Resource Library

Welcome back! Previously, we decided that in order for a Layer-3 MPLS VPN to function correctly, the ingress PE is going to need to push two labels onto each data packet. Let’s say that we have a data packet going from site A2 to site A3, using the topology shown in...

Private networks are under constant threat of attack, even when steps have been taken to "secure" them. The large volume of malicious codes, and their ability to evolve and adapt, requires security professionals and common computer/internet users alike to be mindful of their actions and constantly play defense. This white paper focuses on 10 common ways that malicious code can penetrate a network. Knowledge of these methods and the ability to recognize them are the first steps in preventing them from succeeding in harming your network.

Windows Vista introduced AERO, a desktop experience that had four major elements; Windows Flip, Windows Filmstrip, AERO Glass transparency and fully realized thumbnail views on the Taskbar. Windows 7 added several new features to AERO, including AERO Snap, AERO Shake...

I recently came across an opportunity to use a relatively new feature in Cisco Unified Communications Manager (CUCM). Suppose you are the telecom administrator at a community hospital. During business hours, the Facilities Department is staffed and team members simpl...

Windows Software Update Services (WSUS) is commonly used to distribute security patches and updates for Windows operating systems and Microsoft applications. WSUS is a web application that runs within Internet Information Services (IIS) on Windows Server. When client...

Adding a new computer to an Active Directory domain can be a disruptive process, particularly if that computer is part of a large, high-speed deployment. Djoin.exe is a command line tool that permits the joining of a Windows 7 or Server 2008 R2 computer to Active Dir...

As is sometimes the case, the idea for this article originated with a student question I received during one of the Securing Networks with ASA Fundamentals classes I have taught this summer. The course material mentions a simple scenario whereby IP Telephony traffic...

Ever seen a /32 prefix in the IP routing table? A /32 prefix is commonly referred to as a host route since it identifies a route to a specific IP host address. Since most (but not all) host computers don't run routing protocols, we could create a host route on a rou...

As is frequently the case these days, I get a brainstorm for an article during a Cisco Security training class I conduct. This summer I taught the Securing Networks with ASA Fundamentals class, which concentrates heavily on the Adaptive Security Device Manager (ASDM)...

Organizations can find significant value in adopting Agile methodologies and techniques. Agile practices can help ensure you meet customer expectations, deliver products on time, and create a motivated environment that is able to quickly adapt to change. This white paper explores 12 benefits of Agile development and management, explaining why you should consider incorporating Agile methodologies into your current standards and processes.

Need to know the difference between copper and optical fiber? Want to learn what the acronyms PBX, PC, PCI, PCIe, PCM, PDA, and PDU mean? Our "Geek Speak v3.0" can teach you all this and more. An update to our popular v2.0 "Geek Speak", this white paper will teach you more than 925 popular IT words, phrases, and acronyms.

Negotiation is a dialogue intended to resolve disputes, to produce an agreement on courses of action, to bargain for individual or collective advantage, or to craft outcomes to satisfy various interests. It is the primary method of alternative dispute resolution. This white paper focuses primarily on the negotiation process, different negotiation styles, and the various elements of communication that affect the outcome, including: Negotiation Communications, Constructive Questioning, Communication Obstacles (and overcoming those obstacles), Challenging Negotiation Situations and "Traps," and, finally, completing Successful Negotiations, a.k.a. "Getting to Yes"

“Traceroute” is a utility that’s commonly used when troubleshooting IP networks, but many network managers at the CCNA level and beyond aren’t really sure how it works or what you can do with it. One reason for this might be that, unlike most things in the IP world, there are no standards documents describing how “Traceroute” functions. Thus the implementations are vendor-specific, and not even the utilities’ names are standardized. With Cisco IOS and Unix, it’s called “traceroute”, in the Microsoft world, it’s “tracert”, and other operating systems have similar utilities, such as “tracepath” for Linux.

In this webinar, the first of two based on our Cybersecurity Foundations course, you will examine the following topics: verifying users and what they can access, ways a user can be validated to computer and network resources, how cryptography is used to protect data, symmetric and asymmetric encryption and hashes.

Interior Gateway Routing Protocol (IGRP) was a Cisco-proprietary Distance-Vector (D-V) classful routing protocol - basically an improved version of RIPv1. Like other D-V protocols, each IGRP router periodically flooded its routing table, but it differed from RIP in two ways. First, RIP’s advertisement interval was thirty seconds but IGRP’s was ninety seconds, which allowed IGRP to scale to larger networks than RIP. Second, RIP used a simple hop count metric, but IGRP’s more sophisticated metric was based on minimum path bandwidth and total path delay, with options to include link reliability and interface loading.

In this webinar, the second of two based on our Cybersecurity Foundations course, you'll build on what you learned in the first of the series, Protecting Your Network with Authentication and Cryptography.

One command that had a fairly long history first with the PIX Firewall and now the ASA is the shun command. In this post we’ll examine this command’s history, why it’s useful, and its new-found resurgence in threat detection implementation.

In this webinar, you will examine the need for IPv6 and whether it's possible to survive on IPv6 alone. You will learn ways to phase in IPv6 and how to successfully migrate to IPv6.

I attended a meeting this week with a customer of mine and a potential new vendor. The new vendor was there to pitch his configuration and setup service offerings for a specific ITSM toolset. My customer has already had one bad experience with an ITSM tool configuration vendor who promised one thing and delivered much less. He ended up with a tool that’s minimally used and not configured to match his business needs. He’s looking for a vendor that can understand his business needs and priorities and quickly help him get his tool configured and working in a short time frame. Then the topic of standard changes came up. My customer asked for examples of standard changes. The vendor responded, “Server reboots are an example of standard changes.”

Planning for a cyber disaster makes recovering from one much easier. Still, as important as disaster planning is, it's often overlooked or put off until it is too late. In this webinar, Global Knowledge instructor Debbie Dahlin discusses planning for the unexpected -- whether the unexpected means a simple power outage, a network security breach, or a major natural disaster. She'll discuss risk analysis and risk management techniques and explain the importance and process of creating a business continuity plan. Using a fictional company as an example, Debbie will walk you through the disaster planning process a security professional should use, and she will provide simple tricks to reduce your company's downtime before, during, and after a disaster.

This week’s post highlights some of the features and implementation specifics regarding the Datagram Transport Layer Service (DTLS) protocol used in Virtual Private Networks with the Cisco AnyConnect^® SSL client. I’ll provide some background as well as some screenshots and supported CLI commands.

In the fourth of his five-part series, Eric Strause explores the hardware and application benefits inherent in a cloud-based architecture.

According to the OSI layer concept, routing, or best path selection, takes place on Layer 3 and is based on the logical address. In this post, we want to discuss some of the points in that statement.

Global Knowledge Course Director and Lab Topology Architect Joey DeWiele, a specialist in Unified Communications, explains the difference between our Cisco Unified Communications courses - ACUCW1 & ACUCW2.

In this informative, hour-long webinar, Global Knowledge instructor Debbie Dahlin will explore an abundance of important cloud computing security issues. She will help you gain insight into the key cloud security issues of maintaining the confidentiality, integrity, and availability of corporate information and applications.

An attacker needs to destroy evidence of his presence and activities for several reasons like being able to maintain access and evade detection (and the resulting punishment). Erasing evidence of a compromise is a requirement for any attacker who wants to remain obscure and evade trace back. This usually starts with erasing the contaminated logins and any possible error messages that may have been generated from the attack process.

In this hour-long webinar, Global Knowledge instructor John Barnes will guide you through implementing Cisco private VLANs. He will review VLANs and 802.1q, and he will discuss private VLAN fundamentals and operation, covering primary VLANs and secondary VLANs. He will cover VLAN mapping and discuss using private VLANs between multiple switches. He will also provide a use case example.

Although the GSS can be configured to be authoritative for an entire domain, e.g. cisco.com (option 1), the GSS is designed to be integrated into an existing traditional BIND-based or any DNS system. The GSS operates as an A-record DNS server for Hosted Domains (HD) for which it has been delegated authority from a higher-level name server, which generally would be a name server (NS) controlled by an Enterprise or ISP. In addition to A-record support, the GSS is able to proxy for other query types using NS Forwarding and a back-end name server such as BIND.

In this hour-long webinar, security expert and Global Knowledge instructor Phillip D. Shade will provide insight into the emerging network security science of network forensics analysis, a.k.a. security event analysis and reconstruction. Using case studies, you will examine the role of data retention in network forensics analysis, and you will learn about applying forensics analysis techniques to handle application-based attacks, VoIP call interception, and worms, bots, and viruses.

In this post I’ll focus on a topic that’s mentioned in the Cisco FIREWALL training class but isn’t emphasized there or in the online Cisco ASA documentation. When configuring failover on a pair of ASA security appliances, a situation can arise in which network disruption occurs due to the secondary ASA in a failover pair becoming active first and then the primary comes online second. Both the documentation and the courseware point out that this causes the secondary (and active ASA) to swap its interface MAC addresses with those of the primary. Being naturally skeptical about this behavior, I decided to investigate. The rest of this post illustrates my confirmation of this phenomenon.

The official Cisco CCNP Security FIREWALL training course (as well as other documentation) recommends enabling the inspection of the Internet Control Message Protocol (ICMP), even though it’s disabled by default. The image below displays the recommended practice as configured in ASDM, but the curious student might wonder what the unchecked “ICMP Error” box is. That’s what I’ll focus on in this post.

This report discusses the growing significance of human capital and intellectual property on the performance, sustainability, and valuation of companies. It examines the business drivers for investing in the acquisition, development, and certification of knowledge workers as well as current technology and economic trends that are accentuating the critical need to invest in the education and training of employees and customers.

As long as I've been involved in service management, one of the perennial debates that's really never been resolved focuses around how many discrete processes ITIL describes. No such single list exists in the ITIL core books. However, section 4.1 of each of the ITIL 2011 core books shows the processes described within that specific book. When we deliver accredited ITIL training, if it is describe in section 4.1 of any of the ITIL core books, then it is considered a "process".

Your business has been hacked, leaving you with a persistent bot; now what? In this hour-long webinar, security expert David Willson will discuss ways you can eliminate the threat in an act of self-defense or defense of property. As new laws are explored, old ones amended, and solutions sought, you'll take a look at thinking outside the box to give the good guys the advantage-or at least a fighting chance.

The Cisco UCS is truly a “unified” architecture that integrates three major datacenter technologies into a single, coherent system: Computing Network Storage Instead of being simply the next generation of blade servers, the Cisco UCS is an innova­tive architecture designed from scratch to be highly scalable, efficient, and powerful with one-third less infrastructure than traditional blade servers.

Previously, I talked about the logical and physical steps to building a basic certification lab, concentrating mostly on the CCENT/CCNA Routing and Switching level. Once you have that set of certifications under your belt, there are several options for specialization. Each of these advanced technology tracks serve as methods of enhancing your professional skill set as follows:

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).

Configuring a wireless lab for study and testing capabilities is a bit more involved than you might think at first glance. Most of the requirements take place on the management devices, but the underlying switch infrastructure requires some preparations as well. The tasks involved are as follows:

Good question! There are lots of networks, so I’m sorry to say that it depends. Let me explain. The smallest computer-based networks are usually PANs or Personal Area Networks. They can connect a wireless keyboard, mouse, or other devices to a computer. You may find them wirelessly linking a printer to your computer. You may have noticed these all include wireless connections. A PAN most often uses wireless technologies like infrared and Bluetooth, so it is really a WPAN (Wireless Personal Area Network).

Examine fifteen common myths surrounding virtualization, including many that prevent IT administrators (or their bosses) from getting the maximum value from virtualization. This paper is designed to be vendor-neutral; in other words, the basic concepts and advantages are the same whether you choose to use Citrix XenServer, VMware vSphere, Microsoft Hyper-V, or one of the many Linux-based solutions. We'll break the reasons into three broad categories (Cost/ROI, Performance, and Other), allowing you to focus in on a specific area if desired, or you can review the entire white paper for a broader view.