Cisco Network Time Protocol Configuration

As discussed in the previous Network Time Protocol (NTP) concepts article, the configuration of NTP is not overly complex. The first thing that needs to be determined is the method of NTP operation that best fits the requirements for the target network; once this decision has been made, the steps shown in this article can be […]

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Understanding Cisco Network Time Protocol Concepts

One of the new topics that has (up to this point) not been covered on Cisco’s CCNA level exams has been the Network Time Protocol (NTP). Time synchronization is used within a network for two main purposes: to maintain very high accuracy synchronization between Time Division Multiplexing (TDM) nodes and to maintain clock time between […]

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Cisco IOS Image Security

This article discusses Cisco IOS image types and provides methods to ensure that the images are complete and have not been modified. It also briefly covers digital signatures that are possible with newer Cisco hardware. Overview The previous article talked about the different Cisco IOS image types, the image file-naming structure, and the different ways […]

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Cisco ASA Access Lists Concepts and Configuration

Sean Wilkins review Cisco’s Adaptive Security Appliance (ASA) implementation of access control lists (ACL or access list). He also covers ASA access list types, what they control, and a basic review of what the configuration syntax is to use them. Overview For those just getting into the network security arena or into Cisco network security […]

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Advanced IPv4 Concepts and Examples

This article includes a longer discussion of how subnetting is used to separate a larger address space into smaller pieces for more efficient assignment and routing. This will include a discussion of how to perform the binary math that is required for more complex subnetting. This article is a continuation of where “IP Subnetting Basics” […]

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