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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.
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.
One of the most significant new features in Microsoft Windows Server 2012 is the Hyper-V Replica (HVR) capability. Whether you are considering this for your own organization or just prepping for your Windows Server 2012 MCSA, this white paper presents the essentials of deploying this disaster recovery feature.
Rodger Foster, our senior Cisco instructor, reviews how multiple gateways are used to provide redundancy in the network.
With Multiprotocol Label Switching (MPLS) as popular as it is in the provider space and private MPLS clouds for larger enterprise, we needed some tools to help troubleshoot and maintain these networks. With the providers in mind, the normal ping or traceroute may not be enough.
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.
One size does not always fit all. At times there’s a need to run more than one routing protocol and have more than one routing domain: multivendor shops, migration from one protocol to another, scalability issues of a single protocol, political or personal preference, production versus test networks, mergers, and acquisitions.
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 purpose of Interior Routing Protocols (IGP), and routing protocols more generally, is to advertise the existence of destination networks. All protocols then have some method of picking what they would consider to be the best path and maintain the information. By...
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:
Precision Time Protocol (PTP) is a protocol designed to go beyond what Network Time Protocol (NTP) can offer relative to accuracy. PTP is IEEE standard 1588 that can give local computing systems accuracy within the sub-microsecond range (such as microsecond, nanosecond or picoseconds) whereas NTP is within milliseconds or longer. PTP standard was first released in 2002 and known as 1588-2002. In 2008, the IEEE released a revised standard for PTP, known as 1588-2008, that improved the accuracy and precision of the protocol. It is also known as PTPv2 and is not backward compatible with the older version. PTP was developed for packet based network for control and measurement systems.
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.
Many companies are already using VoIP while incorporating video capabilities into their portfolio of services. One question that I am often asked is, “How can we ensure that the voice and video quality is good and consistent when using VoIP?”
Dynamic Multipoint Virtual Private Network (DMVPN) is a Cisco network solution for those with many sites that need access to either a hub site or to each other.
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.
Routers and switches make up the bulk of network infrastructure and are vulnerable to attack. We hear about mass Denial of Service (DOS) attacks or Distributed Denial of Service (DDOS), but the network itself is as big a risk because if it is taken out, there is no path for the data to flow.
This Webinar will focus on addressing the issues of an unsecure data center network and how to address the security concerns with Cisco ACI. The key components of how to create an ACI whitelist will be covered. View slide deck>>
This webinar will focus on addressing the issues of an unsecure campus network and how to address the insecurity with ISE. We then will look at how Cisco ISE can add security to devices beyond initial connectivity. View the slide deck>>
This webinar focuses on addressing the issues of an unsecure campus network and how to address the insecurity with 802.1X. We then will look at how Cisco ISE can centralize campus access with 802.1X. View the slide deck>>
The idea of building and running applications without thinking about the servers (AKA serverless computing) is a developers dream come true. Watch expert Rich Morrow to understand: The benefits of using serverless computing Different architectures that use serverless computing How AWS services, like Lambda, S3, API Gateway and DynamoDB work together to enable faster and more flexible application deployment and management. This video also features a live demo: Building a web app with only serverless components.
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.
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.
For organizations getting started with RHEL, Red Hat Training has developed a series of courses to develop the skills needed for basic administration and configuration of Red Hat Enterprise Linux. These courses introduce key command line concepts and enterprise-level tools, laying the foundation for the rapid deployment of Red Hat Enterprise Linux. The curriculum also introduces the basic administration skills needed for resolving configuration issues and integrating Red Hat Enterprise Linux systems with other existing environments. View the slide deck>>
Recently we've been comparing using Telnet with Secure Shell protocol to allow remote access to a device such as a router or switch. Now, we're going to compare File Transfer Protocol (FTP) and Trivial File Transfer protocol (TFTP) for a Cisco router or switch. These...
Frequently, questions come up in the Cisco Contact Center Express classes I teach concerning the ability of the system to perform this or that task. In this blog post, I will cover some of the more popular questions I get during class.
When you connect your server or storage, it will send a Fabric login (FLOGI) request. This FLOGI request serves two purposes: Fibre Channel ID is the WWPN connection to this port from the FLOGI server Exchange buffer credits with the switch To better understand the first function, it is exactly the same if I rewrite it as, “request an IP address for a MAC address from the DHCP server”.
Global Knowledge instructor Doug Notini discusses the benefits of our FIREWALL 2.0 - Deploying Cisco ASA Firewall Solutions course.
Both technologies, Ethernet and FC, satisfied the two conditions at that time, but there was a catch. Read more.
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.
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.
The Red Hat® Learning Subscription delivers 12-months of unlimited access to all Red Hat Online Training courses. The Standard RHLS subscription is a higher tier with access to 5 certification exams and up to 2 retakes.
In numerous Cisco classes, students learn about IPv4 and IPv6 address subnetting, complex subnetting, variable length subnet masking (VLSM), summarization, prefix routing, and address aggregation. These are valuable skills. In order to apply these skills efficiently, a network designer should possess one additional skill. Planning the IP address space for a Class A or B IPv4 address is necessary to apply the complex skills listed above properly. Complex subnetting, VLSM, and IP address summarization can be implemented simply and efficiently with proper planning.
Global Knowledge Course Director and Lab Topology Architect Joey DeWiele, a specialist in Unified Communications, explains QoS.
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.
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.
Course director Jim Thomas explains how our custom labs, which utilize external hosts, ISR routers, and DMZ, provide a real-world environment for students.
Cisco Unified Communications Manager (CUCM) includes a feature called "call throttling" that denies new call attempts when the system is in a state that may lead to delayed dial tone. The Real Time Monitoring Tool (RTMT) will generate a code yellow alert when call t...
In the spring of 2013, Cisco announced major updates to their Cisco Certified Network Associate (CCNA) curricula, including a new version of the CCNA Routing and Switching exam (200-120 CCNA). This paper provides a review of the CCNA Routing and Switching exam's critical concepts, as an aid to students preparing to pass the latest version of the CCNA Routing and Switching exam.
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).