| # | |
| # 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/>. 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. | |
| 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 | |
| <http://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/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. | |
| 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 <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 NET_IPVTI | |
| tristate "Virtual (secure) IP: tunneling" | |
| select INET_TUNNEL | |
| select NET_IP_TUNNEL | |
| depends on INET_XFRM_MODE_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 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_ALGO | |
| 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_ALGO | |
| select CRYPTO | |
| select CRYPTO_AUTHENC | |
| select CRYPTO_HMAC | |
| select CRYPTO_MD5 | |
| select CRYPTO_CBC | |
| select CRYPTO_SHA1 | |
| select CRYPTO_DES | |
| select CRYPTO_ECHAINIV | |
| ---help--- | |
| Support for IPsec ESP. | |
| 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_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_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 http://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 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. |