5 SD-WAN gotchas customers want to avoid

Software-defined WANs (SD-WAN) are becoming key components of modern IT infrastructures. Because they use a centralised control function to securely direct network traffic over the Internet, they can deliver benefits such as increased application performance, better user experience and lower costs.

SD-WAN technology simplifies the management and operation of a WAN by decoupling networking hardware from its control mechanism.

As organisations look to support a hybrid workforce and cloud-native network architectures, SD-WAN infrastructure has become an important technology for enabling flexible, agile, and optimised connectivity.

Not surprisingly, demand for SD-WAN is on the rise. The SD-WAN infrastructure market grew 27 per cent in 2021 compared with 2020, to reach $3.8 billion, according to research firm IDC. The market is forecast to grow at a 19 per cent compound annual growth rate over the next five years, reaching $7.1 billion by 2025.

Deploying this technology is not without challenges, however. Here are some of the potential issues that IT and network managers might confront.

1. Limited cost savings

Enterprises expecting to cash in on the expected financial benefits of SD-WAN might be a bit disappointed.

“Early SD-WAN marketing was all about moving to hybrid WAN to save money on expensive private/MPLS networks,” said Andrew Lerner, vice president at research firm Gartner covering enterprise networking with a focus on emerging technologies. “And SD-WAN products helped people move to hybrid WANs, lowering reliance on MPLS.”

However, the promised massive cost savings never materialised for most organisations, Lerner said. “Many folks supplemented their WANs with [Internet connectivity], and then left MPLS in.”

In many regions, business-class Internet “is not a ton cheaper,” he said. In addition, as organisations go to Internet connectivity versus MPLS, they often increase bandwidth, so cost per megabit might go down, but total cost rarely does, he said.

Then there’s the cost of products. “The early SD-WAN products were relatively inexpensive,” Lerner said. “They were lightweight, and one of the key differentiators versus traditional routers was cost.”

SD-WAN hardware appliances were coming in at $500 for the hardware and $100 per month per appliance for the software license, Lerner added.

“But in the past few years, hardware and software costs have risen for a number of reasons,” he outlined. It is now common to see hardware around $1,000 per site and licensing costs of $150 per month per appliance.

Forrester Research has found that the networking and security infrastructure and operations costs of SD-WAN actually rise over time, not decrease, said Andre Kindness, principal analyst at Forrester.

“During the initial rise of SD-WAN, many vendors marketed SD-WAN as a cost savings,” Kindness said.

“In particular, the vendors’ marketing material messaged large costs savings if companies shifted their connections from MPLS to Internet. There hasn’t been a large shift from MPLS to Internet. Instead, networking organisations kept MPLS links but now use Internet links as an active connection instead of back-up one.”

2. Operating SD-WAN in a vacuum

If enterprises operate their SD-WANs in an isolated manner, without integrating the technology with other systems such as security tools, they will miss out on some important capabilities.

“As the SD-WAN market matures, enterprises are increasingly looking beyond standalone SD-WAN platforms,” said Brandon Butler, research manager, enterprise networks, at IDC. “There are a variety of integrations that SD-WAN buyers can consider to ease operational management while enhancing security and performance.”

Two of the most common integrations are SD-WAN and security, and SD-WAN and LAN/WLAN, Butler said. With SD-WAN and security integrations, common security features such as intrusion detection and prevention, deep packet inspection, and SSL inspection are natively integrated into SD-WAN platforms.

Organisations can also leverage cloud-based security capabilities that integrate with the SD-WAN platform, known as secure access services edge (SASE) architectures.

Examples of SASE functions include cloud-hosted firewall as a service, cloud access security broker, and secure Web/Internet gateway. “These may be offered directly by the SD-WAN vendor or by a third-party partner,” Butler said.

For SD-WAN and LAN/WLAN integration, some SD-WAN vendors offer integrations across the WAN and enterprise campus LAN/WLAN, Butler said. “These integrations can ease SD-WAN initial deployments and ongoing management by having centralised application policies across the WAN and LAN/WLAN,” he said.

Tags SD-WAN