I wouldn't call Cisco Systems (CSCO -0.09%) a millionaire-maker stock today. Those days are over, and the network-equipment giant is more of a wealth-preserving stock pick right now.

A strong market...

Don't get me wrong -- there's lots of room for long-term growth in the networking sector as a whole. As Cisco's own Visual Networking Index suggests, global internet traffic should keep expanding by more than 20% a year for the foreseeable future and some parts of that complex market are growing much faster.

Current and upcoming megatrends are spurring plenty of fresh growth. The Internet of Things requires tons of network traffic between sensor-equipped devices in the field and their centralized data-analysis hubs. Also, 5G wireless networks will not only support the IoT explosion, but also help consumers around the world to stream high-quality videos and music in ever-rising volumes. And those data centers at the heart of those trends are shuffling more and more data between their servers to get the back-end jobs done.

A handful of tiny worker miniatures carry a huge Ethernet plug up to an equally gargantuan network switch, ready to plug it in.

Image source: Getty Images.

... but Cisco is losing market share

The networking market is thriving and should keep doing so for many years to come. The IoT and 5G revolutions should, in fact, provide an extra short-term boost over the next couple of years. But Cisco has been losing market share to a new breed of hungry challengers in recent years, and that trend may keep a lid on the company's growth -- and on the stock's wealth-building powers.

There's no denying that Cisco faces serious challenges from Chinese networking giants Huawei and ZTE, mostly in the Middle Kingdom but also on a global level. Here in the U.S., Cisco's 5% revenue growth over the last five years can't hold a candle to the terrific top-line growth you see in more specialized networking vendors:

CSCO Revenue (TTM) Chart

CSCO Revenue (TTM) data by YCharts.

Extreme Networks (EXTR -0.54%) put together a top-to-bottom equipment vendor for the data-center market out of several astute acquisitions in 2017 and threatens to keep stealing market share from Cisco in that vivacious sector segment. Arista Networks (ANET 1.97%) built its data-center presence from the ground up with a particular focus on cloud-computing support and advanced traffic-management tools.

Like Extreme, Arista is nibbling at Cisco's heels with a small revenue take today but strong top-line growth. Both of these companies would be easier to place under the "millionaire-maker" banner than the current form of Cisco Systems.

This stock is good for a different kind of investor

The smaller networking stocks may appeal more to high-growth investors, but there's still a place for Cisco Systems. Arista is trading at 57 times earnings and Extreme is unprofitable, while Cisco trades at a mature 18 times trailing earnings and pays a generous dividend with a 2.9% yield.

This is the kind of stock you buy today and stick under your pillow for a rainy day, many years down the road. The dividends will keep coming and share prices should hold relatively steady in the long run. That's value preservation for existing millionaires, not a way to build a lot of brand-new wealth.