VoIP over VPN dropping daily

Posted on 2006-06-05
Last Modified: 2012-06-27
Hello All,

Our office has recently installed a Comdial MP5000 phone system with the intentions of distributing CONVERSip EP300 SIP Endpoint phones to several of our remote branches to, of course, use the VoIP features. The problem is that I have sent two of these phones out after finally getting them to work and they are dropping the VPN tunnel constantly and phones are crucial to our business.

Here is the current network layout:
Office: Full T1 -> Netgear FVS318v3 -> Comdial MP5000
Remote Sites: DSL (768k up/down) -> Netgear FVS318v3 -> CONVERSip EP300

I understand that the Netgear routers aren't the most reliable things ever. When I began to set this all up however, I was informed that it wasn't a huge deal considering that at most I would have 6 outside phones. Does anyone know of any specific settings I need to look at to get this thing up and running for more than one day at a time? If a change of equipment is necessary, any suggestions? I see a wide array of high-end VPN routers but if I am going to have to justify spending roughly 4-5x of what I originally did I need to make sure they are flawless.

Thanks in advance.
Question by:grizzles
    LVL 36

    Assisted Solution

    VoIP will send a high volume of small packets but this should not cause a problem. I think your best approach will be to replace the Netgear devices with alternative routers.

    I would get a couple of Cisco 1800 series routers. Which specific models you get will depend on which interfaces you need (dual ethernet, ADSL or T1 for example)
    This should solve your reliability problem but also importantly will enable you to configure QoS on the VPN connection so that you can prioritise the VoIP data. This will enable the voice quality to remain high even if the VPN is heavily used.
    LVL 77

    Accepted Solution

    The Netgears do have a keep alive feature on the VPN auto policy page. I have seen this help with some other routers, however I have had lots of problems with Netgear as well. One client was instructed to download a beta firmware update that you can schedule a nightly reboot of the router. That to me indicates serious problems when you have to add that as a feature.
    I have 1 client with 6 IP phones using the Linksys RV042 VPN routers, and they have had great success, but there is no question using Ciscos would be by far your best choice.
    Make sure before spending the extra money it is not the ISP connection that is being lost rather than your router. I have used IPMonitor to try to isolate where the connection is lost. It can be set up to monitor various IP's and log dropped connections. I usually set it up to monitor a local device, the router's LAN IP, the ISP's gateway address, an Internet IP, such as your ISP's DNS, and a device on the remote site (other end of VPN tunnel).
    LVL 3

    Expert Comment

    Look into edgemarc, adtran or intertex... they all have VPN tunnels specifically desined for VoIP traffic... they will offer a garantee of service

    Edgemarc 4200 would be my recomendation

    LVL 77

    Expert Comment

    by:Rob Williams
    Thanks grizzles,

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    Looking for New Ways to Advertise?

    Engage with tech pros in our community with native advertising, as a Vendor Expert, and more.

    Suggested Solutions

    In my office we had 10 Cisco 7940G IP phones that were useless as they were showing PROTOCOL APPLICATION INVALID when started. I searched through Google and worked for a week continuously on those phones, and finally got them working. This is a di…
    As companies replace their old PBX phone systems with Unified IP Communications, many are finding out that legacy applications such as fax do not work well with VoIP. Fortunately, Cloud Faxing provides a cost-effective alternative that works over an…
    Internet Business Fax to Email Made Easy - With eFax Corporate (, you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, fr…
    Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…

    779 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    18 Experts available now in Live!

    Get 1:1 Help Now