Virtual Local Area Networks (VLANs)
A Virtual LAN (VLAN) is a subgroup within a local network. VLANs make it easy for network administrators to separate a single switched network into subnetworks to match the functional and security requirements of their network without having to make major changes in the existing network infrastructure. More ...
Free eBook: Introduction to 802.11 Wireless
The growth of wireless mobile devices is incredible. If you're an IT professional you'll need to understand wireless technology. This free ebook by Aaron Balchunas explains everything from radio frequency to wireless authentication protocols. More ...
Introducing OpenStack
OpenStack is one of the most popular cloud computing management packages. OpenStack provides a common platform for controlling clouds of servers, storage, network, and even application resources. OpenStack is managed through a web-based interface, a command-line interface (CLI), and an application programming interface (API). More ...
What's the Difference Between a Packet and a Frame?
When speaking of the data in a network, people often call everything a packet. A more proper generic term would be protocol data unit or PDU. The specific name for a PDU depends on at what layer the data unit is in the OSI model. More ...
Network Routing Protocols - IGRP, EIGRP, OSPF, ISIS, BGP
The purpose of routing protocols is to learn of available routes on the network and make routing decisions. There are two primary routing protocol types; link state and distance vector. Some of the most common routing protocols include RIP, IGRP, EIGRP, OSPF, IS-IS and BGP. More ...
IPv6 Dynamic Address Allocation
As with IPv4, IPv6 addresses can be statically assigned. However, when it comes to dynamic addressing, IPv6 has a different approach. IPv6 uses the ICMPv6 Router Advertisement message to suggest to devices how to obtain their IPv6 addressing information. More ...
What is PPP, PPPoA and PPPoE?
PPP was designed to provide a connection between two devices. PPP comes with options including encryption, authentication and data compression. PPPoA is the standard for connection over an ADSL network. PPPoE is the standard for connection over an Ethernet network. More ...
The OSI Application Layer
This layer provides the interface between applications and the Network Operating System (NOS). The Application layer provides network services and applications such as HTTP, FTP, TELNET and SMP. More ...
Link Aggregation
If all ports on a switch are operating at the same speed, the ports most likely to experience congestion are ports connecting to another switch or router. To help alleviate congested links between switches, you can logically combine multiple physical connections into a single logical connection. More ...
IPv4 Datagram Fields
If you are pursuing CompTIA Network+ certification, of if you're involved in network troubleshooting, it's important to understand the construction of an IP datagram. More ...
TCP Windowing
It would be inefficient to return an ACK message as each segment is received. The number of segments received before an ACK message is returned is called the TCP receive window size. More ...
Network Cabling and Components
Although the power and sophistication of networking protocols and software is impressive, a network could not operate without physical cable and components. Even a wireless network needs physical components such as access points. More ...
The OSI Session Layer
The Session layer, layer seven of the OSI model, establishes, synchronizes, maintains and terminates sessions between computers on a network. It establishes a connection ID and authenticates security. More ...
Comparing IPv4 and IPv6 at a Glance
When examining the details of the IPv4 and IPv6 headers, there are some important differences between the two protocols. This article summarizes some of the differences. More ...
T-Carrier - A Complete and Comprehensive Guide
T-carrier was introduced in 1962 by AT&T Bell Laboratories. A T1 line has the capacity of transmitting 1.544 Mbps and it can also be used to send 24 digitized voice channels. Dispite its age, because of its reliability, T-carrier is the most commonly used digital transmission service in the US, Canada, and Japan. More ...
