Cisco warns of unpatched AsyncOS zero-day exploited in attacks

Cisco warned customers today of an unpatched, maximum-severity Cisco AsyncOS zero-day actively exploited in attacks targeting ...
Ars Technica

Nation-state hackers exploit Cisco firewall 0-days to backdoor government networks

Hackers backed by a powerful nation-state have been exploiting two zero-day vulnerabilities in Cisco firewalls in a five-month-long campaign that breaks into government networks around the world, ...
Network World

Chapter 3: Routing Calls over Analog Voice Ports

Describe the various call types in a VoIP network. Configure analog voice interfaces as new devices are introduced into the voice path. Configure dial peers so you can add call routing intelligence to ...
Network World

Allow Both TCP and UDP Port 53 to Your DNS Servers

Security practitioners for decades have advised people to limit DNS queries against their DNS servers to only use UDP port 53. The reality is that DNS queries can also use TCP port 53 if UDP port 53 ...