Guest WiFi + abuse control for beginners

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-'''''Wiki Path''''': [[Main_Page|DD-WRT Wiki Main]] / [[Tutorials]] / [[Guest_Network]] / '''Guest WiFi + abuse control for beginners'''+{{Languages|Guest WiFi + abuse control for beginners}}
-*Also see [[Multiple_WLANs|Multiple WLANs]]+
-----+
-__TOC__+
-== Introduction ==+Note: This page must be reevaluated. Please, someone with better expertise should verify that the main dhcp server still works correctly after adding the insulated wlan dhcpd server. Had to hard-reset my router.. main lan/wlan was not assigning any dhcp leases anymore, yet second wlan (guest) had internet working perfectly and good dhcp server. no chance to telnet/ssh... locked out... admin interface not reachable from guest network. Thank you.
-This tutorial for beginners provides the basics of creating and controlling a "guest" Wi-Fi Virtual Access Point (VAP) that allows guest users access to the public Internet while keeping them out of your private network.+
-The following procedures assume the basic setup of the router has been completed and Wi-Fi access to your network is functioning. You should also have determined that the router is capable of simultaneously supporting multiple SSIDs. For a method of checking the revision number of your router's chip and thus its multiple-SSID capability, see https://www.howtogeek.com/153827/how-to-enable-a-guest-access-point-on-your-wireless-network/.<!-- The last sentence in this paragraph should be a footnote, but this ancient version of MediaWiki doesn't support the <ref></ref> and <references /> tags. --> 
-Before proceeding, make sure your router has a working reset button and you have backed up the router's configuration, so if you should get stuck, you can reset it and restore the configuration. (See the '''Administration >> Backup''' tab in the DD-WRT Control Panel.)+This tutorial is for beginners, and therefore before proceeding make sure you have working reset button
 +and have backed up you configuration (so you can reset your router and restore configuration if you stuck somewhere). This guide will show you the basics of creating and controlling Guest WiFi. Also see [[Guest Network]] for more details and methods.
-== Instructions == 
[[Image:Guest_VAP.PNG|thumbnail|Creating Guest VAP]] [[Image:Guest_VAP.PNG|thumbnail|Creating Guest VAP]]
-In the '''Wireless >> Basic Settings''' tab of the DD-WRT Control Panel, click "Add" in the "Virtual Interfaces" section. A new Virtual Interface is created, with a title like+[[Image:DHCPd.PNG|thumbnail|Adding DHCP for Guests]]
-::<font color="blue">'''Virtual Interfaces wl0.1 SSID [dd-wrt_vap] HWAddr [22:AA:4B:36:EC:10]'''</font>+[[Image:Interface_limiting.PNG|thumbnail|Hardcoded limiting interfaces]]
-Note the string after "Virtual Interfaces" ("wl0.1" in this example from a Linksys router using a Broadcom chip), as it will help you identify the correct section of later Control Panel pages in which settings will be applied.+[[Image:max_bulk.PNG|thumbnail|Setting priorities]]
 +[[Image:OpenDNS1.png|thumbnail|Abuse controlling]]
 +[[Image:OpenDNS2.png|thumbnail|Web content filtering]]
 +[[Image:404.png|thumbnail|Content blocked]]
-Change the Wireless Network Name (SSID) from the default "dd-wrt_vap" to how you want it to appear to guest users when they connect to your network, ''e.g.'', "MyNetwork_guest". 
-Set '''AP isolation''' to "Enable" so that guest users cannot see each other. AP Isolation drops all traffic between clients connected to the VAP. This is recommended to prevent wireless snooping attacks via the guest Wi-Fi.+For that purpose we will first create VAP (Virtual Access Point) for guests.
-''Click on the Save button at the bottom of the page''. If you do not click the Save button, settings you just made will be lost as you switch from one tab to another.+On '''Wireless''' -> '''Basic Setup''' tab click Add on Virtual Interfaces section.
 +'''Enable AP isolation''' so that guests can not see each others. AP Isolation drops all traffic between clients connected to the VAP.
 +If you want secure Guest WiFI its recommended to enable this feature to help mitigate Wi-Fi snooping attacks.
-Go to the '''Wireless >> Wireless Security''' tab to set the security type and wireless network password. Although the VAP can function with no encryption and password, it can lead to abuse and is thus not recommended. ''Click on the Save button at the bottom of the page''.+Set '''Network Configuration''' to ''Unbridged'', '''Enable NAT''' (so that guest can have internet), enable '''Net isolation''' (this option creates a couple of firewall rules that blocks guest to reach your private network). Net isolation works ONLY on unbridged interface on newer builds starting from: Broadcom 23020, Atheros 24759, and Ralink (Mediatek) 25934.
- +*AP Isolation = Guests can not hack each other on guest VAP
-Set '''Network Configuration''' to '''Unbridged''', '''Enable NAT''' (gives guests Internet access), and '''enable Net isolation''' (creates firewall rules blocking guests from the private network).+*Net isolation = Guests can not hack your private LAN/WLAN
-Net isolation works ''only'' on an unbridged interface on newer builds, ''starting from build'':+
-*Broadcom (23020), Atheros (24759), MediaTek/Ralink (25934)<br />AP Isolation = Guests cannot see each other on guest VAP<br />Net isolation = Guests cannot see your private LAN+WLAN +
'''Enable Forced DNS Redirection''' and enter the OpenDNS server IP (208.67.222.222) in the Optional DNS target field. This will prevent users from using their own DNS servers (and hence get around content filtering) '''Enable Forced DNS Redirection''' and enter the OpenDNS server IP (208.67.222.222) in the Optional DNS target field. This will prevent users from using their own DNS servers (and hence get around content filtering)
by intercepting DNS queries and forcing them to use the DNS servers you specify. by intercepting DNS queries and forcing them to use the DNS servers you specify.
-Enter the IP Address and Subnet Mask, ''e.g.'', 172.16.1.1 / 255.255.255.0. (Private networks use IP addresses in the range 172.16.1.1 to 172.16.1.255.) Click the "Save" button, then click the "Apply" button at the bottom of the page. Wait approximately 30 seconds for the new interface (''e.g.'', wl0.1) to be created.+Enter the IP Address and Subnet Mask of yours newly created interface (ath0.1) 172.16.1.1./255.255.255.0
 +Click Save and Apply. Wait about 30 sec. for interface ath0.1 to be created.
 +Note: You still wont be able to connect to this Guest VAP. You must enable DHCP for the clients.
-Although this VAP will now show up in a scan of available Wi-Fi access points using your wireless device, you will not yet be able to connect to it. You must enable DHCP for the clients.+Next step is to '''enable DHCPd''' for the guest wifi. Go to '''Setup''' -> '''Networking''' and on DHCPd section add another dhcp server for the guest network (click add then choose ath0.1 from drop down menu). Select starting IP for guests, max number of IPs and leasetime. Again click Save and Apply. Wait about 30 sec. and try to connect to Guest WiFi. You should be able to browse Internet and shouldn't be able to reach your private network or see other clients on network discovery.
-[[Image:DHCPd.PNG|thumbnail|Adding DHCP for Guests]]+====Bandwidth Limiting====
-Next step is to '''enable DHCPd''' for the guest Wi-Fi. +You can put your private network on Maximum and Guest to bulk. The bulk class is only allocated remaining bandwidth when the remaining classes are idle. If the pipe is full of traffic from other classes, Bulk will only be allocated 1% of total set limit. So, basically your guests will not affect your private speed. Or you can set hardcoded limits with manual entering.
-Go to '''Setup >> Networking''', in the ''DHCPd'' section add a DHCP server for the new guest network (''Add'' then choose the VLAN (e.g., ath0.1) from drop down menu. Select starting and max number of IP address, plus lease time. Click ''Save'' then ''Apply''. Wait about 30sec and try to connect to Guest Wi-Fi. If not working, power cycle the router. You should be able to browse the Internet, but not reach your private network nor see other clients on network discovery.+
-'''Note:''' For a newer method that uses DNSMasq instead of DHCPd, see [[Guest Network#DNSMasq_method|Guest Network § DNSMasq method]].+With '''interface limiting''' both bridged & unbridged, offers ability to rate or priority limit services or ports/port ranges. This can be exceptionally useful to control bandwidth hogs, regulate hotspots, etc. with an interface limit, a guest user can change their ip address & mac address as much as they want trying to get around qos, abusive users can't bypass ur rules without switching off the interface. Examples:
 + vlan1 512/512 0 ssl manual
 +*This means all traffic on vlan1 interface (lan ports for some routers, others use eth) is not limited or shaped, and can reach global limits, except ssl traffic being limited to 512kbps both up & down (64KB/s).
-== Quality of Service (QoS) ==+Multiple entries are possible:
-[[Image:Interface_limiting.PNG|thumbnail|Hardcoded limiting interfaces]]+
-[[Image:max_bulk.PNG|thumbnail|Setting priorities]]+
-'''Bandwidth limiting''' puts the private network on "Maximum" and guest network to "Bulk". The Bulk class is only allocated the remaining bandwidth when other classes are idle. If the pipe is full of traffic from other classes, Bulk will only be allocated 1% of total set limit. This is so your guests will not affect your private network speed. Alternatively, you can manually set hard-coded limits. +
- +
-'''Interface limiting''', both bridged and unbridged, offers ability to rate-limit or priority-limit services or port(s) ranges. This can be exceptionally useful to control bandwidth hogs, regulate hotspots, etc. with an interface limit, preventing guest users from circumventing QoS limits by changing IP and/or MAC addresses. Abusive users can't bypass your rules without switching off the interface. +
- +
-Example:+
- vlan1 512/512 0 ssl manual +
-This means all traffic on the vlan1 interface (lan ports for some routers, others use eth) is not limited nor shaped, and goes "up to" global limits, except SSL traffic, being limited to 512&nbsp;kbps (64&nbsp;kB/s) both up and down. Multiple entries are also possible, for example:+
ath0 512/512 0 ssl manual ath0 512/512 0 ssl manual
ath0 2048/512 0 http manual ath0 2048/512 0 http manual
ath0 512/512 0 ftp manual ath0 512/512 0 ftp manual
-The same applies to what was said above, just for the ath0 wireless interface and only the listed services are rate-limited. Priority limits can also be used, but simultaneous rate limiting and prioritizing on the same service is not supported.+*This is as above except for the ath0 wireless interface, and only the listed services are rate limited. You can instead do priority limits, but rate limiting & prioritizing the same service simultaneously is not supported.
-== Access Restrictions ==+Use [[Access Restrictions]] to block torrents and some VPNs. Determined user is very hard to block because nowdays you have free SSTP VPN services etc. On cheap routers you can not run Proxy, Squid etc so this is all we have...
-[[Access Restrictions]] can be used to block torrents and some VPNs. A determined user is very hard to block, because now there are free SSTP VPN services, etc. On cheap routers you cannot run Proxy, Squid, etc., so to accomplish network abuse filtering we use '''OpenDNS'''.+
- +
-== OpenDNS ==+
-[[Image:OpenDNS1.png|thumbnail|Abuse control]]+
-[[Image:OpenDNS2.png|thumbnail|Web content filtering]]+
-[[Image:404.png|thumbnail|Content blocked]]+
-OpenDNS is a free DNS (Domain Name Server) service to make Internet browsing safer and allegedly faster. By using the OpenDNS DNS server instead of the ISP's DNS server, you are automatically protected from their list of phishing Web sites. However, in order to restrict certain content, ''e.g.'', "adult" sites, you will need to create a free account, register your IP address, and select the categories you want restricted&nbsp;— sexuality, nudity, pornography, lingerie, grotesque, etc. Since most of us have DHCP assigned WAN IP addresses that change periodically, we need to instruct our router to tell OpenDNS the new IP address when it changes. See the [[OpenDNS#OpenDns with DNS-O-Matic for users with a Dynamic IP|DNS-O-Matic]] section of the OpenDNS article. Reboot router, clear browser cache, and manually set public DNS server in your PC NIC adapter to try to avoid restrictions.<br clear="all" />+
-== References and notes ==+====OpenDNS====
-<references /><!-- If this "<references /> tag is visible, it means the MediaWiki software used by this site is at least 15 years out-of-date. -->+OpenDNS can be used for net abuse filtering. It is a free DNS (Domain Name Server) service which makes internet browsing safer and allegedly faster. By simply using their DNS servers instead of your ISP's you are automatically protected from their list of Phishing websites. However, in order to restrict a variety of adult website content you will need to create a free account with them, register your IP address and select the categories you want restricted (i.e. sexuality, nude, pornography, lingerie, grotesque, etc...). Since most of us have DHCP assigned WAN IP addresses that change periodically we need to instruct our router to tell OpenDNS what our new IP address is when it changes. See [https://www.dd-wrt.com/wiki/index.php/OpenDNS#section2/ DNS-O-MATIC]
-[[Category:Wlan]]+Reboot router, clear browser cache, and manually set public dns server in your PC NIC adapter to try to avoid restrictions...
-[[Category:Basic tutorials]]+

Current revision


Note: This page must be reevaluated. Please, someone with better expertise should verify that the main dhcp server still works correctly after adding the insulated wlan dhcpd server. Had to hard-reset my router.. main lan/wlan was not assigning any dhcp leases anymore, yet second wlan (guest) had internet working perfectly and good dhcp server. no chance to telnet/ssh... locked out... admin interface not reachable from guest network. Thank you.


This tutorial is for beginners, and therefore before proceeding make sure you have working reset button and have backed up you configuration (so you can reset your router and restore configuration if you stuck somewhere). This guide will show you the basics of creating and controlling Guest WiFi. Also see Guest Network for more details and methods.

Creating Guest VAP
Creating Guest VAP
Adding DHCP for Guests
Adding DHCP for Guests
Hardcoded limiting interfaces
Hardcoded limiting interfaces
Setting priorities
Setting priorities
Abuse controlling
Abuse controlling
Web content filtering
Web content filtering
Content blocked
Content blocked


For that purpose we will first create VAP (Virtual Access Point) for guests.

On Wireless -> Basic Setup tab click Add on Virtual Interfaces section. Enable AP isolation so that guests can not see each others. AP Isolation drops all traffic between clients connected to the VAP. If you want secure Guest WiFI its recommended to enable this feature to help mitigate Wi-Fi snooping attacks.

Set Network Configuration to Unbridged, Enable NAT (so that guest can have internet), enable Net isolation (this option creates a couple of firewall rules that blocks guest to reach your private network). Net isolation works ONLY on unbridged interface on newer builds starting from: Broadcom 23020, Atheros 24759, and Ralink (Mediatek) 25934.

  • AP Isolation = Guests can not hack each other on guest VAP
  • Net isolation = Guests can not hack your private LAN/WLAN

Enable Forced DNS Redirection and enter the OpenDNS server IP (208.67.222.222) in the Optional DNS target field. This will prevent users from using their own DNS servers (and hence get around content filtering) by intercepting DNS queries and forcing them to use the DNS servers you specify. Enter the IP Address and Subnet Mask of yours newly created interface (ath0.1) 172.16.1.1./255.255.255.0 Click Save and Apply. Wait about 30 sec. for interface ath0.1 to be created. Note: You still wont be able to connect to this Guest VAP. You must enable DHCP for the clients.

Next step is to enable DHCPd for the guest wifi. Go to Setup -> Networking and on DHCPd section add another dhcp server for the guest network (click add then choose ath0.1 from drop down menu). Select starting IP for guests, max number of IPs and leasetime. Again click Save and Apply. Wait about 30 sec. and try to connect to Guest WiFi. You should be able to browse Internet and shouldn't be able to reach your private network or see other clients on network discovery.

[edit] Bandwidth Limiting

You can put your private network on Maximum and Guest to bulk. The bulk class is only allocated remaining bandwidth when the remaining classes are idle. If the pipe is full of traffic from other classes, Bulk will only be allocated 1% of total set limit. So, basically your guests will not affect your private speed. Or you can set hardcoded limits with manual entering.

With interface limiting both bridged & unbridged, offers ability to rate or priority limit services or ports/port ranges. This can be exceptionally useful to control bandwidth hogs, regulate hotspots, etc. with an interface limit, a guest user can change their ip address & mac address as much as they want trying to get around qos, abusive users can't bypass ur rules without switching off the interface. Examples:

vlan1 512/512 0 ssl manual 
  • This means all traffic on vlan1 interface (lan ports for some routers, others use eth) is not limited or shaped, and can reach global limits, except ssl traffic being limited to 512kbps both up & down (64KB/s).

Multiple entries are possible:

ath0 512/512 0 ssl manual 
ath0 2048/512 0 http manual 
ath0 512/512 0 ftp manual 
  • This is as above except for the ath0 wireless interface, and only the listed services are rate limited. You can instead do priority limits, but rate limiting & prioritizing the same service simultaneously is not supported.

Use Access Restrictions to block torrents and some VPNs. Determined user is very hard to block because nowdays you have free SSTP VPN services etc. On cheap routers you can not run Proxy, Squid etc so this is all we have...

[edit] OpenDNS

OpenDNS can be used for net abuse filtering. It is a free DNS (Domain Name Server) service which makes internet browsing safer and allegedly faster. By simply using their DNS servers instead of your ISP's you are automatically protected from their list of Phishing websites. However, in order to restrict a variety of adult website content you will need to create a free account with them, register your IP address and select the categories you want restricted (i.e. sexuality, nude, pornography, lingerie, grotesque, etc...). Since most of us have DHCP assigned WAN IP addresses that change periodically we need to instruct our router to tell OpenDNS what our new IP address is when it changes. See DNS-O-MATIC

Reboot router, clear browser cache, and manually set public dns server in your PC NIC adapter to try to avoid restrictions...