Resource Library

While the Internet uses IP addresses assigned by an Internet authority such as the American Registry for Internet Numbers (ARIN), there are too few of these numbers to uniquely identify the millions of computers and computing devices in the world. Therefore, most enterprises use private addresses which allow them to identify the aforementioned computers. Of course, these IP numbers cannot be allowed on the Internet because all private networks use the same ones so there would be vast overlapping of addresses, and the addresses are not compliant anyway. Therefore, it is necessary to change the identity of a private host to a legal public host. This process is called Network Address Translation (NAT) and may be implemented on Cisco firewall products and Cisco routers. The firewall device(s) at the Internet demarcation point is by far the more popular way to implement NAT, but routers are used in small offices or small-to-medium-sized networks in which a separate firewalling solution is not possible or affordable. The focus of this paper is on the router-based NAT solution.

The process of learning how to subnet IP addresses begins with understanding binary numbers and decimal conversions along with the basic structure of IPv4 addresses. This paper focuses on the mathematics of binary numbering and IP address structure.

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.

Moving data from one networked device to another requires several different functions. Each function has its own protocol or protocols that define how it is accomplished. Also, the process of delivering data from one device to another can vary. The main factor in data delivery is determining whether the two devices are directly connected or remotely connected.

Moving data from one networked device to another requires several different functions. Each function has its own protocol or protocols that define how it is accomplished. Also, the process of delivering data from one device to another can vary. The main factor in data delivery is determining whether the two devices are directly connected or remotely connected.

Occasionally I am asked to configure the ability to block calls based on Caller ID. Prior to Cisco Unified Communications Manager (CUCM) v8, the only way to block these calls was to configure voice translation rules and profiles on the gateway receiving the calls. This has changed in CUCM v8 with the introduction of an additional parameter in translation patterns: Route Next Hop By Calling Party Number.

License provisioning has always been a bit of a challenge in the CUCM environment. Prior to CUCM v9.0, licensing was managed on a per-cluster basis with each cluster requiring its own license files that were tied to the media access control (MAC) address of the cluster’s publisher. This approach to license management was limiting in the fact that one cluster might have unused licenses while another cluster may be at its limit and sharing between clusters was not possible.

Border Gateway Protocol (BGP) is a fascinating protocol because there are a lot of things that can be done with BGP. However, there has always been an issue with BGP, which is convergence (the time the network or protocol takes to accept change). BGP was designed for scale, not speed, so it’s something that we’ve had to tolerate from its inception.

For smaller companies, configuring a dial plan to account for variations in dialed numbers is often not a problem. However, companies that are larger and more global in nature encounter a number of issues when designing their dial plan approach.

Where should you apply the CSS, and why are there two places to apply it? One approach is to pick one of the parameters and apply the permissions there. Quite often, an administrator will pick the phone-level CSS and configure it there so that it applies to all calls made from all lines. The goal is to specify what partitions are allowed to be called. 

As I’ve stated before, I like Border Gateway Protocol (BGP). I think it’s an interesting protocol, and yes — it’s complicated, but I guess that part of why I like it. There are a lot of knobs to tweak in BGP, maybe too many, but that’s another post. Anyway, we are now running BGP version 4 and it has had extensions written that support more than just IPv4 unicast routing. We now have IPv4 multicast, IPv6 unicast and multicast, VPNv4, VPNv6, and a few others.

Cisco provides a wide array of connectivity and isolation tools within the datacenter. This white paper addresses Virtual Routing and Forwarding (VRF), which is a Layer 3 isolation mechanism for routing protocols.

What is PBR? Policy-Based Routin (PBR) is the process of using a route map to match on something more than the destination and then defining the path out of the router based on those conditions. PBR could match on destination only, but typically we would match on more. PBR is considered to be an exception to the RIB and is looked at before examining the RIB.

Now that we are moving towards IPv6, the logical move would be to also run OSPF for that protocol suite, which makes sense and reduces the learning curve for implementation and support. But, that would mean that you have to run two OSPF processes — one for IPv4 unicast and one for IPv6 unicast. That means two sets of policies have to be applied, including security for OSPF itself. Running OSPFv3 for both IPv4 and IPv6 reduces the number routing protocols and the configuration that goes with that. It makes it easier to implement policy in a consistent way for both protocol suites.

While there are differences between the IP Multicast configuration in the IOS and the Nexus OS, the Protocol Independent Multicast (PIM) protocol remains fundamentally the same. If you feel comfortable configuring Multicast in the IOS, you should be able to acclimate fairly easily to the changes in the Nexus OS.

Multicast Sparse Mode and its derivatives are supported in the Nexus OS. This white paper explains how it has been implemented in the Nexus platform to provide optimum performance in both virtual PortChannel and FabricPath environments.

Like it or not, Internet of Things (IoT) is upon us. There are a number of factors that will impact its adoption rate, and the inevitable privacy (or lack of) discussions will likely happen sooner than later. This is going to change the world as we know it, in many cases for the better. But we will need to keep an eye on the extent to which it invades our personal lives if it is going to be the positive force it has the potential to be.

This paper covers the configuration of IP Multicast with Multiprotocol Label Switching (MPLS) including the basics of Multicast with the Group Encrypted Transport VPN (GETVPN).

A Dynamic Multipoint Virtual Private Network (DMVPN) can be used with other networks like Multiprotocol Label Switching (MPLS), but streaming multicast is accomplished quite well using "Default" and "Data" Multicast Distribution Trees (MDTs) with MPLS.

Cisco Unified Computing Solution (UCS) is a very popular and powerful solution. Cisco continues to provide updated UCS management options for the full range of data center installations.

The first big push toward implementation of IPv6 was mobile devices. Now, one of the driving forces is the Internet of Things. As the name implies, this means everything, including machine to machine communication (M2M).

This paper explains uplink strategies for traffic coming in and out of a Cisco Unified Computing Solution (UCS) chassis. An uplink can be Ethernet, Fibre Channel, or FCoE and is a physical connection on the FI that leaves the UCS domain directed away from the B Chassis.

Switches play a vital role in moving data from one device to another. Specifically, switches greatly improve network performance, compared to hubs, by providing dedicated bandwidth to each end device, supporting full-duplex connectivity, utilizing the MAC address table to make forwarding decisions, and utilizing ASICs and CAM tables to increase the rate at which frames can be processed.

On February 17, 2015, Cisco announced changes to the existing voice and video certifications and detailed the new collaboration certification portfolio. This white paper provides an overview of the changes to Cisco certifications with respect to voice and video, outlining dates, and deadlines that may affect your certification process.

When properly utilized, VLANs and trunks provide flexibility, stability and ease of troubleshooting. This paper provides technical details about VLANs and trunks, along with design options at a basic to intermediate level. Recommendations and commands are included throughout.

Security attacks have become more advanced; therefore, security solutions have needed to evolve to deal with those threats. Cisco's acquisition of Sourcefire brings a new paradigm to the security landscape. No longer is security a one-time, instantaneous event. Security now is threat based, network cognizant, and continuous. All organizations, public and private, need to be aware not only of the constantly changing threat environment, but must be prepared to respond in kind.

Cisco Collaboration Systems Release (CSR) 10.6, along with CUCM 10.5(2), enhances the user and administrator experiences and interactions. In many cases, a change to one product may necessitate changes to other products. For example, where the deployment options for video conference control changed to place all control behind the Telepresence Conductor, Cisco Prime Collaboration management tools had to be updated to reflect this new deployment approach. As new endpoints are added, CUCM and Prime Collaboration both needed to be updated to reflect the new endpoints.

Despite advances in security, hackers continue to break through network defenses. In this hour-long webinar, network security specialist Catherine Paquet will examine the favorite methods and targets of hackers and will introduce you to the different categories of security technologies. In this foundational presentation, you will learn about the benefits of security solutions such as firewalls, VPNs, IPS, identity services and BYOD.

Cisco Internetwork Operating System (IOS) has been around since a little after the inception of Cisco Systems as a company. In 1984, Len and Sandy Bosack from Stanford University founded Cisco Systems with a small commercial gateway server. The first Cisco router that I touched was an Advanced Gateway Server (AGS), which was the first marketed product of the company. After this came the Mid-Range Gateway Server (MGS), the Compact Gateway Server (CGS) and later the Integrated Gateway Server (IGS) and AGS+. The first version of IOS that I touched was 8.2(7). The operating system was based on a Unix-based system and was designed as a monolithic operating system, meaning that processes are stacked and interrelated.

Learn more about the many benefits of Global Knowledge's Virtual Classroom Live training.

In this second webinar in a series dedicated to building up network security, network security specialist Catherine Paquet will fill you in on advanced threat protection that integrates real-time contextual awareness, intelligent security automation and superior performance with industry-leading network intrusion prevention, Sourcefire.

Your clients, vendors and workforce don't always operate in the same building, state or country. Cisco Collaboration Endpoint products make communicating with your counterparts across town or on the other side of the world easy. This white paper provides you with product specifications and capabilities for Cisco's phone, desktop, and large screen immersive videoconferencing options.

The Cisco Unified Collaboration solutions offer anytime, anywhere access for organizations who need instant access to clients, vendors and remote employees. Cisco products enable authorized external users to connect to corporate resources, create different user groups and manage large scale deployments. Learn how Cisco Unified Collaboration infrastructure products can help you provide everything from call control which provides signaling and dial plan support to the expressway series providing firewall traversal for external access.

The responsibility for securing organizational data has spread beyond the traditional IT professional. While there are more diverse security solutions, there are more diverse and sophisticated security threats. Security awareness and training is essential for everyone within an organization. Learn how Cisco has continued to evolve its security solutions and training.

What path you decide to take to earn your Cisco Certified Network Associate (CCNA) Routing and Switching certification will depend on a number of factors including your availability, willingness to work long hours and your ability to absorb a lot of information in a short period of time. This white paper includes self-assessments and training recommendations to help you figure out if taking the CCNAX Routing and Switching Boot Camp or taking two separate ICND1 and ICND2 courses is the best fit for you.

Learn how Cisco FabricPath combines the benefits of Layer 2 Switching and Layer 3 Routing, allowing for the scalability and flexibility of Layer 2 while supporting traditional Layer 3 components such as optimal paths, equal cost multipath routing and a Time to Live (TTL) field.

Which mainstay certifications should be in your list of credentials? What's the next up-and-coming certification? This article will help you answer both questions by providing a review of the 15 top-paying certifications.

This hour-long, information-packed webinar will provide tips and tricks for modifying and optimizing router path selection with EIGRP and OSPF. You will learn about EIGRP redistribution, including redistributing static routes into EIGRP, and about OSPF redistribution. You'll learn about using route maps and prefix lists and about summarization with EIGRP and OSPF. Also, you will receive tips for controlling updates and path selection.

What were the top paying IT and project management certifications for 2016? his article will help you answer both questions by providing a review of the 15 top-paying certifications.

Understand the two training options to prepare for the CCNA Routing and Switching certification - traditional and accelerated. Global Knowledge allows you to learn at your pace. The traditional training path features two courses, ICND1 and ICND2, and ten days of training. The accelerated training path combines the content found in ICND1 and ICND2 into a single 5 day course, the CCNAX Routing and Switching Boot Camp. Learn which option is best for you.