  config TCP_CONG_HYBLA
  	tristate "TCP-Hybla congestion control algorithm"

  	depends on EXPERIMENTAL

  	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"

  	depends on EXPERIMENTAL

  	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_SCALABLE
  	tristate "Scalable TCP"

  	depends on EXPERIMENTAL

  	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"
  	depends on EXPERIMENTAL
  	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"
  	depends on EXPERIMENTAL
  	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://www.ntu.edu.sg/home5/ZHOU0022/papers/CPFu03a.pdf

  config TCP_CONG_YEAH
  	tristate "YeAH TCP"
  	depends on EXPERIMENTAL

  	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"
  	depends on EXPERIMENTAL
  	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

  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_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 "cubic"

  config TCP_MD5SIG
  	bool "TCP: MD5 Signature Option support (RFC2385) (EXPERIMENTAL)"
  	depends on EXPERIMENTAL
  	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.