Though many of them are unlikely to see high long-term growth rates, telecom equipment suppliers should get a top-line boost over the next few years from 5G network rollouts that are expected to start in earnest in 2020.

And with a lot of these names currently trading at discount valuations following many years of seeing little to no growth, 5G rollouts could eventually provide a lift to their shares.

Finnish telecom equipment giant Nokia (NOK - Get Report) , for example, trades for just a little over 1 times a 2020 revenue consensus estimate of $26.5 billion. Swedish peer Ericsson (ERIC - Get Report)  trades for 1.1 times a 2020 revenue consensus of $24 billion.

EPS multiples, though not particularly high, don't look as cheap: Nokia and Ericsson respectively trade for 13 and 16 times their consensus EPS estimates. However, just as chip companies with high fixed costs see their earnings grow much faster than their revenue during an up cycle (and see the opposite happen during a down cycle), the operating leverage in Nokia and Ericsson's business models should allow them to deliver strong earnings growth in the event that they see moderate revenue growth as 5G rollouts pick up.

Nokia and Ericsson have each announced dozens of deals with carriers to supply equipment, software and services for 5G deployments. And as many others have also noted, the U.S. government's attempts to dissuade friendly nations from using 5G equipment supplied by China's Huawei and ZTE could allow Nokia and Ericsson to land a few more large 5G deals than they otherwise would have.

Optical networking equipment suppliers Ciena (CIEN - Get Report)  and Infinera (INFN - Get Report)  also sport moderate valuations. Ciena goes for 1.5 times a fiscal 2020 (ends in Oct. 2020) EPS consensus of $3.8 billion, and 14.5 times a fiscal 2020 EPS consensus of $2.56. Infinera, which has been losing money in recent years but is expected to return to profitability next year, trades for just 0.65 times a 2020 revenue consensus of $1.43 billion.

As 5G radio deployments spur larger telco investments in mobile backhaul and core networks, so that they don't become bottlenecks as mobile data rates and data traffic surge, spending on optical transport and switching gear from the likes of Ciena and Infinera (and for that matter, Nokia) should grow along the way. Ciena and Infinera, it should be noted, also have some exposure to capital spending from cloud giants, via their sales of data center interconnect (DCI) transport systems.

Juniper Networks (JNPR - Get Report) , meanwhile, is (along with Cisco Systems (CSCO - Get Report) , Nokia and Huawei) a leading supplier of routers for carrier networks, and also supplies Ethernet switches and software to telcos. And like Ciena and Infinera, it has some exposure to cloud giants, in its case via switch and router sales. In time, 5G should drive greater spending by carriers on routers needed to move traffic across their metro and core networks.

Juniper currently gets about 40% of its revenue from traditional service providers, 25% from cloud service providers and the rest from traditional enterprises. Its shares trade for 12 times a 2020 EPS consensus of $1.91, and 1.8 times a 2020 revenue consensus of $4.6 billion.

Generally speaking, traditional telecom equipment firms don't appear likely to deliver big returns in a short amount of time. For many of these companies, the revenue lift that comes from 5G rollouts will be a fairly gradual one. And certainly, would-be investors should stay mindful of company-specific issues -- for example, Infinera's current red ink or Juniper's recent routing share losses.

However, the low multiples sported by these companies do give them some margin of error. And should (as is possible) 5G deployments boost their top lines more than current analyst estimates project, those multiples could easily rise a bit.

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