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To understand the difference between Ethernet II and 802.3, you first must know how Ethernet works. While Ethernet cables transmit data, their role is relatively simple compared to that of the Ethernet card — also referred to as an adapter. It’s within the function of this card that you find the differences between Ethernet II and 802.3.
Look back at the some of the highest paying IT certifications of 2020.
Most Internet users don't realize that often a website or other service that seems slow to respond is actually working fine. Instead, it’s the resolution of DNS that is putting a glitch in your giddy up. Fortunately, there are several steps you can take to optimize your DNS to get better performance.
Every second of every day, data is being sent and received. Billions of data packets are processed by your company’s network every day. In fact, you received dozens of packets just to read this article, but the vast majority of us have no idea how this works. People have no clue as to what goes on behind the scenes to ensure data actually gets to the right device.
Learn about the five types of area networks.
An quick fundamental overview of layer two devices. To learn more about this and similar topics, enroll in our exclusive Understanding Networking Fundamentals course.
The key difference between hubs, switches and bridges 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.
While Apple has created many fine things, they were yet to be created themselves when Xerox PARC scientists created Media Access Control addresses. These MAC addresses are 48 bits or 6 bytes long, so they are also known as MAC-48 or EUI-48. EUI stands for Extended Unique Identifier. It is written in hexadecimal characters as shown below:
This Certification Prep Guide provides an overview of the Microsoft Azure Fundamentals certification and offers helpful tips that you can use when preparing for your certification exam.
As IT departments struggle with skills gaps and businesses attempt to recovery economically from the COVID-19 pandemic, these 10 IT skills are essential to drive success. Job roles in these areas pay well, but decision-makers are struggling to find qualified candidates. If you’re looking to make an IT skills investment or start a new career path this year, these are the areas to consider.
While cybersecurity remains the most popular certification category in our IT Skills and Salary Report, foundational-level certifications highlight our list of the most popular IT certifications of 2020.
According to the Global Knowledge IT Skills and Salary Report, women make up 16% of the tech workforce, and an even smaller percentage (8%) are at the senior or executive level. Here’s an overview of the most popular and most pursued certifications by women in tech.
Global Knowledge subject matter experts predict the top trends for 2020 in IT training, Microsoft, Cisco, AWS, cybersecurity and more.
Looking ahead at new and emerging certifications provides insight into the areas deemed valuable in the IT industry. If you are an early adopter or in a position where you need to show that you have the bleeding-edge expertise of a technology, this list of recent and upcoming certifications is for you.
Using Palo Alto Networks, PAN-OS, enterprises can build an IT Security Platform capable of delivering protection against all stages of the Cyber-Attack Lifecycle. From Reconnaissance to Act on Objective, the PAN-OS Single-Pass Parallel Processing (SP3) engine combines efficient throughput with maximum data protection. This recorded webinar will describe how the SP3 Architecture can increase network traffic visibility and enable you to control your environment.
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 CCNAX - CCNA Routing and Switching Boot Camp is a great option to obtain Cisco Routing and Switching skills while pursuing the CCNA Routing and Switching certification.
Software-defined networking (SDN) is a solution that will enable your organization to meet the demands of network programmability and automation. The result will be greater network agility to support new applications while complying with increasing security needs.
The traditional network engineering model of configuring one device at a time simply doesn’t scale to the growing needs of today’s network. Cisco's intent-based networks and software-defined networking solutions will enable your organization to meet the demands of network programmability and automation. The result will be greater network agility to support new applications while complying with increasing security needs.
In the digital age, people and intellectual property have supplanted physical assets as the most important criteria for determining the value of an organization. It is the employees who develop the next big product or improve the practices, processes, services and internal culture that add significant value to an organization.
The process of subnetting is both a mathematical process and a network design process. Mathematics drives how subnets are calculated, identified, and assigned. The network design and requirements of the organization drive how many subnets are needed and how many hosts an individual subnet needs to support. Binary basics and IPv4 address structure were covered in part one of this two-part paper.
Google Cloud Platform (GCP) is Google’s public cloud offering comparable to Amazon Web Services and Microsoft Azure. The difference is that GCP is built upon Google's massive, cutting-edge infrastructure that handles the traffic and workload of all Google users. There is a wide range of services available in GCP ranging from Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS) to completely managed Software-as-a-Service (SaaS). We will discuss the available infrastructure components and how they provide a powerful and flexible foundation on which to build your applications.
Data center return on investment – which is measured by time to cost savings, time to revenue, time to break even, etc. – has proven more elusive than expected. But that doesn’t mean it isn’t attainable. To understand the genesis of the bad and ugly parts of data center ROI, we need to recognize the good parts and appreciate why so many companies are putting their faith in new and unfamiliar technologies.
In 2013, Cisco released their Software Defined Networking (SDN) solution for the data center known as Cisco Application Centric Infrastructure (ACI). For many years, the networking industry has been asking for an approach to configuring networking devices more efficiently than having to individually configure each and every router and switch.
This paper is a high level, moderately technical understanding of Hyper-Converged Infrastructures. IT managers, data center architects, and administrators alike may find this information helpful in their pursuit to simplify the data center and improve application performance.
The benefits of a RADIUS server are many. In addition to speed, you receive heightened security with user access monitoring, reporting and tracking functions and personalized restrictions. Setting it up costs less than $60 and this white paper walks you through each of the steps, settings, configurations and the equipment you will need.
Business processes are complicated, and mapping them is not a trivial task. Modelling standards give us the tools to model complex processes, but they do not tell us the best way to approach a model or effectively use the tool. In this hour-long webinar, Global Knowledge instructor Rod Fage will guide you through the best way to develop a model, from determining the goal and scope of the process and measuring its effectiveness, to modelling the process in a hierarchical top-down approach, enabling business analyst to continuously validate the model.
CompTIA has raised the bar for Network+ candidates. The new certification exam has significant changes to the five "domains" or knowledge areas with new content related to security, cloud, data-center and operational concerns and troubleshooting. There is also a greater emphasis on wireless networking and VoIP. Use this white paper to help you gain an overview of what's new and what's different.
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.
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.
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.
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.
A range of factors can influence the data center you choose. You should consider all of the factors listed in this white paper before deciding where to place your servers.
Accessing cloud-based resources, whether they be IaaS/PaaS/SaaS-based, is very convenient. With a browser and Internet connection, you are up and running. No driving to your work office, no need to log into the corporate network. Just open up your web browser and go. This convenience, however, comes with a security risk. All of your business work is conducted over an insecure communication network. Unlike your office network, where the network link between you and the data center is under corporate control and is physically secure, the cloud access link is over the Internet.
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).
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).
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.
Discover how Network Functions Virtualization (NFV) will revolutionize IT and change the way you think about network connectivity and perhaps even application development. This white paper is written for networking professionals but it may offer valuable insight for those in cross-functional roles such as DevOps, server virtualization, and data center management.
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.
Often, we don't have time to learn the reasons behind the standards we use. But learning what instigated a standard goes a long way toward not only understanding its importance, but also more easily and effectively applying it in your workplace. In this hour-long webinar, Global Knowledge instructor Keith Sorn will discuss common networking standards and explain how they were determined and why they are relevant. He will fill you in on things like why it's important to use proper color-coding standards when making cable and why the length limitations on wired cable are essential. He will also explain new standards, such as power over fiber.
Network Functions Virtualization (NFV) is gaining momentum along with Software-Defined Networking (SDN). This paper examines the history of NFV and explores the prospects for networking to gradually evolve from a hardware-centric approach to a software-driven model. It concludes with an examination of future market implications and how NFV can help organizations to achieve their goals.
After a review of Software-Defined Networking (SDN) and its close cousin Network Functions Virtualization (NFV), this white paper addresses three main deployment scenarios: SDN without deploying cloud computing, cloud computing without deploying SDN, and deploying cloud computing in conjunction with SDN. We'll look at use cases, when the approach makes sense, and any applicable limitations.
Instructor Carol Kavalla talks about the advantages of taking a Cisco Data Center Unified Fabric Implementation class from Global Knowledge.
Organizations are moving strongly toward Bring Your Own Device (BYOD) access, bringing outsourced activities back in-house, and finding ways to make use of the growing amounts of data flowing in from many new sources such as social media. These factors create an increasing shift in required and desired skills showing up in IT departments. Hiring and salary surveys, such as the 2014 IT Skills and Salary Survey from Global Knowledge and Windows IP Pro, TEKsystems' 2014 Annual IT Forecast, Foote Research Group's 2014 IT Skills and Certifications Pay Index, Computerworld's annual Forecast survey, Robert Half Technology Survey, and information from the US Bureau of Labor Statistics, Futurestep, Mondo, GovLoop, and Dice have presented a developing picture of the IT skills that will be in demand in 2014. Here, in survey order, are the top 10 major skills and why they made the list.
Instructor John Harmon explains subnetting using binary numbers and decimal conversions.
Instructor John Harmon continues his explanation of subnetting by showing how subnet masks can be used to sub-divide networks.
There are several Wireless LAN Standards, including b, g, and n, which exist in the 2.4 GHz band. These standards need around 20 MHz of radio frequency in order to transmit their signals. In this video, Ben Miller discusses how to pick access points and channels for optimal performance.
Answer? When it is flagged as a retransmission in Wireshark!
The driver behind 802.11n is MIMO, or multiple input multiple output. This video explains how MIMO works to double your channel speed by sending two or more data streams over the same channel.
Are you at a crossroads professionally or looking to start training for a new job? If so, you might want to consider pursuing network administration as a career. Network administrators are responsible for maintaining computer hardware and software systems that make up a computer network, including maintaining and monitoring active data networks, converged infrastructure networks, and related network equipment.
Global Knowledge Product Manager Tori Easterly discusses the benefits of our Understanding Networking Fundamentals course.
Multiplexing is the technology that is able to combine multiple communication signals together in order for them to traverse an otherwise single signal communication medium simultaneously. Multiplexing can be applied to both analog and digital signals. A benefit of using multiplexing, or muxing, is reducing the physical hardware cost for expensive dedicated network communication segments, such as copper or fiber cables.
Session Initiation Protocol (SIP) is an internet signaling protocol, developed by the IETF (starting in 1996), for establishing, maintaining, and tearing down sessions between a variety of real-time media, including voice, video, and chat. SIP allows endpoints to locate other endpoints, whether stationary or mobile. SIP doesn't have to worry about transporting voice or video as Real Time Transport Protocol (RTP) takes care of that. It also relies on Session Description Protocol (SDP) to negotiate capabilities and codecs. SIP does not provide a Directory Service or Authentication, but it does work with services such as LDAP or RADIUS. SIP is only concerned with signaling. This white paper is going to look at the way SIP is used in the converged Unified Communications environment.
A local area network (LAN) provides a path of communication, allowing the delivery of packets of data, voice, or video originating from the sender (logical source address) to the receiver (logical destination address). Ethernet is the most common LAN used. As you start to learn about networking, remember that communication and the movement of large numbers, whether it is people, cars, mail, or network traffic, have a commonality. Everything you know and use in your daily life can be compared to the way traffic moves.
The OSI model is a conceptual tool used to discuss and describe network functions. The use of a standard reference model is essential to communicating ideas as well as creating new technologies. It is a good idea to be familiar with the OSI model, the features assigned to each layer, and examples of common protocols or technologies associated with the OSI layers.
The OSI model is a conceptual tool used to discuss and describe network functions. The use of a standard reference model is essential to communicate ideas as well as create new technologies. It is a good idea to be familiar with the OSI model, the features assigned to each layer, and examples of common protocols or technologies associated with the OSI layers.
Diane Teare, Global Knowledge's Cisco Course Director, discusses the advantages to taking our CCNA Boot Camp.
One of the many useful features of tunneling is to carry non-IP traffic across an IP network, and this is still the case when dealing with IPv6 traffic. This transition mechanism makes use of a configured tunnel to transport IPv6 over a native IPv4 network, which may consist of two sites or more. Unlike the previous transition mechanisms, tunneling is not monolithic; while the basic principles may be similar, the operations are different. The following chart gives a breakdown of the current, major tunneling types in use, particularly in a Cisco environment:
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.
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.
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.
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:
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.
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.
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.
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).
“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.
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).
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).
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).
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.
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.
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 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.
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.”
No matter which IT field you're working in, there are several skills that are useful for every IT professional to know. Here, seven experienced IT professionals working in the networking, programming, project management, and security fields, share what they believe a...
Subnetting is a complicated topic that has confused students for a very long time. However, subnetting is an important topic for many different certifications with various vendors, including Cisco. In the real world environment, people are used to just punching in the numbers in many of the free subnet calculators that are readily available on the internet. For exam purposes, you still have to do this in a very fast manner since many exams are time-based and you don't have the luxury of spending those precious minutes on any single question. This Cisco training whitepaper will solve some of those age-old and complicated subnetting puzzles.