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5G and SD-WAN could provide reliable, alternate connectivity

5G and SD-WAN could develop into an alternative connectivity option that offers high speeds and low latency to geographic areas and remote workers with limited connectivity options.

Fifth-generation wireless is an evolution of cellular radio network standards designed primarily to provide the potential for higher access speed and greater total capacity per cell. It also promises to reduce the latency associated with cellular connections. In one form, 5G can even provide an alternative to wireline connections to homes and business sites.

5G discussions include a maze of standards, a lot of talk about the progress of standards, and many new technology elements, such as network slicing and millimeter wave. But enterprises shouldn't be concerned about these terms and issues because they relate to building 5G networks, not using them.

Software-defined WAN (SD-WAN) is a virtual private network technology designed to use an overlay network to create a VPN that doesn't rely on advanced features of IP networks, like MPLS. Overlay SD-WAN can ride on Carrier Ethernet, IP and MPLS, the internet and cellular radio technology, including 5G. Because SD-WAN is independent of the underlay network -- or the transport network -- it can extend a company VPN to any site with a useful data connection, regardless of the technology. It's the stepping stone to universal, ubiquitous VPNs.

The weakness in this happy story of VPNs everywhere is the lack of effective, universal transport connectivity. An overlay network needs something on which to overlay -- some transport system that reaches every business site at data rates and quality-of-service levels consistent with the needs of local applications and users.

SD-WAN over the internet is useless without good internet access. For many smaller rural or international sites, internet connectivity is based either on limited copper loop technology or early-generation cellular services -- with data rates less than a fifth of the typical connections offered to the home in many countries. 5G could fix that.

5G wireless market development
This timeline shows the expected development of 5G adoption and spending.

5G provides options for thin-route areas

In thin-route areas -- geographic areas with lower bandwidth because network users are sparse and providing connectivity is likely less profitable -- 5G cellular service offers network operators the opportunity to deploy mobile services. But if the service is paired with a dongle or 5G hub, it can also supply an alternative to fixed-line connectivity. Many factors affect 5G data rates, but the technology is capable of speeds from five to 25 times that of 4G. That would be faster than most DSL connections, and it could open VPN membership to millions of sites that can't get suitable internet as a foundation for SD-WAN.

Truly thin-route sites today may even rely on satellite broadband for internet, but satellite connections are typically slower than consumer internet services and introduce a quarter-second round-trip latency that can kill many applications. 5G has lower latency than 4G, so it creates both faster and better connections. Further, IoT in thin-route sites might be impossible over satellite connections, but 5G makes it practical.

Organizations should consider 5G and SD-WAN applications as opportunistic for now -- not something on which an enterprise network planner can depend.

Mobile 5G services also offer the potential for portable offices and ad hoc connectivity during natural disasters. Any 5G connection that can support internet access can host SD-WAN services and provide what looks like a full partnership in the company VPN. Such a connection could empower public safety workers on site, back up a company office after a fire or flood, or provide service to a sporting event venue, concert or conference. The same capabilities make 5G mobile services a strong candidate to back up traditional wireline connections to offices -- a role 4G already plays with limited bandwidth. 5G would eliminate the bandwidth limitation.

Millimeter wave enhancements

As strong as the 5G and SD-WAN connection is for the mobile form of the service, another 5G service may offer even better SD-WAN support. 5G supports millimeter wave frequencies that can transport hundreds of megabits to fixed-antenna locations. If an office pairs 5G with a millimeter wave hub and antenna, and if a fiber-to-the-node installation is paired with another antenna, the 5G and FTTN hybrid can act as the substitute for wireline connections over a distance of several miles. That makes 5G and FTTN a viable high-speed broadband option in suburban and urban areas -- one with a lower cost per subscriber and a better chance of deployment at acceptable cost levels than fiber-to-the-home or office.

5G with FTTN expands the value of 5G as a backup strategy. Where the 5G and FTTN nodes are in place, it's fairly simple and fast to set up the antenna-hub combination to create a millimeter wave connection. As a backup, this combination could offer connection continuity at the same speed and latency as wireline. As a temporary connection to a mobile or portable site, it could bring workers and users at that site into the VPN as full-fledged users, with no application limitations.

5G issues and deployment reality

You probably notice the would-and-could qualifiers on most of these statements. 5G comes with its challenges, not the least being that neither 5G service nor 5G equipment is widely available -- particularly in the thin-route locations where it offers the most value. Even in areas where 5G services could quickly earn a return on operator investment, deployment will likely take years to mature. As such, organizations should consider 5G and SD-WAN applications as opportunistic for now -- not something on which an enterprise network planner can depend.

Another 5G issue is the cost and performance of the service. While the 5G standards would support as much as 100 times the speed of 4G, few believe these speeds will be widely available, if at all. Operators simply haven't deployed enough 5G to determine just how fast either mobile or millimeter wave 5G will be, or how much it will cost. That also makes it difficult for enterprise network planners to plot their 5G and SD-WAN strategies.

5G and SD-WAN are both works in progress. Competition in the SD-WAN market is particularly acute, and changes in the technology are virtually certain. Even standards-bound 5G is adapting to market conditions. Thus, the industry will resolve most of these issues, perhaps quickly. Operators have deployed 5G in both mobile and millimeter wave form, and for some areas 5G and SD-WAN may already be practical. Certainly, it's a combination both operators and enterprises should watch carefully.

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