Internet data packets have several layers of data.
The "mask" being referred to is the IPv4 address the packet originates from. You can alter it to make it look like it came from somewhere else by changing the mask, which is what translates the intra addy to the outer one, sort of.
I'm not the greatest at explaining this stuff...
I work as a network engineer, so I know how IP works.
Im trying to understand what "mask" is supposed to mean, because that isnt terminology I am used to. Unless people are talking about "masquerading", which is terminology I have seen when using Linux as a router, but sounds like another way to say NAT.
But I dont think Ive ever heard of any residential ISP classify different types of traffic and shape or police them differently on an individual service basis - that requires a lot of grunt in the BRAS or LNS. There have been discussions about doing that on a network-wide basis in the US, ala network neutrality, but thats a commercial play between network operators and content providers and not at all something intended to benefit the end user (except when the content provider agrees to pay the network operator to provision or allow more bandwidth to improve the end user experience). In my experience, ISPs will typically just count all traffic equally and shape or police your service to x speed. Maybe some niche ISPs do it... Would be interested to hear of any specific examples so I could look into it.
So as I understand it, and I have built and run access level ISP networks and infrastructure in my time, simply using a VPN isnt going to somehow magically make you avoid what ever traffic shaping/policing your ISP implements. There are still IP packets coming from your broadband service which count towards what ever throughput quota your service is assigned.
Otherwise, a VPN is just a VPN. Its not "masking" anything in any kind of special way, its just doing what a VPN does - encapsulate your traffic and encrypt it in transit to some other location. No different to a corporate VPN, just maybe with a slightly more user friendly interface wrapped around it. Any other suggestion is just marketing BS that all of these VPN companies come up with to justify their existence IMO.