The telecom industry has been trumpeting 5G network slicing for a couple of years now, saying carriers will be able to make money by selling “slices” of their networks to different enterprises for their exclusive use.
But then, along came the private wireless network craze. It’s being spurred in the U.S. largely by the auction in 2020 of Citizens Broadband Radio Service (CBRS) spectrum.
With spectrum, an enterprise can run an LTE or 5G private wireless network to get broadband connectivity, similar to a public wireless network, but which the enterprise can completely control.
Don Alusha, a senior analyst at ABI Research, said, “Private networks typically have their own authentication and authorization of devices and equipment. Whereas 5G slicing customizes network services according to different ranges of granular requirements, and reliability is guaranteed by service providers.”
Why would a company want a network slice, when it can just create its own private network?
Both Ericsson and Nokia are working on technology for private wireless as well as network slicing. And executives from the companies talked about the two.
Paul Challoner, VP of network product solutions with Ericsson North America, said 5G network slicing will require a 5G standalone (SA) core and SA devices. Only T-Mobile in the U.S. currently has a 5G SA core, while AT&T and Verizon do not, yet. Dish Network is building it 5G network from scratch, so it will immediately have an SA core, and Dish is integrating the technology for network slicing from the get-go.
Challoner said network slicing will provide isolated network resources with security and tailored service level agreements (SLAs) for each enterprise.
But it’s unclear how many slices a mobile operator will be able to offer.
David Eckard, VP of strategy and technology for Nokia in North America, said the capacity question and number of slices depends on the use cases. But he said, “I think it’s going to be a handful.”
Challoner said, “Every network has a capacity, which is determined by the spectrum and the number of radios you have. As long as I have enough physical capacity in my overall network, I can partition it off for use by a client.” He also pointed out that network slicing technology is being developed to work on a dynamic basis. “If the enterprise is not using it, I can use it for other purposes,” said Challoner.
Alusha said private networks are “a static deployment,” while network slicing, on the other hand, “is more associated with dynamic deployments.” But he added, “How do we make sure the processes of one enterprise are isolated in such a way there’s no interference with other enterprises?”
In contrast to network slicing, which is based on a carrier’s full network, private wireless networks are often more localized.
Karim El Malki, president of Athonet, said private wireless is great for an enterprise that has a need for its own wireless network that is fully controlled by its IT department. It will provide secure connectivity within a prescribed area such as an airport, school or factory. These types of organizations have typically relied on Wi-Fi until now.
Private wireless can be a huge upgrade from Wi-Fi, and the cellular technology with private wireless can support companies that want to process all their data on-site and keep everything secure.
But private wireless networks might be a concern for enterprises that have multiple business locations that need to communicate with each other. In this case they’re dealing with a wide area network (WAN), rather than a local area network (LAN). “A private network is deployed within some clear boundaries of a given facility,” said Alusha. “Within that setting it works really well. Whereas with network slicing, operators already have infrastructure deployed.”
Challoner said network slicing has an advantage in that regard. “If I want my employees to go outside, seamless roaming with the public network is a tremendous advantage. I want that mobility with the WAN.”
While network slicing may have an advantage with roaming, El Malki doesn't think it has an advantage in terms of a WAN.
He said Athonet can serve up private wireless networks across a national footprint, for example a retail chain. Athonet treats it almost like a Wi-Fi set-up, only it’s using cellular CBRS spectrum and LTE technology. The company provides each outlet with a customer premises device that self-configures. “We’ve cloudified and automated the whole deployment, put out a small cell, it connects to the cloud, data stays local,” said El Malki. “The private wireless objective is really to make it possible for thousands of stores or locations to get their private networks and have people move between them and maintain private connectivity.”
Athonet’s customer premise device comes with a SIM card, or the company even supports eSIM, and its core network manages all the SIMs.
What if network slicing is a dud?
Vendors such as Ericsson and Nokia are investing heavily in network slicing, and they want to see a return on that investment. Alusha said some people feel that if network slicing doesn’t come through, then the promise of 5G will have failed because it’s been touted as a big way for operators to get new business revenues.
Perhaps enterprises will make their choices based on the cost difference.
“Private networks tend to be high-cost solutions, particularly if extended to the wide area network,” said Alusha. “Whereas slicing is relatively low-cost because vertical industries use operators’ deployed network assets.”
But Challoner said it’s too difficult to say which will be most cost-effective: private wireless or network slicing. He said there are “too many dependencies,” including the size of the enterprise, the spectrum and the data requirements, to name a few.
El Malki said, “Network slicing is the operator play for their central network. But there’s limitations due to the complexity, and you cannot have that many slices. It’s not infinitely scalable.”