Cisco, moving to expand the reach of security services it can provide, acquired privately held Okena, Inc. in an all-stock deal estimated at $154 million.

Okena provides network security software that identifies and prevents problems before they occur and includes threat protection for desktops as well as servers, Cisco said.

The deal will enable Cisco to cover both network and so-called endpoint security needs, said Richard Palmer, vice president and general manager of Cisco’s virtual private network and security business group. “By removing endpoint vulnerabilities, Okena’s preventive software solution enhances the overall security, availability and integrity of corporate networks,” he said in a statement.

Cisco stock closed down 73 cents, or 5 percent, to $13.86 Friday.