Point Of Sale And Wireless Wans
Modern point of sale systems are heavily reliant on highly available networks. There are a multitude of dependent functions that the Point of Sales (POS) systems service that must be executed or initiated with each transaction. First is the obvious; a fast, efficient, and complete transaction that is a part of the customer and employee experience at check-out. This can involve the ability to access pricing, payment processing, and receipt/invoice printing as well as updates to stock-keeping and inventory management. Returns processed via POS terminals also generate potential traffic to reverse logistics, financial, inventory allocation, replenishment, and omni-channel systems.
With all of these dependencies, it’s key that your point of sale systems are able to talk to back-end systems and payment processors without delay. All that said, a popular initiative with many companies is to rely more heavily on 4G LTE data and to look toward 5G wireless technologies to provide that connection from POS to back office systems as part of their WAN strategy.
This paradigm provides a significant amount of value but comes with some very important caveats that require recognition as you consider a Wireless WAN as an element of your POS data transport strategy.
If you listen to the carriers, LTE and 5G is nearly ubiquitous, provides highly available and fast connectivity everywhere you want to be and is inexpensive to install and maintain. As we’re finding in recent congressional hearings on the topic; while there are elements of truth to these claims, there is also a significant gap between the marketing and reality.
Let’s look at some of these claims vs. reality:
4G/5G coverage is ubiquitous. While the key providers of cellular services have antennae and backhaul networks in place to provide very wide coverage, these technologies still rely on radio frequency signals that work best in situations where the local device has a clear “view” of the tower. This effectively reduces the availability of a useable signal in a given coverage area. The aiming of the antenna elements on both tower and customer equipment must align, the signal must be accessible from within your internal space or you must plan with facilities or property management for additional antenna elements, whether inside your building or via external mount. (this is especially difficult in multi-tenant buildings/malls where access to the roof or an external wall is not available). A key part of a 4g/5g strategy involves a survey of the available wireless signal at the exact point it will contact your systems. This survey should include signal strength, noise, and delivered network bandwidth, if possible. Establishing a minimum standard for each of these parameters will help assure that you are getting what you need from the solution. When all is said and done, there are still some very significant gaps in 4G/5G coverage at the site level that must be identified and remediated, if possible.
'A key part of a 4g/5g strategy involves a survey of the available wireless signal at the exact point it will contact your systems"
4G/5G is highly available. Let’s assume you have found a provider and they are providing a strong signal at your location that is useable from a network perspective, you’re not quite done. As noted, the network is being provided by a radio signal using a publicly shared antenna and backhaul network. Radio noise from a myriad of sources (Motors, vehicles, solar activity) can alter the quality of the connection on a moment by moment basis. The number of connections on the tower your signal is connected to can alter the amount of bandwidth available and the latency of the connection as well. It’s a common occurrence in retail for the Wireless network to work flawlessly during store build-outs and then fail to perform when 150 people with phones in hand have queued up for Grand Opening and are all connected to “your” tower. This is the key issue with using 4G/5G as your primary network connection. It’s subject to a wide array of issues that affect its quality, availability and therefore, usability. For solutions other than Point of Sale, this may mean that it is still a viable solution, but low reliability at checkout is a non-starter for most organizations.
4G/5G is less expensive. Many additional caveats here. Most carriers charge for bandwidth use either on a direct use or pool + excess plan. If you exceed your pool or use too much data, the charges can go quite high. The simple fact that usage is chargeable also introduces the issues of cost variability into the decision process vs. the fixed cost of most broadband or similar technologies.
4G/5G technologies certainly have a place in the conversation about how to backhaul your point of sale data, but it’s important to understand the risks and rewards associated. A common approach is to utilize a copper or fiber-optic based network as primary for POS and to utilize a 4G/5G solution as a failover or SD-WAN alternative to maintain a network path in the face of failure on the primary network path.