A: If you are using VOIP Adapters (ATA) or hardware IP Phones to make low cost high quality Voice over IP calls worldwidely through broadband Home/Office internet connection, but recently your ISP (internet service provider) blocked your VOIP calls, our service is the BEST for you.

In a simple world, our VPN4SIP service will help you to get a secure VPN connection through your existing ISP so you can make VOIP calls without being blocked forever.

A: First, make sure you are using some kind of SIP Adapters(ATA) or standalone hardware based IP phones, and also you are using a some kind of VOIP call service from Internet Telephony Service Providers(ITSP), check our "Home" page for the example list.

Second, you need get a VPN4SIP made VPN Router in order to use our VPN service, this is the ONLY router that works with our service. Any models over the market can't work with our VPN4SIP service. Once you purchase this router plus minimum one month service period subscription,  we will send you detail account information and how to use this plug-n-play router wirth your VOIP devices.


A: No. VPN4SIP.COM is a pure VPN connection service provider for residential VOIP users, we don't provide A-Z call service. Our client MUST have their own VOIP carrier to make international VOIP calls.

A: No. VPN4SIP.COM is a pure VPN connection service provider for residential VOIP users, we don't carry any VOIP hardware devices for sale. Our client MUST get the standalone hardware VOIP Adaptors or IP Phones from their VOIP service providers, or purchased from local channels.

A: VPN4SIP service provides dedicated 100Kbit/s upload bandwidth and 100Kbit/s download bandwidth for each VPN4SIP account.

Because of the VPN tunneling adds additional bytes to the IP payload, so customer's ISP connection need to have 150Kbit/s to 180Kbit/s speed for both upload and download direction in order to get full VPN connection speed from VPN4SIP service.

However if customer only have one VOIP Adaptor and make only one simultaneous call, then 29Kbit/s ISP upload speed and 29Kbit/s ISP download speed is enough (when using G.723.1 codec).

Customer can test their ISP connection speed from their home/office network to our VPN4SIP network by accessing the web site http://www.speedtest.net .

A: YES, you can. our VPN router has up to 4 ethernet port for Local LAN conection, so you can connect one to four ATA boxes or IP Phones to the router using standard network cable. Each VOIP device will automatically get a private IP from our VPN4SIP network and share the same VPN4SIP connection for concurrent VOIP incoming/outgoing calls.

A: Yes, we can do that for you too! In this way your PC must be powered on and connect to internet every time you want to make calls or receive calls. Obviously using VPN router is the most convenient and energy saving way to unblock VOIP calls for 24x7. But we respect customers request and we can provide you software VPN bridge solution, please contact us for details.

A: It depends on your current ISP connection speed (both upload and download direction) and the VOIP Codec settings in your VOIP Adaptors or IP Phones.

If customer has enough ISP bandwidth for both upload and download direction so can get full VPN connection speed (100Kbit/s upload and 100Kbit/s download) from VPN4SIP network, here is the reference about the maximum concurent calls can be made through single VPN4SIP connection:

Codec           Rate     Payload Bandwidth  Maximum Calls
G.723.1         6.4kbps  30ms    17kbps     4-5
G.729/G.729a    8kbps    20ms    24kbps     3-4
iLBC            13.3kbps 30ms    24kbps     3-4
GSM             13kbps   20ms    29kbps     2-3
G.711 uLaw/aLaw 64kbps   20ms    80kbps     1


In general, if you are using G.711 ulaw/alaw codec, you will be able to have only one call with guaranteed voice quality; if you are using G.729 codec, properly you could make up to 3-4 concurrent calls with good voice quality.

A: In VPN4SIP network, everything is dedicated:

Each VPN4SIP account is assigned with a dedicated public IP when forwarding the VOIP traffic to from VPN network to public internet;

Each VPN4SIP account is assigned with QoS guaranteed 100Kbit/s dedicated bandwidth (for both uploading and downloading direction) that isn't sharing with any other customers;

Each VPN4SIP connection is a dedicated VLAN setup VPN network so no one can sniff or monitor the ethernet traffic coming from your account;

Each VPN4SIP connection is using a dedicated listening IP and dedicated UDP (or TCP) port which isn't shared with any other customers.

A: Of course you can. But keep in mind that our VPN service is designed to use with Skype Ethernet phone adapter, Skype Wireless phone set or Skype standalone Video phone that no PC required, VPN4SIP service isn't for PC based Skype calls.

A: Absolutely YES. If you are phone service provider and want to bring VPN connection to your valued customers, or if you want to resell our VPN4SIP service to your local area, with 10 or more VPN accounts under your name, our price can go lower to 9.95USD/month per account! Contact us for terms and conditions.

A: No! VPN4SIP connection is dedicated for residential VOIP traffic usage, unreasonable activities other than VOIP calls through our VPN4SIP network will lead to the suspention of accounts without notice, and no refund will be issued in such such service abuse.

A: Please contact us by the method mentioned in our "" page, we will arrange professional people to answer any of your questions in one business day, thanks.