Router Compatibility Guide

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Router Compatibility Guide

This guide lists routers and modems that have been tested for compatibility with SIPSTACK VoIP services. Each entry includes a compatibility status, recommendations, and any configuration changes required.

Tip

Whenever possible, choose a router with QoS (Quality of Service) support if your VoIP phones share an internet connection with computers or other devices. Always update your router firmware to the latest version before troubleshooting. If your router is not listed, contact support@sipstack.com with the make and model.

Caution

The single most common cause of VoIP issues is SIP ALG (Application Layer Gateway). Most routers ship with SIP ALG enabled by default. It must be disabled for VoIP to function correctly. See Disabling SIP ALG for guidance.

Understanding SIP ALG

SIP ALG attempts to rewrite SIP packets as they pass through the router. On most consumer and small-business routers, this breaks call setup and causes issues such as one-way audio, calls that drop after 32 seconds, or phones that fail to register. Disable SIP ALG on any router that supports it.

Compatible Devices

These routers work with SIPSTACK VoIP services without requiring changes beyond standard network setup.

Cisco RV180W

Status: Recommended

A business-grade router with Gigabit Ethernet, VPN, and Wireless-N. Regularly deployed with SIPSTACK services and suitable for small to medium business use. Offers four Ethernet ports; add an unmanaged switch if more ports are required.

Linksys E1200

Status: Compatible Suitable for small offices with 2–5 phones.

Linksys E2500

Status: Compatible Suitable for 2–5 phones. Stronger Wi-Fi than the E1200 with Wireless-N.

Linksys E3500

Status: Compatible Suitable for 2–5 phones with strong dual-band Wi-Fi.

Linksys WRVS4400N

Status: Recommended Business-class router with Wireless-N, Gigabit Ethernet, and VPN. Comparable to the Cisco RV series. Suitable for offices that need QoS and wireless in one unit.

Linksys WRT160N

Status: Compatible — 1–2 phones only No QoS support. Appropriate for very small deployments only.

Linksys WRT54G2

Status: Compatible — 1–2 phones Works with 1–2 SIP phones. Known NAT issues with 3 or more phones. Consider DD-WRT firmware for larger deployments if the hardware revision supports it.

Siemens Speedstream

Status: Compatible — 1–3 phones No QoS support. Not recommended for offices with mixed VoIP and computer traffic.

SonicWall

Status: Compatible — with configuration changes Required settings:

• Use firmware v5.8.12 or lower (v5.8.13+ has a bug affecting incoming calls)
• Enable Consistent NAT
• Disable SIP Transformations
• Set MTU correctly for your ISP
• Under Firewall Settings > Edit LAN > WAN Rule > Advanced: set TCP Connection Inactivity Timeout to 60 minutes, UDP Connection Inactivity Timeout to 3600 seconds
• Under Firewall > Access Rules: add allow rules for SIPSTACK’s IP range on any protocol

Devices Compatible with Configuration Changes Required

These routers work with SIPSTACK VoIP after disabling SIP ALG or making other adjustments.

2Wire Routers and Modems

Status: Possibly compatible after changes Disable SIP ALG via the web interface. If SIP ALG cannot be disabled, bridge the device to a compatible router or replace it.

Cisco Routers (General)

Status: Compatible — may require changes The Cisco 837 requires disabling the NAT SIP service via CLI:

no ip nat service sip udp port 5060

Contact SIPSTACK Support to confirm requirements for your specific Cisco model.

Cisco Linksys RV082, RV016, RV042

Status: Compatible — firmware version required Use firmware v4.0.4.02 or earlier. Later versions cause compatibility issues. Set MTU under Setup > Network to 1500 (cable) or 1492 (DSL). The QoS feature on RV series routers is a significant advantage.

D-Link DIR-615 (Hardware Revision B Only)

Status: Compatible after changes Hardware revision B only — other revisions cannot disable SIP ALG and are not compatible. Disable SIP ALG under Firewall > Application Level Gateway (ALG) Configuration in firmware 2.2.4 or higher.

D-Link DIR-625

Status: Possibly compatible after changes Disable SIP ALG through the web interface. Tested with up to 3–4 phones reliably. Not recommended for larger deployments.

D-Link EBR-2310 (Hardware Revision B Only)

Status: Compatible after changes Hardware revision B only. Disable SIP ALG under Firewall > Application Level Gateway (ALG) Configuration in firmware 2.2.4 or higher.

Fortigate / Fortinet

Status: Compatible after changes Disable SIP ALG via CLI:

config system settings
  set sip-helper disable
  set sip-nat-trace disable
end

Reboot the device, then remove the SIP session helper:

config system session-helper
  show
  (find the SIP entry — typically entry 12)
  delete 12
end

Do not apply protection profiles to SIP firewall rules. See Disabling SIP ALG on FortiGate for detailed steps.

Juniper Netscreen

Status: Compatible after changes Navigate to Configuration > Advanced > ALG and uncheck the SIP checkbox.

Motorola Surfboard

Status: Compatible after changes Must be running firmware v3.3 or higher. Must have SIP ALG disabled.

Netgear FVG318

Status: Compatible after changes Disable SIP ALG by logging into the router, selecting Rules from the left menu, and checking Disable SIP ALG. Ensure firmware is current.

Netopia

Status: Possibly compatible after changes SIP Passthrough (SIP ALG) is enabled by default and must be disabled. The setting is not in the web GUI — use Telnet:

configure
set ip sip-passthrough off
save
exit
restart

For the Netopia 4622xlt, use the console menu and run:

ip nat alg sip enable no
save
exit
restart

Not all Netopia models support this change. If yours does not, replace the device.

SMC 3100

Status: Possibly compatible after changes Must be bridged to a compatible router to work with VoIP. The built-in router function is not compatible.

Tomato Firmware Routers

Status: Possibly compatible after changes Some Tomato-based routers limit concurrent SIP registrations to one. Resolve by navigating to Advanced > Conntrack/Netfilter and enabling the SIP option under Tracking/NAT Helpers. Tested on Asus RT-N16 running Tomato.

Zyxel

Status: Possibly compatible after changes Disable SIP ALG via Telnet. Use the arrow keys in the console to navigate to System Maintenance > Command Interpreter Mode and enter:

ip nat service sip active 0

You should receive a confirmation “SIP ALG Disable”. If bridging is possible, bridge to a compatible router instead.

Incompatible Devices

These devices are not compatible with SIPSTACK VoIP services and should be replaced.

Device	Reason
Actiontec GT704WG	Not SIP compatible — drops calls after 20 seconds
Asus RT-N66U	No SIP ALG disable option — not compatible with any SIP phones
Belkin (all models)	Not compatible with VoIP — cannot be used with SIPSTACK service
D-Link DIR-825	Not compatible with VoIP
D-Link WBR-1310	No option to disable SIP ALG
Hitron CGN3 (Rogers)	SIP ALG cannot be disabled — do not place phones in DMZ
Linksys WRT54G / WRT54GX / WRT54GL / WRT54GS	Stock firmware damages SIP packets — try DD-WRT firmware as an alternative
Netgear FVS318	Cannot disable SIP ALG
Netgear WGR614	Cannot disable SIP ALG
Netgear WGT624	Cannot disable SIP ALG
Netgear WRN2000	Cannot disable SIP ALG
SMC Routers (general)	Most SMC models are not compatible — bridge or replace
Thompson TG-585	No method to disable SIP ALG — bridging does not resolve the issue

General VoIP Router Requirements

When selecting a router for a VoIP deployment, look for:

Feature	Why It Matters
SIP ALG disable option	SIP ALG breaks call signaling on most networks
QoS support	Prioritizes voice traffic over data to prevent choppy audio
Configurable UDP session timeout	Prevents registration from dropping on long calls
Sufficient NAT table size	Required for sites with many concurrent calls
Stable firmware with VoIP support	Reduces likelihood of SIP NAT traversal bugs

Supported IP Phone Brands

SIPSTACK-compatible IP phone brands currently supported include:

• Yealink — T-series and W-series
• Grandstream — GRP and GXP series
• Polycom VVX — 300, 400, 500, 600 series
• Cisco SPA — SPA303, SPA504G, SPA514G, SPA525G
• Generic SIP devices (auto-provisioning support varies by model)

Related Resources

• General Firewall Configuration for VoIP
• Disabling SIP ALG on FortiGate Firewalls
• Configure Your ISP Modem to Bridge Mode