Five weeks after Cisco Systems Inc. (CSCO) - Get Reportdisclosed John Chambers would step down as chairman in December and hand the position over to CEO Chuck Robbins, Robbins has uncorked another big move in his multi-year push to grow Cisco's software and services exposure. With Chambers (who reportedly had differences with Robbins related to his strategic overhaul) set to exit, more large deals could -- and probably are -- in store.

Robbins' latest move: A $1.9 billion ($55 per share) all-cash deal to buy unified communications (UC) software/services provider BroadSoft Inc. (BSFT) . The deal is Cisco's second-largest software purchase, trailing only its $3.7 billion January deal to buy top app performance monitoring (APM) software firm AppDynamics, and carries a modest 2% premium to BroadSoft's Oct. 20 close.

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By enterprise software standards, Cisco is paying pretty reasonable multiples: The purchase price is equal to 21 times BroadSoft's 2018 EPS consensus of $2.61 and five times its 2018 revenue consensus of $382 million. But it is eyebrow-raising in a couple of respects:

Cisco Is Buying a Rival

Cisco is buying a rival. Like BroadSoft, Cisco provides a variety of UC software products that are deployed by third-party service providers, who in turn use them to provided hosted communications services to businesses. Indeed, it was only in February that BroadSoft, which counts AT&T Inc. (T) - Get Report, Verizon Communications Inc. (VZ) - Get Report, Deutsche Telekom and many other top-tier carriers as clients, referred to Cisco as its "next closest competitor" in the market for cloud-hosted UC lines.

Cisco tries to downplay this overlap by arguing its solutions are more likely to be used by enterprises, and BroadSoft's by small and mid-sized businesses. In addition, unlike BroadSoft, Cisco sells its UC offerings to enterprises for on-premise deployment; it competes in this market with the likes of Microsoft Corp. (MSFT) - Get Reportand Avaya. And BroadSoft, unlike Cisco, gives service providers the option of using the company's own cloud platform to deliver UC services based on its software.

Cisco Could Pinch its Channel Partners

Cisco is stepping on the toes of its channel partners, some of whom are less than thrilled about the deal. With BroadSoft's solutions heavily used by telcos, partners who have been delivering UC services to businesses with the help of Cisco products are worried that the creation of solutions for service providers that pair Cisco's offerings with BroadSoft's will make life harder for them. Even if they're also able to use BroadSoft's products.

If Cisco is worried about such channel conflict, it's not showing any signs of it. Instead, the company touts how pairing Cisco's "leading meetings [software], hardware and services portfolio" with BroadSoft's product line will let it "offer best-of-breed solutions for businesses of all sizes and deliver a full suite of collaboration capabilities."

If Cisco is willing to tolerate some product overlap and/or ruffle the feathers of channel partners when making a 10-figure acquisition, it opens up a lot of possibilities for future deals. Particularly when one also considers how, since Robbins became CEO in mid-2015, Cisco has made big acquisitions in fields ranging from APM software and cloud-hosted IoT services to collaboration software and security tools that integrate with its hardware.

Here are some of the other software names that could be in Cisco's sights if the company is willing to think big and isn't troubled by some potential overlap or channel conflict:

Red Hat Inc. (RHT) - Get Report -- If Cisco wanted to make a serious play for becoming an essential infrastructure software provider for enterprises and telcos, it could do no better than to buy Red Hat. Though best-known for having the most popular version of Linux for enterprise servers -- and Linux is still taking server OS share -- Red Hat's product line now also covers popular middleware, storage platform software and cloud management software, among other things. Plenty of synergies exist with Cisco's product line, although there is a risk that some of Red Hat's OEM partners wouldn't be thrilled about a deal.

Working against a deal: Red Hat is currently worth $21.6 billion, and trades for 6.7 times its expected fiscal 2019 (ends in February 2019) sales. More value-oriented Cisco investors would undoubtedly feel some sticker shock.

Splunk Inc. (SPLK) - Get Report -- Splunk remains the top provider of software for analyzing the mountains of log and machine data that corporate IT systems throw off. With IT operational intelligence and security two of the main use cases for Splunk's products, the company would fit well with Cisco's efforts -- pursued in part via the AppDynamics deal and the launch of Tetration software platform -- to give businesses a comprehensive set of tools for managing and analyzing the performance of their IT infrastructures.

Like Red Hat, Spunk would be a big fish to swallow. The company sports a $9 billion market, and trades for about 6 times its expected fiscal 2019 (ends in January 2019) sales.

FireEye Inc. (FEYE) - Get Report -- FireEye, long a subject of Cisco M&A speculation, owns a slew of security technology and services assets that could appeal to Cisco. These include malware-analysis software, endpoint protection software, threat-intelligence services and forensic services for responding to a major security breach.

There is some overlap with existing Cisco security solutions in areas such as malware-analysis and threat intelligence. But making FireEye's differentiated offerings available via Cisco's massive salesforce and channel partner base could pay off. And its price tag is reasonable: FireEye carries a $3 billion market cap and trades for just 3.6 times a 2018 billings consensus of $841 million.

CyberArk Software Inc. (CYBR) - Get Report -- Like FireEye, Cisco competes to a degree with CyberArk. But CyberArk has established itself pretty well as a leader in the privileged account security software market -- that is, the market for tools that set policies for and prevent unauthorized access of employee credentials that can be used to access sensitive data. With quite a few hacking incidents stemming from lax controls over securing such credentials, the privileged account protection market has been seeing brisk demand.

Following multiple selloffs caused by earnings disappointments, CyberArk only sports a $1.5 billion market cap and trades for 4.9 times its 2018 revenue consensus. But the company maintains its leadership position, and sales are still expected on average to rise 35% this year and 20% next year. Expanding the company's security software footprint has been a Cisco priority, and buying CyberArk gives Cisco an intriguing and not-too-expensive way of doing that.

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