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Learning how to program and develop for the Hadoop platform can lead to lucrative new career opportunities in Big Data. But like the problems it solves, the Hadoop framework can be quite complex and challenging. Join Global Knowledge instructor and Technology Consultant Rich Morrow as he leads you through some of the hurdles and pitfalls students encounter on the Hadoop learning path. Building a strong foundation, leveraging online resources, and focusing on the basics with professional training can help neophytes across the Hadoop finish line.

So what makes a new certification "Hot"? Is it the perceived qualitative value? Or is it the possible increase in salary? Is it just the fact that so many are seeking that one particular certification? How about the governing body of the certification? Or maybe it is a combination of one or more of these? Whatever the case, there are new certifications (and some that have been completely re-written as to be a new certification) that are perceived to be the "ones" to possess and will be highly desirable in 2013.

As with the adoption of any new technology, the move from IP version 4 to IP version 6 will take a number of years to complete. During that transition phase, various mechanisms will be necessary to continue support of the older protocol as the newer gains widespread momentum. In addition, there has been some evolution even within the availability of these mechanisms, some of which have already passed from general use into deprecated status. Network engineering professionals already proficient in the use of IPv6, as well as the available coexistence mechanisms, will undoubtedly stay in high demand throughout this process.

Risk is something we deal with on a daily basis. Living in New Jersey and having the occasional storm, I’ve recently performed my own risk assessment determining the value of certain assets and activities and made a decision on what I was willing to spend to reduce risk to what I perceived as an acceptable level. My management of risk was a rather simple case. Sure, in my revised business continuity plan for my home, I’ll make sure that I have more D cell batteries, have my garage door adjusted so it opens manually again, more food I can heat on a stove and that doesn’t rely on refrigeration, and finally I’ll consider a whole house gas generator that uses natural gas, which has always been available to power critical systems like the sump pump in my basement. What if, however, I was a really large business? One with lots of components and interdependencies that require a tight integration in order to succeed? How and where can a large volume of information necessary to management, business continuity, and disaster recovery be correlated and communicated to those individuals who, because of their roles and responsibilities, need to make the critical decisions regarding the management of risk?

The STP (Spanning Tree Protocol) standard (IEEE 802.1d) was designed when the recovery after an outage could wait a minute or so and be acceptable performance. With Layer 3 switching in LANs, switching began to compete with routers running protocols because they are able to offer faster alternate paths. Rapid Spanning Tree Protocol (RSTP or IEEE 802.1w) brought the ability to take the twenty seconds of waiting for the Max Age counter plus fifteen seconds of Listening plus fifteen seconds of Learning or fifty seconds down to less than one second for point-to-point connected and edge switches and six seconds for root switches.

In a recent post, I gave an overall description of a service portfolio and the key components of a portfolio. Here, I will describe how a cloud services provider might implement an ITIL service portfolio. A cloud services provider will regularly have a set of services under development, a set of service in live operation, and a set of services that are retired.

ITIL describes a service portfolio as a collection of the overall set of services managed by a service provider. A service portfolio describes a service provider’s boundaries and promises across all of the customers and market spaces it serves. I like to think of a service portfolio as describing the past, present, and future collection of services offered by a service provider. The figure below shows a high-level view of a service portfolio.

This short example illustrates basic VLAN operation. Examining VLANs in a large-scale installation can show the full benefits of VLANs. Consider that this is a small portion of a large corporate headquarters with 5,000 devices connected in a 20 building campus.

In 1998, the Internet Engineering Task Force (IETF) released RFC 2460, outlining the technical specifications of IPv6, which addressed the shortcomings of the aging IPv4 protocol. As with any evolution of technology, new elements exist in the protocol that may seem strange and unfamiliar. This certainly includes address representation, space, and so forth, but also includes a number of different types of addresses as well. A subset of these new addressing types has corresponding types in IPv4, but many will seem significantly different. The purpose of this white paper is to examine addressing classifications in detail and outline their functions within the context of the protocol.

Regardless of your vendor preference or your experience on the Juniper JUNOS CLI, assuming you have a point of reference to another vendor, your first thought when experiencing JUNOS is, “I have been here before.” The CLI is familiar, convenient, and polished. The similarities between JUNOS CLI and another CLI such as Cisco’s IOS are not what I want to focus on here however; it is their differences I want to focus on. But first, when you connect to a JUNOS powered device and access Operational Mode (see Brad Wilson’s blog post Introduction to Juniper Junos), it looks very much like the User EXEC Mode in IOS. In fact, there are a lot of JUNOS commands that are very much like the IOS User EXEC Mode commands.

If you are upgrading to ESXi 5.1, there are some important facts that you should consider first. Upgrading involves many stages and processes that must be performed in a specific order. Many of these processes are one-way and do not provide a "back button." If you do not use care and consideration in your upgrade plan, you could possibly lose important data and configuration; and potentially even lose contact with your servers.

Depending on the switch vendor, the exact steps will vary on how to set up and configure VLANs on a switch. For the network design shown, the general process for setting up VLANs on the switch is:

We already covered the first three of the twelve advantages of Agile software development. These three advantages focus on team development and refining the process. Advantage #4: Motivated Development Team The positive relationship with a reasonable and satisfied customer is only one of the reasons why many developers prefer to work on Agile projects. The other main contributor is that they tend to value working in self directed teams (which the Agile methods require for success).

Self-awareness is a very powerful tool for leaders in every type of business or organization. The more leaders can maximize their self awareness the greater the impact on business performance, employee engagement and leadership and development initiatives. Self-awareness is the central component of personal development and emotional intelligence. For most leaders today it is still underdeveloped and frequently underemployed. Better understanding of this important leadership trait is critical for leadership and organizational success.

For several years, most news articles about a computer, network, or Internet-based compromise have mentioned the phrase "zero day exploit" or "zero day attack," but rarely do these articles define what this is. A zero day exploit is any attack that was previously unknown to the target or security experts in general. Many believe that the term refers to attacks that were just released into the wild or developed by hackers in the current calendar day. This is generally not the case. The "zero day" component of the term refers to the lack of prior knowledge about the attack, highlighting the idea that the victim has zero day's notice of an attack. The main feature of a zero day attack is that since it is an unknown attack, there are no specific defenses or filters for it. Thus, a wide number of targets are vulnerable to the exploit.

Now that the network is installed, each switch has a bridge ID number, and the root switch has been elected, the next step is for each switch to perform a calculation to determine the best link to the root switch. Each switch will do this by comparing the path cost for each link based on the speed. For paths that go through one or more other switches, the link costs are added. The switch compares this aggregate value to the other link costs to determine the best path to the root switch.

There is a reason why the Agile methods are becoming mainstream. They can work! Although every Agile practice is not necessarily appropriate for every organization, each practice has delivered real value to many organizations, and some Agile practices can be used by anyone! This four part series explores twelve ways in which the Agile methods are valuable. I’ll bet that you will find more than a few that could be valuable for you!

That depends on their configurations. For example: While it makes very good sense to include redundant physical links in a network, connecting switches in loops, without taking the appropriate measures, will cause havoc on a network. Without the correct measures, a switch floods broadcast frames out all of its ports, causing serious problems for the network devices. The main problem is a broadcast storm where broadcast frames are flooded through every switch until all available bandwidth is used and all network devices have more inbound frames than they can process.

Some of you might just be starting out as a database administrator and need to know what a basic Transact-SQL query is for Microsoft SQL Server 2012, others might already be creating database objects. Either way, we put together a list of a few terms regarding Microsoft SQL Server that any database administrator should know.

I recently responded to a message on LinkedIn from a regular reader of this blog. He asked several questions which I will answer over the course of several posts. As part of his first question, he described a strategy report that his group is producing. The audience for this strategy report considers ITIL important to the future of their business, and so he must describe which ITIL processes his data center operations group works most closely with.

As we discussed previously, Cisco created the Nexus Operating System (NX-OS) to power its next-generation data-center switching platform. While this new OS shares many similarities to the original IOS, there are some definite differences that you need to be aware of as you begin using it.

Knowledge Management examines how we acquire, organize, manage, share, and utilize knowledge and information. The Internet gives us an overwhelming amount of information on a daily basis — and the volume of information available is growing rapidly! One of the biggest challenges for individuals and organizations involved in project management is to make the best use of this knowledge and information so they can operate more efficiently, improve decision making, and sustain a competitive advantage.

The most obvious difference is that hubs operate at Layer 1 of the OSI model while bridges and switches work with MAC addresses at Layer 2 of the OSI model. Hubs are really just multi-port repeaters. They ignore the content of an Ethernet frame and simply resend every frame they receive out every interface on the hub. The challenge is that the Ethernet frames will show up at every device attached to a hub instead of just the intended destination (a security gap), and inbound frames often collide with outbound frames (a performance issue).

In the last two posts I discussed aspects of services in the context of some landscaping work that I’m having done. This is clearly what many people would call a “non-IT example.” I often use similar examples in my classes. However, I might initially describe an example that seems unrelated to IT, but will conclude with a challenge to students. That challenge is, “identify the IT in this example.” The truth of the matter is that most businesses these days are underpinned by some form of information technology. In fact, technology has become so ingrained into everyday services that often even the service providers themselves don’t realize how technology supports their business.

Lessons learned is a theory, or conclusion, based on evidence at a given time and describes what went wrong (as well as what went right) throughout the lifecycle of a project. Although it’s completed during the project closeout process, it should occur during the entire project lifecycle to ensure all information is captured and documented. Consequences of not having a project review of lessons learned are the increased likelihood of repeating actions that might have caused:

Previously I discussed service providers and their risks in the example of my involvement with a landscaping company. ITIL clearly states that services, “…deliver value to customers by facilitating outcomes customers want to achieve…” However, sometimes organizations and people focus on outputs as opposed to outcomes, which sacrifices some of the value of the service. This leads to a question, what is the difference between an outcome and an output?

Global Knowledge Course Director and Lab Topology Architect Joey DeWiele, a specialist in Unified Communications, explains the difference between Cisco's Call Manager Express & Call Manager.

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.

As mentioned in last week’s post, interviews that require ITIL Intermediate level knowledge will most likely be targeted to specific process areas and activities. If I interviewed someone for a job that required ITIL Intermediate level knowledge, in addition to other questions about the specific technical responsibilities of the job, I might ask the following questions:

“Twisted Pair” is another way to identify a network cabling solution that’s also called Unshielded Twisted Pair (UTP) and was invented by Alexander Graham Bell in 1881. Indoor business telephone applications use them in 25-pair bundles. In homes, they were down to four wires, but in networking we use them in 8-wire cables. By twisting the pairs at different rates (twists per foot), cable manufacturers can reduce the electromagnetic pulses coming from the cable while improving the cable’s ability to reject common electronic noise from the environment.

Global Knowledge practice director for cloud solutions, Hank Marquis, explains the people, process, and technology aspects of cloud computing.

Both technologies, Ethernet and FC, satisfied the two conditions at that time, but there was a catch. Read more. 

Here are seven tips for working with vSphere, including: Logging in via Command Line, dealing with connection problems using ssh to an ESXi host; network performance issues; possible storage problems; Log Files to View in vSphere ESXi 5; network performance troubleshooting; migrating to a virtual machine using VMotion.

Everyone has been involved in a learning program or project that has not delivered its intended impact. Across organizations, remarkably similar but preventable missteps are made in needs identification, learning strategies, program development and implementation.  Instructor Tom Gram, Senior Director of Professional Services at Global Knowledge, will present six classic mistakes learning professionals make that reduce chances for success along with evidence-based practices to help prevent them. 

Network security is everyone's concern, and this applies to computer security as well. Many security breaches occur due to user ignorance of basic security principles, not malicious intent. Network and computer security are like an onion - there are multiple layers. Good security begins with understanding what you can do to keep your systems safe and implementing a layered approach. If you depend on one program or feature to secure your computer, then when (not if, but when) that dependency is breached, you may have personal information stolen or even have your computer taken over.

None of us have much time to waste, so what can you do when your environment changes quickly and you need to come up to speed on a device that you have never seen before? You find the quickest way to bring yourself up to speed. Some of you will have experience with other vendors’ equipment, and some of you will not have much experience at all; therefore, we will focus on topics that will get your feet wet the quickest and have you talking Junos in no time.

What's the correct sequence of activities for handling an incident? Find out why categorization occurs before initial diagnosis in the ITIL incident management process flow so you can answer this common ITIL Foundation exam question.

IT departments have multiple opportunities and challenges as a result of the Bring Your Own Device (BYOD) invasion. The most common opportunity is to reinforce enterprise network security from both the inside and the outside. Supporting BYOD also offers more monitoring and tracking of activities that provide a more detailed view of network traffic flow. Alternatively, it will be a challenge for some IT departments to give up control over which devices may access their enterprise network. Another challenge will be to have the users doing configurations for network access, which adds human error to a crucial part of the process. The opportunities and challenges BYOD represents are real. Enterprises must make their network infrastructure BYOD ready to meet the onslaught.

During a recent ITIL foundation class, a student asked an interesting question. She wanted to know: “What is the difference between a project and a service?” To be honest, I haven’t spent much time thinking about this distinction. However, I think that those of us who practice ITIL consulting and training should have good answers to questions such as this. Here’s how I answered this question.

XenApp 6.5 brings a host of features and benefits that most companies will need as the technology continues to evolve and user requirements continue to expand.

The term "life cycle" implies two things: that a process is perpetual and that the sequence of events is obligatory or uni-directional. There is no beginning or end to a life cycle and the sequence of events cannot change. A seed cannot go directly to being a mature plant nor revert back to the blossom stage.

Here are some secrets, tips, and tricks for virtualizing your datacenter. We want to introduce some best practices for virtualization, while not being too biased towards one virtualization vendor or another. We'll use some common examples of products and tools that work with VMware's vSphere and Microsoft's Hyper-V, but with an eye toward virtualization in general, and not the specifics of any of the capable platforms that could be used). We will assume, however, that bare metal hypervisors, in other words virtualization platforms where the hyper visor is the OS, will be used as opposed to running a hypervisor on top of an existing general-purpose operating system (which is great in a lab, but terrible for data center projects).

These five "secrets" to virtualizing desktops will greatly increase the chance of a successfully VDI implementation. It is very important to plan for this; to balance the hardware environment to handle not just average but peak load; to properly size storage, not just for capacity, but for performance as well; to minimize the number of base images so that the costs of maintaining each can also be minimized; and to accept and embrace the fact that people will connect with a wide variety of devices, and to create a plan to accommodate as many of these devices as is feasible at the lowest cost.

In the previous post, we discussed the need for VXLAN in the cloud along with the issues it solves. In this post, we will focus more on how VXLAN works.

Global Knowledge Course Director and Lab Topology Architect Joey DeWiele, a specialist in Unified Communications, explains QoS.

The 'Go Further' video is an testimonial to the value of Microsoft Certification as a validation of technical skills. Whether you're just starting your IT career, or looking to advance it, certification can make a huge impact. Take a look at the video, and hear the stories of real MCPs.

In my last post I discussed aspects of problem management in the context of a real-life situation regarding the first vehicle I owned. In that scenario, and throughout this series of posts, I’ve demonstrated a real-life situation from a standpoint of the incident and problem management processes that ITIL describes.

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.

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).

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:

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).

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:

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.

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.

For us wireless folks that aren’t stellar routing and switching guys, one of the most daunting network tasks is integrating our WLAN infrastructure with the existing wired infrastructure and its services. Understanding wired design topics is pretty fundamental to installing or managing any network, so it really should be on our priority list to spruce up those skills. To give you a nudge on your journey, let’s talk about DHCP for wireless clients.

As many of you work on integrating Avaya Aura System and Session Manager into your networks, the case for troubleshooting will indeed occur. There are built in tests in the System Manager that allow you to run tests on 14 different areas, including Session Manager. But what do you do with the results when you get them? I am going to outline six of the most common problems and solutions when installing and implementing System and Session Manager and what steps you can take to troubleshoot and correct the problem.

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".

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.

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.

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.

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.

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.

The Global Site Selector (GSS) leverages the Domain Name System (DNS) to provide clients with reliable and efficient content services. Domain to IP address mapping is performed with consideration for availability, location, and load of content servers. Using the GSS in combination with Cisco’s Content Services Switch (CSS), Cisco’s Catalyst 6000 Content Switching Module (CSM), or Cisco’s Application Control Engine (ACE) allows users to create Global Server Load Balancing (GSLB) networks.

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.

Relational databases are important not only because of the information they store but, more importantly, for the data we retrieve from them. The select statement allows us to ask the database a question. It’s the way we retrieve information from the database system.

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 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.

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.

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.

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.

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

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.

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.

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.

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, 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.

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.

Dcdiag is an often overlooked tool that can discover problems in a domain controller’s configuration. If client computers can't locate a domain controller or if domain controllers can't replicate Active Directory, you can run tests with Dcdiag to look for a solution.

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.