competition is brutal
Core?
Cisco is having to compete with novel designs that are cheaper, faster, more compact from Brocade, Huweii, Dell, etc. Huweii is predominant in Asia where IT infrastructure growth's still occuring.
As stuff moves to the cloud, fewer (higher margin) core switches are required.
Cloud companies are rolling out more flexible software-defined networking, instead of opting for traditional (i.e. Cisco) rigid hardware-defined designs.
Edge?
What's left at the edge is being eaten by lower cost enterprise competitors - Brocade, Dell, HP, Enterasys/Extreme, Alcatel, etc.
The ankle biters - Netgear etc - are all moving up in this space too.
Smart Net?
Only dummies bought Smartnet on their edge switches - (always cheaper to stock spares) and with Cisco resellers rolling out their own versions of smart net at lower cost, less is being booked on the remaining core sales.
Servers?
Cisco's done well to capture a small but profitable slice of the server business, but it's struggling to grow further vs HP and Dell, due to the main growth coming in OEM vendors - aka cloudy tin.
Conclusion?
Watch Cisco's gross margins in their quarterly reports.
Cisco has significant and systemic structural issues, it appears. The headwinds are against them.