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docs:guide-user:network:switch_router_gateway_and_nat [2019/03/25 17:55] – ↷ Links adapted because of a move operation tmomasdocs:guide-user:network:switch_router_gateway_and_nat [2020/12/07 07:05] – [Switch vs Router vs Gateway] update links vgaetera
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-===== Router vs Switch vs Gateway and why NAT influences this decision =====+====== Router vs Switch vs Gateway and why NAT influences this decision ======
  
 The following is meant as roundup The following is meant as roundup
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 ===== Switch vs Router vs Gateway ===== ===== Switch vs Router vs Gateway =====
- 
 Network devices can operate in 3 different modes: Network devices can operate in 3 different modes:
  
-**[[docs:guide-user:network:openwrt_as_clientdevice|OpenWrt as Client Device - Connecting the device to an existing network]]**\\+**[[docs:guide-user:network:openwrt_as_clientdevice|OpenWrt as client device]]**\\
 If you want to connect your device to an existing network to provide additional functions (for example, you just want to use the Wi-Fi network it provides, the additional ethernet ports, or the device is a NAS serving files over the network, or a mini-server offering some other service). If you want to connect your device to an existing network to provide additional functions (for example, you just want to use the Wi-Fi network it provides, the additional ethernet ports, or the device is a NAS serving files over the network, or a mini-server offering some other service).
  
-**[[docs:guide-user:network:lede_as_routerdevice|OpenWrt as router device]]**\\+**[[docs:guide-user:network:openwrt_as_routerdevice|OpenWrt as router device]]**\\
 If you want to run OpenWrt in its default router configuration, where the device routes traffic between several LAN devices connected to the LAN ports and another network on the WAN port (commonly to an "ethernet modem" that is in fact acting as a gateway). If you want to run OpenWrt in its default router configuration, where the device routes traffic between several LAN devices connected to the LAN ports and another network on the WAN port (commonly to an "ethernet modem" that is in fact acting as a gateway).
  
-**as gateway device**\\+**OpenWrt as gateway device**\\
 Your device also behaves as router. But in contrast to the 'as router device' mode, in this mode your device either uses an integrated modem to connect to the Internet or has an external modem attached on its WAN port that needs one of the following protocols for proper operation: WAN interface protocols. Your device also behaves as router. But in contrast to the 'as router device' mode, in this mode your device either uses an integrated modem to connect to the Internet or has an external modem attached on its WAN port that needs one of the following protocols for proper operation: WAN interface protocols.
  
 ===== Router/Gateway and Double NAT problem with IPv4 or mixed IPv4/IPv6  ===== ===== Router/Gateway and Double NAT problem with IPv4 or mixed IPv4/IPv6  =====
- 
 <WRAP center round todo 90%> <WRAP center round todo 90%>
-You are a OpenWrt newcomer? Does this page with lots of technical network information seem scary? Are you worried that you don't know enough to make these decisions now?\\  +Are you an OpenWrt newcomer? Does this page with lots of technical network information seem scary? Are you worried that you don't know enough to make these decisions now?\\  
--> Just stop reading and use the default configuration for now. Your device will act as a router in a cascaded double NAT scenario which will work just fine for normal internet access, so you don't have to do anything. or...\\ +-> Just stop reading and use the default configuration for now. Your device will act as a router in a cascaded double NAT scenario which will work just fine for normal internet access, so you don't have to do anything.\\ 
--> Get familiar with OpenWrt first, come back later and decide+-> Alternatively, [[docs:guide-quick-start:start|get familiar with OpenWrt]] first, then come back later and decide how to proceed.
 </WRAP> </WRAP>
  
-[[docs:guide-user:network:integrating-lede-introduction|Double NAT]] is issue that exists solely with IPv4. In a few decades, when the whole world is fully IPv6 enabled, this won't be a problem anymore, as IPv6 strictly forbids NAT, in the meantime for IPv4, act according to this how-to.+[[docs:guide-user:network:integrating-openwrt-introduction|Double NAT]] is an issue that exists solely with IPv4. In a few decades, when the whole world is fully IPv6 enabled devices, this won't be a problem anymore, as IPv6 strictly forbids NAT. In the meantime for IPv4, act according to this how-to.
  
-Problem of IPv4 is: If you simply add an additional IPv4 router to an existing router of your ISP (internet service provider), you will face a problem called "double NAT": your newly added router does NAT and the existing router also does NAT, resulting in your client data traffic being NATed twicebefore it reaches the internet.+The problem of IPv4 is that if you simply add an additional IPv4 router to an existing router of your ISP (internet service provider), you will face a problem called **double NAT** - both the newly added router and the existing ISP-supplied router do NAT, resulting in your client data traffic being "NATedtwice before it reaches the internet.
  
-This double NAT scenario won't cause problems on basic tasks like browsing the internet or reading mails. +This double NAT scenario won't cause problems for basic tasks like browsing the internet, but it can cause problems when you are trying to host servers at home that you want to be reachable from the internetor when doing peer-to-peer online gaming (which often uses the UDP protocol and does some funny firewall stuff called "UDP hole-punching").
-But it can cause problemswhen you are trying to host servers at home that you want to be reachable from the internet or when doing peer-to-peer online gaming (which often uses UDP protocol and does some funny firewall stuff called "UDP-hole punching")+
  
-To deal with this double NAT problem and use IPv4 as flawlessly as possible, you need to choose between several options, how OpenWrt gets connected on its upstream side +To deal with this double NAT problem and use IPv4 as flawlessly as possible, you need to choose how OpenWrt gets connected on its upstream side from several options. Note that in all these examples, the OpenWrt device is assumed to be on the "inside" of the network, i.e. clients <-> OpenWrt device <-> ISP device <-> Internet. Since the OpenWrt device is our main concern, we'll refer to //upstream// and //downstream// connections relative to it: 
-  * upstream = the connection from the OpenWrt device to your network infrastructure +  * **Upstream**: the connection from the OpenWrt device to your network infrastructure 
-  * downstream = your home client devices connecting to your OpenWrt device+  * **Downstream**: your home client devices connecting to your OpenWrt device
  
-You basically have the following options to connect the upstream side of OpenWrt to your existing home network+There is a range of options to connect the upstream side of OpenWrt to your existing home networkEach option tries to work around the double NAT problem with different technical tricks or configuration
-Each option tries to work around the double NAT problem with different technical tricks or configuration.+ 
 +====== Routers / Gateways ======
  
 ^NAT ^ Usage variant ^ Visualization ^ ^NAT ^ Usage variant ^ Visualization ^
-double | OpenWrt as router acting in default cascaded router double-NAT configuration | clients <-> OpenWrt router with NAT <-> ISP router with NAT <-> Internet | +single | [[#device_as_router_internet_isp_device_as_modem-bridge|OpenWrt as router and having an internet ISP device configured as modem-bridge]] | clients <-> OpenWrt router with NAT <-> ISP bridge (no NAT) <-> Internet | 
-single | OpenWrt as router and having an internet ISP device configured as modem-bridge | clients <-> OpenWrt router with NAT <-> ISP bridge (no NAT<-> Internet | +| single | [[#device_as_router_as_exposed_host_in_the_isp_router|OpenWrt as router, OpenWrt router being "exposed host" in the ISP router]] | clients <-> OpenWrt router with NAT <-> ISP router with NAT + "exposed host" feature <-> Internet | 
-| double | OpenWrt as router in double-NAT configuration with Dualstack Lite on ISP side | clients <-> OpenWrt router with NAT <-> ISP router with DS-Lite NAT <-> Internet | +double | [[#openwrt_as_cascaded_router_behind_another_router_double_nat|OpenWrt as router acting in default cascaded router double-NAT configuration]] | clients <-> OpenWrt router with NAT <-> ISP router with NAT <-> Internet | 
-| single | OpenWrt as router with disabled NAT, additional routing rules in both routers | clients <-> OpenWrt router (no NAT) <-> routing rules <-> ISP router with NAT <-> Internet | +| double | [[#device_as_double-nat_router_with_dual-stack_lite|OpenWrt as router in double-NAT configuration with Dualstack Lite on ISP side]] | clients <-> OpenWrt router with NAT <-> ISP router with DS-Lite NAT <-> Internet | 
-single OpenWrt as router, OpenWrt router being "exposed host" in the ISP router | clients <-> OpenWrt router with NAT <-> ISP router with NAT + "exposed host" feature <-> Internet | +| single | [[#device_as_router_with_disabled_nat_additional_routing_rules|OpenWrt as router with disabled NAT, additional routing rules in both routers]] | clients <-> OpenWrt router (no NAT) <-> routing rules <-> ISP router with NAT <-> Internet | 
-| 0 | look-out: OpenWrt as router in IPv6 only configuration + ISP router | clients <-> OpenWrt router (no NAT) <-> ISP router (no NAT) <-> Internet | +[[#device_as_router_in_an_ideal_ipv6-only_configuration|look-out: OpenWrt as router in IPv6 only configuration + ISP router]] | clients <-> OpenWrt router (no NAT) <-> ISP router (no NAT) <-> Internet | 
-| single | OpenWrt as gateway using either OpenWrt-device-built-in or external modem | clients <-> OpenWrt as gateway with NAT <-> built-in/external modem (no NAT) <-> Internet | +| single | [[#device_as_a_gateway_with_a_true_modem_between_it_and_the_internet|OpenWrt as gateway using either OpenWrt-device-built-in or external modem]] | clients <-> OpenWrt as gateway with NAT <-> built-in/external modem (no NAT) <-> Internet | 
-| single | OpenWrt as switch (connected by wire or access point or as wifi repeater) | clients <-> OpenWrt as switch (no NAT) <-> ISP router (with NAT) <-> Internet |+ 
 +====== Switches and Client APs ====== 
 +| single | Three usage Variants: \\ [[#openwrt_as_wireless_repeater_wifi_wifi_switch|OpenWrt as wireless repeater (wifi <-> wifi switch)]] \\ [[#openwrt_as_wireless_access_point_wifi_wired_switch|OpenWrt as wireless access point (wifi <-> wired switch)]] \\ [[#openwrt_as_a_wire_wire_switch|OpenWrt as wire (wire <-> wire switch)]] | clients <-> OpenWrt as switch (no NAT) <-> ISP router (with NAT) <-> Internet |
   
  
 Note that for all of these upstream connection variants, the following applies: Note that for all of these upstream connection variants, the following applies:
  
-  * all variants allow to handle both wireless and wired clients on your downstream side (=your client devices connected to your local network+  * all variants can handle both wireless and wired clients on the downstream side (i.e. client devices connected to your LAN
-  * all variants allow to host software services for both downstream and upstream side (like NAS shares).+  * all variants can host software services for both downstream and upstream sides (like NAS shares)
  
  
 ==== OpenWrt as cascaded router behind another router (double NAT) ==== ==== OpenWrt as cascaded router behind another router (double NAT) ====
 +This is the default (and easiest) option for your OpenWrt device. For this scenario you simply connect the OpenWrt WAN port to an unused LAN port of your existing ISP router.
 +  * usually the ISP router has its firewall and NAT on, and provides DHCP on the downstream side (which is the upstream side of your OpenWrt)
 +  * OpenWrt also has its firewall and NAT on, and it provides DHCP as well on its downstream (which is the upstream side of your connecting clients)
  
-This is the default (and easiest) option for your OpenWrt deviceright after the OpenWrt installation for off-the-shelf devices sold as "router", that have 1 Ethernet-WAN port and some Ethernet-LAN ports, because for this scenario you simply connect the OpenWrt WAN port to an unused LAN port of your existing ISP router. +So what'the problem? Some traffic scenarios do not work through double NATsuch as hosting servers or playing online games.
-  * usually the ISP router has its firewall on and NAT on and provides DHCP on the downstream side (which is the upstream side of your OpenWrt) +
-  * OpenWrt also has it's firewall on and NAT on and it provides DHCP as well on the downstream (which is the upstream side of your connecting clients)+
  
-So whats the problem? +The problem isn't so much IPv4 NAT, it's a combination of: 
-Some traffic scenarios may not work, line hosting servers for the internet or playing online games. +
- +
-The problem isn't so much IPv4 NAT (=Network address translation), it's a combination of: +
   - NAT usage   - NAT usage
-  - how homerouter firewalls treat UDP-trafficThe firewall treats UDP data traffic statefullThat means if a sourceIP:sourcePort -> targetIP:targetPort package goes out, it will lower the firewall in the reverse direction for a short time, such that the target can answer with the same combination of address and portssourceIP:sourcePort <- targetIP:targetPort.  +  - how firewalls in consumer routers treat UDP traffic.\\The firewall treats UDP traffic as **stateful**This means that if a sourceIP:sourcePort -> targetIP:targetPort package goes out, it will lower the firewall in the reverse direction for a short time, such that the target can answer with the same combination of address and ports (sourceIP:sourcePort <- targetIP:targetPort)
-  - and how mostly online games use tricks to get peer-to-peer data traffic of other players through your firewall(s) to your game client.+  - many online games use tricks to get peer-to-peer data traffic of other players through your firewall(s) to your game client
  
-Unfortunately the firewall details aren't a fully standardized behavior. And unfortunately the NAT behavior that happens in parallel isn't predictable either: Every router may decide little bit differently how it maps addresses and ports on outgoing traffic. +Unfortunately the firewall details aren't a fully standardized behavior. And the NAT behavior that happens in parallel isn't predictable either - every router has slightly different method of deciding how to map addresses to ports on outgoing traffic. Most games and game consoles report this as the "NAT status" of your router, using four broad categories of //open////moderate////strict//and //blocked//, which aren't standardized either - each game vendor may use them for slightly different technical details.
-Most games and game consoles report this as "NAT status" of your router, using 4 different high level categories "open, moderate, strict, blocked", which aren't standardized either - each game vendor may use them for slightly different technical details.+
  
-So should you use this double NAT scenario and be happy with it? +So should you use this double NAT scenario and be happy with it? It highly depends on your equipment and your usage scenario. Double NAT is not automatically bad. 
-It highly depends on your equipment and your usage scenario. Double NAT is not automatically bad. +- if you just do browsing and email, you don't have to care (your internet browsing will not even be slowed down by double NAT)
-- if you just do browsing and mailing, you don't have to care (your internet browsing will not even be slowed down by double NAT).+
 - check if you want to run servers at home that you want to expose to the internet (e.g. a VPN or web server) - such hosting will definitely not work over double NAT  - check if you want to run servers at home that you want to expose to the internet (e.g. a VPN or web server) - such hosting will definitely not work over double NAT 
-- checkif your usual online games work flawlessly.+- check if your usual online games work flawlessly
  
-Now most online games use weird UDP tricks to temporarily bypass your router firewall (without opening your firewall to the whole world), to get less-lagging UDP packets to your game client. Usually those tricks can only bypass a single NATed home router, but not 2 of them. You will find out, if you either cannot connect at all to online sessions or if there is noticeably more game lag than usual (more lag happensbecause most games will first try to fallback from UDP to TCP, before giving up, if the so called "UDP hole punching" through your 2 firewalls/NATs won't work. This TCP-fallback will sometimes be noticeable). Most online games report this as "NAT status" in the game settings. Your aim usually will be to either have this status "open" or "moderate". If your game engine reports anything else, it is usually failing on your firewalls+double NAT and it will then fallback to the slower TCP and can even fail completely to connect to a game session (and I guess you should be able to notice that, if you are left alone in an online game session).+Most online games use weird UDP tricks to temporarily bypass your router firewall (without opening your firewall to the whole world), to get less-laggy UDP packets to your game client. Usually those tricks can only bypass a single NATed home router, not two as in double NAT. You will find out, if you either cannot connect at all to online sessions or if there is noticeably more game lag than usual (more lag happens because most games will first try to fallback from UDP to TCP, before giving up, if the so called "UDP hole punching" through your 2 firewalls/NATs won't work - this TCP-fallback will sometimes be noticeable). Most online games report this as "NAT status" in the game settings. Your aim usually will be to either have this status "open" or "moderate". If your game engine reports anything else, it is usually failing on your two firewalls and double NATand it will then fallback to the slower TCP and can even fail completely to connect to a game session (and you should be able to notice that, if you are left alone in an online game session).
  
-The next few sections explain what you can do to bypass these problems, while keeping both routers and firewalls enabled +The next few sections explain what you can do to bypass these problems, while keeping both routers and firewalls enabledJust keep in mind: don't try to fix problems that you do not have.
-Just keep in mind: Don't try to fix problems that you do not have.+
  
 ==== Device as router, internet ISP device as modem-bridge ==== ==== Device as router, internet ISP device as modem-bridge ====
-Mostly for Cable internet, you can often choose to reconfigure your ISP cable router into 1 of 2 operation modes: +Mostly for cable internet, you can often choose to reconfigure your ISP cable router into either **router mode** or **bridge mode**. Sometimes you have to configure this in nested online portal menus of your ISP (and not on your ISP router web GUI).
-  - router mode +
-  - bridge mode+
  
-Sometimes you have to configure this in in nested online portal menus of your ISP (and not on your ISP router GUI).+When set to bridge mode, the ISP router starts behaving like a pass through device: it will superficially act as a modem and will authenticate you as a legitimate customer, but will otherwise just pass through the IPv4 traffic unchanged to your OpenWrt router. The firewall and NAT and DHCP and all the normal "router" services of the ISP device will simply be disabled when set to bridge mode.
  
-When set to bridge mode, the ISP router starts behaving like a pass through device: it will only authenticate you as a legitimate customerbut will otherwise just passthrough the IPv4 traffic unchanged to your OpenWrt router. The firewall and NAT and DHCP of the ISP device will simply be disabled, when set to bridge mode.+If you require a bridged ISP router, learn how to set it up properly [[docs:guide-user:network:wan:bridge-mode|here]].
  
-[[docs:guide-user:network:wan:bridge-mode|Bridge Mode - how its supposed to be done]]+==== Device as double-NAT router with Dual-Stack Lite ==== 
 +Often you do not have a choice whether your ISP gives you a real IPv4 address or a discredited //dual-stack lite// IPv4 address. If you want to understand Dual-Stack Lite in contrast to regular dual stack, please research the full story on [[https://en.wikipedia.org/wiki/Dual-Stack_Lite|Wikipedia]] or [[https://tools.ietf.org/html/rfc6333|RFC 6333]].
  
-==== Device as double-NAT router with Dualstack Lite ====+Very often Dual-Stack Lite is offered as a default package by cable TVor fiber-based ISPs. A key feature of DS-Lite is that it has so called //carrier-grade NAT// happening in some network equipment several blocks away from your home at your ISP's site, not in your ISP router at home. 
  
-Often you do not have a choicewhether your ISP gives you a real IPv4 address or an often discredited dual stack lite IPv4 address. +It is important to mention that Dual-Stack Lite and this carrier-grade NAT isn't really implemented in a standardized way. It can have slightly different implementation behaviourdepending on the actual equipment that the ISP has bought and how this equipment is configured.
-(please research the full story e.g. on wikipedia, if you want to understand what Dualstack Lite is, in contrast to dual stack)+
  
-Very often dual stack lite is offered as default package by TVcableor fiber-based Internet providers. +Sadly this technique won't help you to expose any home services over IPv4 on the internet this won't be possible with DS-Lite in any caseBut if online gaming over DS-Lite is your only concernyou might want to check if your double NAT on IPv4 is a problem at all in your favorite online games. Nowadays, often the carrier-grade NAT of DS-Lite is configured in a manner very friendly to online gamesresulting in a "moderate" NAT rating in the game engine even when having the additional OpenWrt NAT cascaded in front of it and even when running with default firewall rules.
-A key feature of DS-Lite is, that it has so called carrier-grade NAT happening in some network equipment several blocks away from your home at your ISP's sitenot in your ISP router at home+
  
-Now it is important, to mention that dual stack lite and this carrier-grade NAT isn't really implemented in a standardized way. +So if gaming (and game-related UDP peer-to-peer traffic handling) is your only concern regarding the double-NAT problem, you may just want to check your online games first and their reported NAT status, before investing extensive time in solving a double NAT problem that might not even cause a problem in everyday use.
-It can have slightly different implementation behaviour, depending on the actual equipment that the ISP has bought and depending on how this equipment is configured. +
- +
-Sadly this won't help you, to expose any home services over IPv4 on the internet - This won't be possible with dual stack lite in any case. +
- +
-But if online gaming over DS-Lite is your only concern, you might want to check if your double NAT on IPv4 is at all a problem in your favorite online games. +
-Nowadays, often the carrier grade NAT of DS Lite is configured very online game-friedly, resulting in a "moderate" NAT rating in the game engine even when having the additional OpenWrt NAT cascaded in front of it and even when running with default firewall rules. +
- +
-So if gaming (and game related UDP-peer-to-peer traffic handling) is your only concern regarding the double-NAT problem, you may just want to check your favorite games first and their reported NAT status, before investing extensive time in solving a double NAT problem that maybe does not even cause a problem for you.+
  
 ===== Device as router with disabled NAT, additional routing rules ===== ===== Device as router with disabled NAT, additional routing rules =====
-Using this scenario depends onwhether your ISP router supports custom routing rules. +Using this scenario depends on whether your ISP router supports custom routing rules. This requires that your ISP router allows you to define forward routing rules (often ISP routers are restricted in function and do not allow this).
- +
-This requires that your ISP router allows to define forward routing rules (often ISP routers are functional restricted in function and do not allow this).+
  
-The idea is of this solution is +The idea of this solution is 
-  * to disable NAT on the OpenWrt router, but keep it'routing (and firewall) on. +  * to disable NAT on the OpenWrt router, but keep its routing (and firewall) on 
-  * so both your OpenWrt and the ISP router have routing enabled +  * routing on the ISP router is also enabled 
-  * you have to define non overlapping separate IP ranges and static IP addresses for the OpenWrt router and the ISP router+  * you have to define non-overlapping IP ranges and static IP addresses for the two routers
   * as OpenWrt's NAT is disabled, you need to manually set static routes, such that clients on both routers can send traffic to the other router   * as OpenWrt's NAT is disabled, you need to manually set static routes, such that clients on both routers can send traffic to the other router
-  * you need to add a static routing on the OpenWrt router, forwarding all Internet-address ranges to the ISP router +  * you need to add a static route on the OpenWrt router to forward all Internet-address ranges to the ISP router 
-  * you need to add a static routing on the ISP router, forwarding the address range managed by OpenWrt to the OpenWrt router+  * you need to add a static route on the ISP router to forward the local address range managed by OpenWrt to the OpenWrt router
  
  
 ===== Device as router as "exposed host" in the ISP router ===== ===== Device as router as "exposed host" in the ISP router =====
 +Only some ISP routers have this feature, sometimes called a //DMZ// (demilitarized zone), //DMZ for single server//, //exposed host//, //IP passthrough//, or //poor man's bridge mode// (there is no standardized name). This feature enables your ISP router to define a single one of its downstream clients to be a so called "exposed host". The ISP router will then forward all incoming Internet traffic from its upstream side to this "exposed host".
  
-This is an optional feature of your ISP router (so it could be that your ISP router may not support this). +This effectively disables NAT on the ISP router only for a single connected device on the ISP router downstream side: for obvious reasonswe will be connecting our OpenWrt router as this exposed host. So in the end, we have achieved single NAT solely in the network chain towards the OpenWrt router.
-Sometimes this feature is called "DMZ for single server""exposed host" or "poor man bridge mode" (there is no standardized name) +
  
-The feature enables your ISP router to define a single one of its downstream ports to be a so called "exposed host"+Remember you still need to define the usual port forwarding rules in your OpenWrt router if you want to expose OpenWrt-connected servers to the Internet, since we haven't set up an exposed host on the internal network.
-The ISP router will then forward all incoming Internet traffic from its upstream side to this "exposed host"+
- +
-This effectively disables NAT on the ISP router only for a single connected device on the ISP router downstream side: For obvious reasons, we will be connecting our OpenWrt router as this exposed host. So in the end, we have achieved single NAT solely in the network chain towards the OpenWrt router. +
- +
-(Remeber you still need to define usual port forwarding rules in your OpenWrt routerif you want to expose OpenWrt-connected-servers to the Internet)+
  
 Drawbacks of this method are: Drawbacks of this method are:
 - the feature may not be supported by your ISP router, you'll have to find out if it does - the feature may not be supported by your ISP router, you'll have to find out if it does
-- the OpenWrt upstream port is exposed to the Internet, so be sure that you have not added any non-needed careless extra rules to the default OpenWrt firewall rule set +- the OpenWrt upstream port is exposed to the Internet, so be sure that you have not added any careless or extraneous rules to the ruleset 
-- one of your ISP router ports is now without firewall protection. So be careful with this one downstream ISP router port now, in case you ever connect something else to this port. +- one of your ISP router ports is now without firewall protection, so be careful with this one downstream ISP router port in case you ever connect something else to it
- +
-[[docs:guide-user:network:wan:dmz-based-bridge-mode|"Exposed host" a.k.a "Poor Man's Bridge Mode"]] +
- +
-===== Device as router in an ideal IPv6 only configuration ===== +
-Obviously this ideal world does not yet exist. Its just a look-out for much later.\\ +
-Once this happens, the previous chapters of this howto can be ignored\\ +
-This will then be the default (and easiest) and only router option required for your IPv6 OpenWrt device, as you it will just work out of the box for all business cases.\\ +
-There will be no NAT issues, there is no longer a discussion whether to switch the ISP router to bridged or routed and no more discussion whether a "exposed host" config is needed. +
- +
-  * You will be choosing to run OpenWrt as router (without variants), if you want to have an extra firewall active inside your home network (in addition to the firewall of your ISP router) +
-  * You will be choosing to run OpenWrt as switch instead (see below), if you don't want the extra bit of routing and firewall inside your home network +
-  * You will be choosing to run OpenWrt as gateway instead (also see below), if you need to connect to Internet via a special modem protocol+
  
 +Learn how to set up a "poor man's bridge" [[docs:guide-user:network:wan:dmz-based-bridge-mode|here]].
  
 +===== Device as router in an ideal IPv6-only configuration =====
 +Obviously this ideal world does not yet exist, it's just a prospect for much later. Once this happens, the previous chapters of this page can be ignored. This will then be the default and only router option required for your IPv6 OpenWrt device, as you it will just work out of the box for all business cases. There will be no NAT issues, there is no longer a discussion whether to switch the ISP router to bridged or routed, and no more discussion whether an "exposed host" configuration is needed. You will be able to choose three ways of running OpenWrt:
 +  * as a router (without variants), if you want to have an extra firewall active inside your home network (in addition to the firewall of your ISP router)
 +  * as a switch instead (see below), if you don't want the extra bit of routing and firewall inside your home network
 +  * as a gateway instead (see below), if you need to connect to Internet via a special modem protocol
  
 ===== Device as a gateway, with a true modem between it and the Internet ===== ===== Device as a gateway, with a true modem between it and the Internet =====
-If your OpenWrt device has no WAN port at all out of the box adn has a built-in modem with something like a VDSL-phone port, or if it has a WAN port and you have an external modem that can be put in "bridge mode" (either full bridge or half bridge), this is for you.+If your OpenWrt device has no WAN port at all out of the box and has a built-in modem with something like a VDSL-phone port, or if it has a WAN port and you have an external modem that can be put in "bridge mode" (either full bridge or half bridge), this is for you.
  
-See [[docs:guide-user:network:wan:internet.connection|this tutorial]]+See [[docs:guide-user:network:wan:internet.connection|this tutorial]].
  
  
-===== OpenWrt as wireless repeater (wifi<->wifi switch) =====+===== OpenWrt as wireless repeater (wifiwifi switch) =====
 If your OpenWrt device does not have LAN ports or if you don't want to connect any other devices using RJ45 LAN cables, then most probably you want to use the OpenWrt device as a WiFi repeater in your existing network. If your OpenWrt device does not have LAN ports or if you don't want to connect any other devices using RJ45 LAN cables, then most probably you want to use the OpenWrt device as a WiFi repeater in your existing network.
  
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   * Note that OpenWrt will no longer listen on the typical default router address of your subnet (e.g. ip-address 192.168.1.1), but will get a custom address (either by DHCP from your other router or you have manually set a static address of the subnet of the other wifi)   * Note that OpenWrt will no longer listen on the typical default router address of your subnet (e.g. ip-address 192.168.1.1), but will get a custom address (either by DHCP from your other router or you have manually set a static address of the subnet of the other wifi)
      
-[[docs:guide-user:network:wifi:relay_configuration|Wifi Extender or Repeater or Bridge Configuration]] +For more information, refer to [[docs:guide-user:network:wifi:relay_configuration|Wifi Extender or Repeater or Bridge Configuration]].
  
-Note: In case you are interested in creating a so called "wireless mesh" instead of a wireless repeater, you will have to refer to other projects like libremesh.org at this time.+Note: In case you are interested in creating a so called "wireless mesh" instead of a wireless repeater, you will have to refer to other projects, e.g. [[http://libremesh.org]] or [[https://open-mesh.org]] at this time.
  
  
-===== OpenWrt as wireless access point (wifi<->wire switch)=====+===== OpenWrt as wireless access point (wifi↔wired switch)=====
 As a wireless access point, OpenWrt connects to the existing network by wire. OpenWrt then acts as a networking device that allows your Wi-Fi devices to connect to the wired network over OpenWrt.  As a wireless access point, OpenWrt connects to the existing network by wire. OpenWrt then acts as a networking device that allows your Wi-Fi devices to connect to the wired network over OpenWrt. 
   * the wired network provides Internet access   * the wired network provides Internet access
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-===== OpenWrt as a wire-to-wire switch =====+===== OpenWrt as a wirewire switch =====
 This scenario has already been covered in the previous described access point scenario, as the downstream LAN ports in OpenWrt are active by default, providing switching: All your wired and wireless clients connected to either OpenWrt or your other network switches can talk to each other without restrictions, as no firewall is active on the OpenWrt device. This scenario has already been covered in the previous described access point scenario, as the downstream LAN ports in OpenWrt are active by default, providing switching: All your wired and wireless clients connected to either OpenWrt or your other network switches can talk to each other without restrictions, as no firewall is active on the OpenWrt device.
   * so just follow the wireless access point description - just with the difference: if you only need a wire-to-wire-switch, then just do not enable the downstream wifi   * so just follow the wireless access point description - just with the difference: if you only need a wire-to-wire-switch, then just do not enable the downstream wifi
  • Last modified: 2021/01/13 18:33
  • by bobmichael