Resource Library

Cisco Unified Communications Manager (CUCM) includes a feature called "call throttling" that denies new call attempts when the system is in a state that may lead to delayed dial tone. The Real Time Monitoring Tool (RTMT) will generate a code yellow alert when call t...

While most organizations have not yet fully (or in many cases even partially) adopted cloud computing, the trend is growing in all but the smallest businesses.

Anyone who’s managed switches over the years knows that the Spanning-tree protocol (STP) is both the best and worst thing to ever happen to the data center at layer 2 of the OSI model. On the plus side, the Spanning-tree protocol is what first allowed us to create redundant paths within our switching infrastructure, making our data center much more resilient to outages than ever before. Anyone who’s experienced a “broadcast storm” knows the full value of Spanning-tree in the traditional switching environment. We’ve also seen many improvements in Spanning-tree over the years to make it work faster and more efficiently (i.e. Rapid Spanning-tree, Bridge Assurance, and many others).

Cisco IP phones support a variety of different audio codecs. In this post, I will explain some of the differences and explain which versions of CUCM and the Cisco IP phones support the various audio codecs. Audio codecs are responsible for sampling human speech (a s...

In support of software-defined networking, Cisco has introduced several products to strengthen networks and meet the increased demand for flexible and cost-efficient solutions. The Cisco SDN solution in the data center is ACI. Outside the data center the primary Cisco solution is DNA.

The value of IT certifications has grown considerably over the last decade. Examine the evolution of certification trends, see the top-paying certifications and learn how decision-makers are struggling to hire certified employees.

This week we'll review the IPv4 Address Classes including subnet masks, examples of Class C, Class B, and Class A subnet masks, and planning IPv4 addresses.

Early one morning, an engineer end user discovered that the Engineer servers were unreachable, and he didn’t know if he could reach the Internet. The administrator investigated the user’s PC with the IPCONFIG /ALL command and verified that the PC was a DHCP client, but it had received an address from the Accounting DHCP server, not the Engineering DHCP server.

Call Admission Control (CAC) is often times included as part of the same topic as Quality of Service (QoS), when in actuality CAC is a separate and complete topic itself. QoS is defined as traffic engineering on a packet switched network. This definition means movin...

When integrating a Voice over IP (VoIP) system into an existing network it is very important to have a good understanding of how much bandwidth is utilized for each call on the network. For most people, just starting out the bandwidth calculations can be a very daunt...