Tips

Tips

• OpenNMS, an introduction: Affordable network management

  Open source expert Maria Winslow brings network managers up to speed about the free open source enterprise-grade network-management system OpenNMS.  Continue Reading

• IEEE 802.3at: Power over Ethernet plus

  802.3af Power over Ethernet (PoE) has been widely adopted for powering VoIP phones, wireless access points and a number of other network-connected products. But it provides a limited amount of power. In this tip, David Jacobs investigates the latest...  Continue Reading

• VPNs: Fundamentals and basics

  VPNs are discussed in this introductory tip on the fundamentals of virtual private networks.  Continue Reading

• Content Delivery Networking: an introduction

  Doug Downer gives an overview of Content Delivery Network (CDN) technology and its components, which bring together the functionality of file access, caching, multimedia delivery and application processing.  Continue Reading

• Configuring and troubleshooting wireless LAN clients

  An understanding of wireless LAN (WLAN) client and WLAN access point communication mechanisms is critical to anyone attempting to initially connect or troubleshoot a WLAN connection. In this tip, Robbie Harrell discusses some of the issues that can ...  Continue Reading

• Securing your Layer 2 network: Don't overlook the basics

  Before dropping substantial cash on a fancy surveillance system, most sensible home owners would ensure that their doors and windows were locked. Similarly, there are simple security measures you can take to configure your systems for Layer 2 ...  Continue Reading

• Understanding network traffic flow analysis

  Network traffic flow is often compared to highway traffic flow. In this tip, Lindi Horton shows parallels between those two worlds and explains why traffic flow analysis is such an essential piece of knowledge for engineering a network.  Continue Reading

• Using Snort, Nessus and Tripwire for network security

  Why pay a proprietary vendor a ton of money for a security application you can get for little or no money? In this tip, learn the pros and cons of open source network security tools Snort, Nessus and Tripwire.  Continue Reading

• IP network design, part 4: LAN design

  This final section of the IP network design series relates to the issues encountered with campus LAN design. The benefits of Ethernet switching over a traditional hub environment are first explained. The motivation behind the deployment of virtual ...  Continue Reading

• Certifications that will earn you the most money

  Ed Tittel takes a look at the five network certifications that earned the most money in 2005.  Continue Reading

• IP network design, part 3: Designing the WAN

  The wide area network (WAN) is the single biggest contributor to a corporate network's cost of ownership. Therefore, this is the area where the cost-versus-performance tradeoff is most pronounced and most critical. This article explores the various ...  Continue Reading

• Implementing software restriction policies

  This tip explains how you can use software restriction policies to keep your workstations in pristine shape and cut down on help desk calls at the same time.  Continue Reading

• Router Expert: Initial configuration of a Cisco 1200 802.11g WLAN access point

  Our router expert continues his series on building a secure wireless LAN with a Linux base. This article explains how to utilize a single Cisco 1200 series access point to provide access to three different IP network segments using VLANs and ...  Continue Reading

• LAN connectivity problem: Blame DNS, NIC or firewall?

  ITKnowledge Exchange member "BinooDas1234" had connectivity issues with a troublesome LAN, and fellow techies jumped in to help out. But does the answer lie in the DNS configuration, the NIC drivers or elsewhere? Here is a portion of the ...  Continue Reading

• IP network design, part 2: The IP addressing plan

  The IP addressing plan is the foundation upon which a successful logical design is built. Part two of this tip explains how to formulate a scalable IP addressing plan that can support the network as it grows.  Continue Reading

• IP network design, part 1: Fundamental principles

  A competent network design is the foundation upon which all successful network implementations are built. This is the first of four articles that focus on the design of IP-based networks, due to the prevalence of IP as the de-facto standard desktop ...  Continue Reading

• OSI: Securing the Stack, Layer 5 -- session hijacking

  To help secure your systems against session hijacking, this tip walks you through the steps hackers use to hijack active sessions and take over your network. You'll also learn how to detect and prevent session hijacking attacks, a major security ...  Continue Reading

• Making sense of Windows routing tables

  When routing packets across a network, things do occasionally go wrong. In these situations, it is helpful to be familiar with the Windows routing tables. Routing tables dictate the flow of packets from the machine in question. This tip will show ...  Continue Reading

• Network security checklist

  While 100% security is hardly a possibility, there are several things that you can do to make your network more secure. Learn about them with this network security checklist.  Continue Reading

• VRFs and routing

  Doug Downer continues his series about VPN routing and forwarding instances focused on the task of configuring and verifying a VRF scenario with a requirement for separate customers on a shared device. In this tip, he shows how to configure a method...  Continue Reading

• Router numbers

  Many of the routing protocols implemented in Cisco's IOS require a number to follow the command that enables the routing protocol in question. If you're new to routing, these numbers can be a little confusing, as they mean something different to ...  Continue Reading

• Wireless LAN security: 802.11i

  What is 802.11i, and is it really practical for you to implement in your organization? Robbie Harrell explores how the new wireless standard can improve security -- and reasons why you may want to switch to 802.11i or stick with WPA.  Continue Reading

• Router Expert: Building VLAN interfaces in Linux and IOS

  Segmenting a wireless LAN with VLANs can increase security. Find out from our router expert how to support VLAN interfaces in Linux and Cisco IOS.  Continue Reading

• Cache poisoning attacks and how to prevent them

  Want something scary to think about? A compromise of your name servers could cut you off from the Internet or redirect your customers to a competitor. It could even shunt sensitive electronic mail through an intermediate mail server or reroute your ...  Continue Reading

• VPN security: Where are the vulnerabilities?

  SOX compliance mandates have pushed organizations to deliver end-to-end VPN security. This means that the VPN itself is no longer enough. Robbie Harrell explains how organizations can apply security policies to the VPN in this tip.  Continue Reading

• Router Expert: Building 802.11Q VLANs

  Network segmentation can be a great way to increase security. This article covers segmenting with VLANs and the 802.1Q standard.  Continue Reading

• Understanding the differences between IDS and IPS

  We all know that the Internet is a haven for cyber criminals who use the connectivity to launch an unprecedented number of attacks against enterprise networks. IDS and IPS have been developed to combat these threats, but they are not one in the same...  Continue Reading

• Keeping it all separate with VRFs

  A Virtual Routing and Forwarding (VRF) instance can deliver separation across both a shared infrastructure and shared devices, ultimately simplifying management.  Continue Reading

• The network administrator's guide to forensic first response

  The time between discovery of an incident and the handover of digital evidence is critical for the possibility of successful evidence retrieval. Mishandled evidence, whether to be used in court or solely in house, can damage the integrity of the ...  Continue Reading

• Hardening your router in 9 easy steps

  For most enterprise LANs, the router has become one of the most critical security appliances in use. Configured properly, it can keep all but the most determined bad guys out, and if you want, it can even keep the good guys in. But an improperly ...  Continue Reading

• Router Expert: Standard interface configuration for a WLAN proxy server

  Our router expert continues his series on building a secure WLAN with a Linux base. This article covers standard interface configuration of the http proxy server.  Continue Reading

• Troubleshooting Windows VPN servers

  There are several aspects of the Windows remote access server that can create issues when a VPN client connects. This article focuses on some common trouble spots on the server side and offers steps to help pinpoint the problem.  Continue Reading

• Wireless LAN deployment and federal regulations

  A look at the bare minimum requirements to keep your WLAN compliant with federal regulations.  Continue Reading

• Secure WLAN best practices and topology

  Expert Michael Martin provides a list of wireless security "dos and don'ts" and a sample topology for a secure WLAN.  Continue Reading

• Seven steps to ensure project success

  The Value Manager recently had a project fall well below expectations. He reviewed what happened and came up with seven key steps for managing technical risk and one golden rule.  Continue Reading

• Router Expert: Filtering with MAC addresses

  This month our router expert discuss some strategies for controlling host network access using MAC address filtering.  Continue Reading

• Focus Windows port scanning with the netscan command

  How to use the netscan command to focus Windows port scanning.  Continue Reading

• Network administrator security policies

  Some security policy elements that are specific to network administrators.  Continue Reading

• Minimizing Layer 2 problems

  Understanding the fundamentals of Spanning Tree Protocol.  Continue Reading

• Auto-MDIX

  How Auto-MDIX can solve the cross-over cable conundrum.  Continue Reading

• MPLS: Experimental bits and QoS

  MPLS experimental bits are used to provide QoS capabilities by utilizing the bits set in the MPLS labels.  Continue Reading

• VPLS, a new Layer 2 MPLS VPN technology

  A new Layer 2 MPLS VPN technology that provides similar reliablity and QoS as MPLS VPN, but in a more simplified way. But beware, it does have it's limitations.  Continue Reading

• Protocols, Lesson 7: Subnet masks and their effect

  Understand the different effects a subnet mask can have.  Continue Reading

• Protocols, Lesson 9: Subnet routing and communications

  Lesson 9 in our protocol series covers the communications side of subnetting.  Continue Reading

• MPLS - Preparing an RFP (Dos and Don'ts)

  A look at the things to include in an RFP, a request for proposal for VPN service.  Continue Reading

• Preventing Layer 2 security threats

  Layer 2 switched environments, typically found in enterprise customer wiring closets, can be easy targets for network security attacks.  Continue Reading

• Run your VoIP calls over a VPN for enhanced security

  A look at using a VPN to enhance VoIP security.  Continue Reading

• Top 10 'show' commands

  A list of the top ten 'show' commands.  Continue Reading

• MPLS - Label Switched Paths

  A look at some of the details of working with Label Switched Paths (LSPs).  Continue Reading

• Top 10 things to know about network administration

  A list of the most important things network administrators should know.  Continue Reading

• Router Expert: Understanding reverse telnet and IOS terminal lines

  Learn how users interact with the terminal server and its connected devices through the use of reverse telnet, line and group rotaries, and terminal line interfaces.  Continue Reading

• Deploying both a private and public WLAN

  Lisa Phifer answers a reader's request for information about planning and deploying a wireless LAN -- one private and one public.  Continue Reading

• Monitor your traffic with MRTG

  The Multi Router Traffic Grapher is a free tool that can help you monitor the traffic on your network. Learn more here.  Continue Reading

• WLAN implementation tutorial -- Capacity planning: Step 1

  For WLAN implementation, make sure you have Step 1 down -- capacity planning, not just coverage.  Continue Reading

• The Network Life Cycle

  Each phase of the NLC has its own requirements that can typically be met with a judicious selection of tools and assessment solutions.  Continue Reading

• Router Expert: Implementing router interface redundancy

  While redundancy is simple as a concept, it becomes quite problematic in practice. This tip offers the basic options for router interface redundancy.  Continue Reading

• OSPF configuration

  Nuances of OSPF configuration could impact your network more than you expect.  Continue Reading

• Learning Guide: Voice over IP basics

  This guide contains all the VoIP basics and essentials you will need when implementing an IP telephony network.  Continue Reading

• Layer 3 MPLS VPNs

  A look at some of the details of Layer 3 MPLS VPNs.  Continue Reading

• Router Expert: Cisco asynchronous serial support

  Cisco IOS-based routers support three asynchronous serial interface types: Console, Auxiliary, and asynchronous port modules. This tip compares them.  Continue Reading

• Tips on working with VLSM

  Variable Length Subnet Masks (VLSM) can require some serious number crunching but there are many ways to help make the process simpler.  Continue Reading

• MPLS Versus IPSEC VPNs: Which one is right for you

  An examination of the similarities and differences between IPSEC and MPLS and some insight as to when one should be used over the other.  Continue Reading

• WLAN security: Beyond the VPN

  Wired networks have used virtual private networks (VPNs) to secure transactions across this edge, but this approach has its limitations.  Continue Reading

• WLAN security checklist

  WLAN security checklist  Continue Reading

• Should you use a voice VLAN

  Advantages and disadvantages of using a voice VLAN.  Continue Reading

• The VPN Expert: VPN client alternatives, part 4 -- IPsec

  Here's a list of IPsec clients that run on many systems. See what they have to offer and what they are often missing.  Continue Reading

• LAN addressing

  LAN addressing  Continue Reading

• Wireless LAN requirements

  Thinking of going wireless? Find out what you need to consider in planning for a wireless network.  Continue Reading

• The importance of the subnet mask

   Continue Reading