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VoIP over VPN on the Comcast network

Hello everyone,

Does anyone have any real world experience linking multiple sites together over a VPN using the Comcast network?  I know there is no QoS available over the public Internet but the hope is that by staying on the Comcast network and within the same metropolitan area the voice quality would be good enough.  The proliferation of services like Vonage and Skype is causing a customer to be very interested in saving money by eliminating point to point circuits.

Thanks in advance.  All replies rated.


Re: VoIP over VPN on the Comcast network

Correct about no QOS (I guess that should be obvious, right?)  Other then that I would just set the expectation that it will be only as good as the internet, i.e. Skype.  Most of the time it should work satisfactorily, but some days it may not work at all and sometimes call quality may be poor.

I would ask the customer about the types of communication they plan.  For example inter-office may be fine because if the voip isn't working they can call back on a cell phone or use email.  If they are taking customer facing calls that cost the company money if calls are poor or dropped then I would make sure they understand the risks and take that into account.

My main problem with Comcast and other home networks is dealing with the modems and home routers. No matter what enterprise grade equipment you may place at your end points you are going to have some type of cable,wireless router combo unit to deal with.

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Re: VoIP over VPN on the Comcast network

I agree with Brandon on the modem/router/wireless combo devices that you typically deal with in residential scenarios.  For example, I have internet service from a large, well-known provider and I used Lingo for about 4 years.  Prior to that, I tested multiple VoIP providers at home to finally decide upon Lingo.  Long story short, I had little control over the built-in firewall/security functions of the wireless/combo switch/router and it was interesting that with no configuration changes my provider's VoIP services worked without issue (same for Vonage).  However, for Lingo and a couple other providers (Packet 8) - I had to put in hokie port forwarding rules to get the services to work.  So, there is always a variable there.

As for Comcast, I won't get that discussion as opinions on providers vary on many levels.  The most important thing is to know or be able to gather enough information to feel relatively certain that user's home networks are typically stable.  For example, if provider X has a reputation for going in/out but provider Y has a reputation for always being available - one could deduce that provider Y may have a better chance of providing the type of end user experience customers wants.  However, there are many factors that determine what provider is available at someone's residence - in many cases, there is only one choice, whereas in others - you have pick of the litter.

Just my 2 cents.


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