Venture capital investments for wireless, telecom start-ups are down.
Company regains, upgrades e-mail and Web security software.
Bouncing e-mails cost businesses $5 billion annually, according to IronPort.
Special Focus: Start-ups seeking to challenge the dominance of complex network management suites draw rounds of funding.
Antispam, content filtering, antivirus bundled.
MIT conference-goers assert that phishing is the worst spam problem.
Aims to keep up with new strategic applications.
