The Data Link Layer provides error detection and error recovery of the data flowing across the physical network link. The Specifications in this OSI Layer define network and protocol characteristics such as Physical addressing, network topology, error notification, flow control etc. The physical addressing defined in this layer determines how devices are addressed on the […]
[Continue reading]OSI Layer 1: Physical Layer
The Physical Layer defines the Electrical, Mechanical, and functional specifications of the physical link used to connect the communication device on the network. This layer defines characteristics like voltage levels, data rates, maximum transmission distances, connectors etc. The specifications in this Layer can be categorized as LAN or WAN:
[Continue reading]Home Network Setup – Wireless Home Network
The wireless home network technology is dominated by the WiFi brand (WiFi=Wireless Fidelity) which is based on the IEEE 802.11 standard. There exist different versions of the 802.11 standard (a,b,g,n) with different characteristics, as shown on this Post. A typical WiFi wireless home network is shown below:
[Continue reading]Home Network Setup – Firewire Network (IEEE 1394)
You can connect two computers together (back-to-back network) using the firewire port (IEEE 1394) found in almost all modern computers today. The firewire port has a data speed of 400Mbps, so you can have a high speed data connection to transfer files between the two computers. All you need is just a firewire cable (max. […]
[Continue reading]Home Network Setup – PowerLine Home Network (Homeplug)
PowerLine networking is based on the concept of “no new wires”, similar with the PhoneLine network technology. Basically it uses the existing electrical wiring in your house to create a home network. The PowerLine technology is driven by the HomePlug Industry Alliance, which defined the following standards: HomePlug 1.0 — Older Specification for connecting devices […]
[Continue reading]Home Network Setup – PhoneLine Network (HomePNA)
An excerpt from the HomePNA Alliance site (www.homepna.org) gives an excellent description of what a PhoneLine HPNA network is: “The HomePNA™ Alliance develops triple-play home networking solutions for distributing entertainment data over both existing coax cable and phone lines… By providing data rates up to 320 Mbps with guaranteed Quality of Service (QoS), HomePNA technology […]
[Continue reading]Home Network Setup – Ethernet Home Network
If you need a lot of speed in your wired home network, then Ethernet Technology is the way to go. An Ethernet network runs at data transfer speeds of 10/100/1000 Mbps (Mbps= Megabits Per Second), depending on the speed of the Network Interface Cards (NIC) used on the networked equipment. A speed of 100Mbps is […]
[Continue reading]Defense in Depth Security (or Defense in Layers)
This security approach is based on the concept of building several layers of defense around the host or information resource that you want to protect against malicious attacks. In enterprise IT networks, the defense in depth approach is implemented using different security infrastructure equipment and mechanisms. These include hardware firewalls, Intrusion Prevention Systems, Authentication and […]
[Continue reading]How To Protect your network from IP Spoofing
In a normal IP communication between two hosts, the sending host inserts its configured IP address in the ‘source IP’ field of the IP header, in order for the receiving host to know where to send the reply traffic back. In IP Spoofing, a malicious host can forge the IP header and change the source […]
[Continue reading]Most Common Networking Terms and Acronyms – C
CA Certification authority. Entity that issues digital certificates (especially X.509 certificates) and vouches for the binding between the data items in a certificate. CA certificate [Digital] certificate for one CA issued by another CA. Call-back a mechanism to place a call to a pre-defined or proposed location (and address) after receiving valid ID parameters. CAR […]
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