SIP-ALG is a setting that is found inside the administrative menu of most routers.  According to 8x8, this setting must be disabled as 8x8's software already has SIP-ALG built into it's code and leaving it enabled can interfere with call quality.


In order to change the settings in your router, you will need to log into the router itself and change the settings through your internet browser.  Each router is different so please refer to your router's manual on how exactly to log in and change settings. You will also need to know the admin username and password for your router.  


Simply put, this process involves typing the IP address of your gateway (aka your router) into Chrome.  For example, I would type in "192.168.1.1" into the address bar of my browser and then I would see the login screen for my router.


In order to find the router's IP, go to the taskbar search at the bottom of screen and type in "cmd".  Then click open to launch Command Prompt.




Once opened, type in the word "ipconfig" (no quotation marks) and hit the Enter key.



A bunch of text on the screen will pop up.  Look for the words "Default Gateway" and that number next to it is your IP address's router!  It usually starts with "192.168" but other numbers are possible.


Type that number into the browser's address bar and it should take you to a log in screen.  Again, you will need to know the admin username and password in order to log into your router to change settings.



Once inside, look for SIP-ALG inside the menu.  Here is a list of various brands with instructions on how to find SIP-ALG:

Model

How to Disable SIP ALG

Adtran
  • Use the following command: no ip firewall alg sip

Arris Gateway
  • Locate ‘Options’ under ‘Advance’ and uncheck the SIP box.
  • Apply the following credentials: 
    • UN: admin
    • Password: motorola

ASA
  • Locate ‘Class inspection_default’ under ‘Policy-map global_policy’.
  • Use the following command: no inspect sip

Asus
  • Locate ‘WAN/ NAT Passthrough’ under ‘Advanced Settings’
  • Disable ‘Passthrough’.

AVM Fritz!Box

  • No option to disable SIP ALG.

Billion

  • Locate the SIP ALG feature under NAT or router firewall settings.

BT

  • Disable SIP ALG option is only available on BT Business Hub versions 3 and higher.

Cisco (non-ASA)
  • Locate SIP Fixup
  • On General Routers, apply the following: 
    • no ip nat service sip tcp port 5060
    • no ip nat service sip udp port 5060
  • On Enterprise-Class Routers, apply the following: 
    • no ip nat service sip tcp port 5060
    • no ip nat service sip udp port 5060
  • On Pix Devices, apply the following: 
    • no fixup protocol sip 5060
    • no fixup protocol sip udp 5060

D-Link
  • Locate ‘Application Level Gateway (ALG) Configuration’ under ‘Advanced  settings’
  • Uncheck the ‘SIP’ option.

DrayTek
  • For Vigor2760 devices use the ALG feature located under Network/NAT.
  • For other devices use a Telnet client.
  • On Windows systems: 
    • Find the Windows Start button.
    • Search for cmd: hit enter.
    • Type in telnet 192.168.1.1: hit enter.

(Note: Unless you have the Windows telnet client installed, you will need to do that now by locating the Telnet Client in the Windows Programs and Features, and turning it on.)

  • Type in the username and the password in the credentials prompt.
  • Apply the following commands: 
    • sys sip_alg 0
    • sys commit
  • For Draytek Vigor2750 and Vigor2130 devices apply the following commands: 
    • kmodule_ctl nf_nat_sip disable
    • kmodule_ctl nf_conntrack_sip disable

Fortinet
  • Use the following commands from the CLI interface: 
    • config system session-helper
    • show system session-helper
  • Find the SIP session instance, typically indicated by #12
  • Delete #12 or the appropriate number
  • Confirm deletion by re-running ‘show system session-helper’.

Huawei

  • Locate SIP ALG in the Security menu.

Linksys
  • Go to the ‘Advanced’ section on the Admin page and disable the SIP ALG feature. This instruction can be used as a general Linksys router guidance.  
  • For Linksys BEFSR41 routers, go to ‘Port Triggering’ under ‘Applications and Gaming’ on the Admin page. 
    • Type in ‘TCP’ as the application.
    • Type in ‘5060’ into the Start Port and End Port for the ‘Triggering Range’ and ‘Forwarded Range’ fields.
    • Tick ‘Enable’.
    • Save and Reboot.

Mikrotik

  • Disable SIP Helper.

Netgear
  • Locate the advanced settings under Security/Firewall from the admin interface.
  • Disable SIP ALG.
  • Locate Session Limit under Security/Firewall.
  • Increase the UDP timeout to 300 sec.

      

SonicWall
  • Under the VoIP tab:
  • Check ‘Enable Consistent NAT’
  • Uncheck ‘Enable SIP Transformations’.

Speedtouch

  • Check in the user manual for a specific model to see if you need to use Telnet commands to disable SIP ALG.

TP-Link
  • Use the Telnet client by typing cmd in the Windows Start menu.
  • Apply the following command: ip nat service sip sw off

UBEE Gateways
  • Go to ‘Options’ under ‘Advanced’.
  • Uncheck the SIP option.
  • Uncheck the RTSP option.
  • Click Apply.

Virgin SuperHub
  • SIP ALG cannot be disabled.

ZyXEL ZyWALL USG
  • Go to ALG, located under Network/Configuration/Settings.
  • Disable SIP ALG.