Currently we have multiple different hardware vendors performing all different parts of our layered security. Now that I think of it, we don't have more than one vendor performing security in every part of our network. (Firewalls, SIEM, antivirus, IPS, etc.)

I like Cisco and seeing what they can do with all areas of security running Cisco products is impressive. From your standpoint, would it be better to diversify the equipment to different vendors or have one manage them all. I know that Cisco might not be #1 in all categories, but when all their equipment is working together, I feel that you have a tighter network.

Scucci

In part I'd agree with Dale.

Cisco are generally superior in what they do best, routing and switching. However, often the attempts to branch into different fields and features can leave a bit to be desired. They usually design and create devices with a high level of security, however it is often seen that the advanced 'features' are less secure.

For example this months security advisory lists several vulnerabilities in 'security' features; including vulnerable IPS features, potential data leakage from a VPN and even an issue with the humble NAT. (Full advisory here)

I'm not trying to claim that Cisco devices are less secure than other manufacturers, it could easily be the case competitors are just less open regarding their bugs; and if you want to move to a single manufacturer for all devices you could certainly do worse than go with Cisco.

It is usually the case though that those specialising in a specific technology will produce a better product than generalists, providing you stick to the big boys. Best-of-breed devices usually have that label for a reason.

Good luck out there...

Like I said, dont put all your eggs in one basket (all one vendor) unless there is a strategic reason.

Multiple layers is the key, and if this can incorporate various vendor offerings the better.

I think it matters a lot (personal preference) because Cisco security products have steered away from mostly being point products several years ago.  For the past couple of years, they've focused on collaborating each security controls together to integrate with another & even escalate the security of other Cisco security solutions. 

Security no longer becomes an afterthought or a necessary evil, but a security architecture that's designed to scale to Government & Compliancy requirements (like PCI, HIPPA, SOX) which goes far beyond just a simple firewall.