The extent to which mobile can be a functional substitute for fixed access is a more complicated issue, in part because of the value-price relationship. Mobile Internet access historically has been slower than fixed access, while the cost to use a mobile gigabyte of data generally is far higher than use of a fixed network gigabyte.
Nevertheless, there are growing instances where fixed and mobile Internet access are more-nearly functionally the same. Such mobile substitution has grown in the U.S. market, for example
For Deutsche Telekom customers, mobile Internet access speed--since 2014--has generally been faster than what is available on the fixed network.
Some usage scenarios already are clear enough. Where the cost of fixed network Internet access is non-economical, mobile will be the only form of access.
Where both mobile and fixed access are available, there are more use cases. With the advent of Long Term Evolution, the number of viable use cases has grown, compared to the situation where 3G is viewed as a potential substitute for fixed access.
Low usage, single-user consumers are a generic class of consumers for which mobile access using LTE could be a viable substitute for fixed access. Single-person households or users who do not watch much online video are examples.
On the other hand, multi-user households that watch significant amounts of video almost never are the best candidates for mobile Internet access substitution.
Someplace in the middle are many use cases where mobile offers might compete effectively with fixed network offers on a price-per-gigabyte basis.
It will is tough, but not impossible. Users will have to manage their own behavior, resisting the temptation to use resource-intensive apps when on the mobile network.
Substitution also will be easier in markets where public Wi-Fi or at-work Wi-Fi is plentiful.
The big question is whether future 5G mobile networks, supporting gigabit access speeds, also will be priced, on a cost-per-gigabyte basis, close enough to fixed prices to make both modes relatively full substitutes.
The other issue is mobile access in markets where fixed network alternatives are unavailable, expensive, slow or all of the above.
The converse also is true: where fixed network services are highly affordable, the value of using a mobile alternative is less compelling.
According to Ofcom, the lowest levels of mobile broadband take-up are in France (15 percent of respondents) and the United States (10 percent).
In France the widespread availability of cheap triple-play bundles of fixed voice, fixed broadband and pay-TV provides an incentive for households to have a fixed broadband service, while in the United States, relatively expensive mobile broadband data charges are likely to be limiting the use of mobile broadband as a substitute for fixed broadband services, Ofcom says.