Understanding the Components of a Home Network by Jeff Heaton
Home networks are becoming more common. People want to be able to share a single broadband Internet connection to several computers in the house. There are many different devices that you can use to make up your home network. If you have never heard network terminology device names like router,... What is a Hub A hub is a device that has several Ethernet ports on the back of the device. ... To connect a switch to a router simply connect the switch’s "uplink" port to one of the routers Ethernet ports.

Cisco CCNA Certification: An Illustrated Guide To Ethernet CSMA/CD by Chris Bryant
When you're studying for your CCNA exams, you're going to study the theory of technologies we basically take for granted in networking. CSMA/CD is one of those technologies. It works beautifully and you don't even have to configure it. But to be an effective network troubleshooter (and to pass... The sole physical components were the Ethernet cards in the computers and coaxial cable. ... This jam signal indicates to all other devices on the Ethernet segment that there has been a collision, and they should not send data onto the wire.

Vlans by Kashif Raza
In order to implement VLANs in a network environment, you'll need a Layer 2 switch that supports them. Almost all switches sold today that are described as "managed" switches provide the ability to make ports members of different VLANs. However, switches that don't provide any configuration... If a switch includes Layer 3 capabilities, it can be configured to route traffic between VLANs defined in the switch, without the need for packets to ever leave the switch. ... One of the issues with VLAN tagging is that by adding information to an Ethernet frame, the size of the frame can move...

Cisco CCNA Exam Tutorial: Defining Collision Domains by Chris Bryant
CCNA exam success depends on mastering the fundamentals, and two important fundamentals are knowing exactly what the terms "collision domain" and "broadcast domain" mean. In this free Cisco tutorial, we'll take a look at the term "collision domain" and how a collision domain is defined. ... We could connect each host into a separate port on a hub (a hub is basically a multiport repeater) and we'd still have one single collision domain with four hosts in it. ... If we connect each of these four hosts to their own separate switch port, we would now have four separate collision domains, each...

Network+ Certification Exam Tutorial: Ethernet CSMA/CD Explained by Chris Bryant
When you're studying for the Network+ exam, you've got a lot of new acronyms to learn! One of the basics is CSMA/CD, which stands for Carrier Sense Multiple Access with Collision Detection. That's quite a mouthful, but it's an important term to know for both your exam and real-world success. ... On an Ethernet segment, hosts can send data at any time. ... This jam signal tells the other hosts that there has been a collision and that they should not attempt to send data at this time. ... That's an effective technique, but the two hosts still have to send their data.

Penetration Testing on a Switched LAN by Brian Wilson
In this is article we will explore the presence of known vulnerabilities in switched LAN’s. I hope to open your eyes on some of the techniques & tools that can be freely downloaded and used to test your network. Let’s start out with some of the basics we see in most small to medium networks. ... To sniff on an Ethernet LAN you need to have access to the network via switch port of other network connection. ... Ethernet (CAT3, CAT5, or CAT6): To tap Ethernet it’s normally done by using a protocol sniffer like Ethereal.

Synchronised Digital Clock Systems by David Evans
Synchronised digital clocks allow a number of individual time clock displays to show identical accurate time. Individual stand-alone digital clocks each drift at different rates eventually all display differing times. This article discusses the methods utilised to achieve synchronised digital... Ethernet NTP Digital Clock Systems Ethernet NTP digital wall clock time displays utilise NTP over Ethernet to display a continuously accurate synchronised time. ... The devices are powered over standard CAT5 cabling using Power-over-Ethernet (IEEE 802.af), the same Ethernet standard as...

iSCSI vs. FC for Meeting Mission Critical Requirements by Efrat Aharoni-Levi
Introduction Mission Critical Data is just what its name says: critical to the core functioning of an enterprise. Mission critical data must be available 24x7 and fully backed up for immediate recovery in the event of disaster. Enterprises are constantly seeking more reliable, more efficient,... SANRAD’s V-Switch 3000 provides a single integrated hardware/software solution to SAN management: • Infrastructure: The V-Switch 3000 uses an enterprise’s existing IP infrastructure including existing Ethernet switches, cabling, GBICs and SFPs.

Server Racks by Josh Riverside
A "rack" is designed to hold items, and it is usually on a two-post or four-post frame. So a server rack is a frame that contains server components. The new server racks are designed to hold the servers and also to cool them and other electronic equipment by allowing air to flow in a... Modern designs provide accommodations for keyboard, video, mouse switches, Ethernet hubs, etc. ... Some primary advantages of server racks are improving cabling management, providing superior physical security, and easy hardware maintenance.

Cisco Certification: The Definitive Guide To ARP, IARP, RARP, and Proxy ARP by Chris Bryant
When I first started studying for my CCNA years ago, one of the (many) things that confused me was ARP. Or rather, what ARP did as opposed to Reverse ARP, Inverse ARP, and Proxy ARP! One book would mention ARP without mentioning the other variations, one would mention RARP but not Proxy ARP, and... A repeater's job is simply to regenerate a signal to make it stronger, and a hub is simply a multiport repeater. ... Since Ethernet is a broadcast media, every other device on the segment will see it.