With all the discussion about the positive impacts 5G can have on internet access for individuals and businesses, it’s vital that network engineers keep in mind that 5G’s not the only cellular option for enterprise WANs—4G already delivers many of those benefits.
Nemertes did research with organizations that have made significant commitments to 4G-based wireless in their WANs and identified four common use cases across the organizations. Each of those uses will be improved in several ways with the coming broad availability of 5G. Let’s take a look.
Get new sites online fast
When it can still take three months or more to get a new MPLS connection pulled, and weeks to get an Internet link activated, wireless WAN (WWAN) is a great way to get a branch up and productive as soon as possible. One professional-services organization noted that as soon as people had chairs and desks, IT was able to provide them with a connection to the enterprise WAN via a site-to-site IPsec tunnel across 4G.
Instant-on starter connectivity can also power instant-on resumption of access for relocated employees. As soon as it is powered up in the new office space, the WWAN router can bring a workgroup relocated from one office building to another back online.
Wireless backup
This is perhaps the best-known use case and most widely adopted strategy for using a WWAN. Organizations in ex-urban locations with scant choices for connectivity have embraced WWAN as a backup for wired connectivity. When the wired link goes down, the wireless one is put in service.
Again, tunneling a connection to the WAN is the usual model. However, direct internet connectivity is growing in popularity as cloud adoption also grows; more than half of the average company’s workloads run in one cloud or another instead of a company data center. One state agency Nemertes interviewed started in this model but is contemplating a switch to WWAN as its primary connectivity given that speeds are sometimes better, and reliability, too, in the locations they serve.
Bursting capacity
As with emergency bandwidth, so with extra capacity. In this scenario, the cellular service is established but basically unused except at need. In this case, need means sustained traffic surges that cause performance degradation on the primary connection or that simply exceed its capacity. One retailer Nemertes interviewed uses WWAN for both failover and bursting, regularly employing it as bursting capacity during holiday seasons when traffic peaks.
Primary connection
Wireless can also be used as the sole technology for WAN connectivity, replacing conventional wired links entirely. Organizations that succeeded with this model were usually replacing aging copper plant—DSL lines, T1s, fractional T1s, , paired T1s—and often in areas outside urban centers and first-ring suburbs where wired connectivity runs more scarce or more expensive.
Pros and cons
For companies pursuing WWAN in one or more of these four use cases, the pros were clear and consistent:
- Near-ubiquitous geographic availability of 4G LTE, often from multiple providers
- Instant-on access
- Bandwidths exceeding older and low-end wired connectivity
- Similar or better reliability for the locations served
The cons were also consistent:
- Limited availability of a wired pricing model (a flat monthly fee for a set speed, regardless of how many bits are transmitted)
- Higher cost compared to the wired services being replaced (in most cases the price per megabit-per-second dropped, but the absolute cost rose)
- Problems in a few locations with antenna placement due to construction materials and the location of wiring closets
- Avoiding usage caps and speed throttling
By-the-drink pricing was one of the most commonly cited drawbacks to WWAN among organizations Nemertes interviewed.
5G brings network slicing, wired pricing to WWAN
As it becomes a more broadly available, 5G will bring welcome improvements to the world of WWAN. Higher speeds and greater reliability are two, but an important third one is network slicing, which allows carriers to control how much capacity a given customer can consume on a shared base station. With slicing in place, carriers will be able to make capacity promises to enterprise customers and have the means of enforcing them.
At a minimum, slicing can be used to implement fair-share usage, preventing the demand of any one customer from starving out others who use the same access point. It can also partition off capacity for fixed-wireless enterprise customers from capacity serving the general public.
In any of the four use cases outlined above, higher speeds, better reliability, and meaningful capacity guarantees will be welcome improvements over the state of the art. As importantly, network slicing will be key to carriers making wired-like pricing broadly available by enabling the level of traffic engineering they need to do so.
With wired-like pricing and 4G levels of geographic coverage, 5G WWAN will become a standard option for most organizations to consider alongside wired connectivity in any of the above use cases.
Copyright © 2021 IDG Communications, Inc.
