Post Views: 1,163 That’s right! ARIN formally announced today that IPv4 Adresses are gone – gone – gone in North America: That means that everyone is down to whatever they have. It also means that if your organization is not prepped to convert to IPv6 with a solid plan, it ought to be! Plus you […]
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Post Views: 1,677 OSPF (Open Shortest Path First) is an IGP (internal gateway protocol), and OSPF is an open standard protocol originally defined in RFC 2328. Since then OSPF has been updated numerous times including functionality to support IPv6 and Address Families. OSPF is supported on every major routing platform as well as Windows Server
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Post Views: 1,283 IP mobility is software and hardware designed to provide network access as a user travels from network to network. Cisco calls this the ubiquitous connection. Cellular telephone networks already accomplish this: You can begin a cellular call in Los Angeles, CA and (in theory) you should be able to drive to New
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Post Views: 5,686 For those of you who love Wireshark and are needing to analyze DNS Queries and Responses, we have the profile for you. Profiles are one of the most important Wireshark capabilities. Setting up and using different profiles for different environments, protocols, and tasks is a crucial skill that we teach in our
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Post Views: 1,375 A common question folks ask is “How do you check the bandwidth utilization on a router?” It is a great question and the answer is not as easy as you would expect. There are tools that accomplish this (i.e. NetFlow and there is another mentioned at the end of this page). However,
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Post Views: 982 The Border Gateway Protocol (BGP) allows internal and external networks or autonomous systems (AS’s) to exchange routes. BGP is a path-vector routing protocol, which simply means that its job is to exchange routing information between autonomous systems to find the most efficient path for your data to the Internet. Each BGP router
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Post Views: 1,615 In my prior article on getting started with nmap, I showed you how to get started with this superb network scanner. In that article we did basic scans to locate what hosts were on a given network and display what services were running on those hosts. In this article I am going
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Post Views: 1,143 In the prior articles (Getting Started with nmap and Deeper Scanning with nmap), we showed you how to get started, and how to dive deeper with this superb network scanner. Let’s go even deeper! One of the cool things nmap has is the ability to create scripts. Now doing this from
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Post Views: 2,314 Nmap (“Network Mapper”) is a free and open source (license) utility for network discovery and security auditing that has been around since 1997. Surveillance and network scanning is often one of the first steps in Penetration Testing or Security Validation. Many systems and network administrators also find it useful for tasks such
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Post Views: 1,758 Welcome to my little nmap cheat sheet! To learn more about nmap – check out my articles: Getting Started with nmap and Deeper Scanning with nmap and Even Deeper Scanning with nmap and Advanced nmap Scripting Engine. There was no intent here to recreate the full nmap capabilities, that would have been a waste
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Post Views: 931 We are often asked about ICMP, and how it should be managed on a network. We hope this How To will explain this protocol a little and provide some initial guidance. What is ICMP? The Internet Control Message Protocol (ICMP) is part of Layer 3, not Layer 4 TCP, and it’s not
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Post Views: 1,162 The Virtual Router Redundancy Protocol (VRRP) is a computer networking protocol that provides for automatic assignment of available Internet Protocol (IP) routers to participating hosts. This increases the availability and reliability of routing paths via automatic default gateway selections on an IP subnetwork. See RFC 5798. VRRP provides information on the state
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