Video - Introducing the OSI Model
This video by Kevin Wallace introduces the OSI networking model. More ...
IEEE 802.11.x Wireless Standards
The 802.11 standard, approved in 1997, applies to wireless LANs with a 1 or 2 Mbps transmission rate in the 2.4 GHz band. Sometimes the term 802.11 is used to refer to the 802.11x family of specifications. More ...
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 ...
Dynamic Host Configuration Protocol (DHCP) Explained
In the early days of TCP/IP each device on a network had stored on its hard disk a configuration file that an administrator used to manually assign a static IP address. Today a network administrator is no longer required to maintain an IP and MAC address configuration file a server. Every device on a network is automatically assigned a unique IP address by Dynamic Host Configuration Protocol (DHCP). More ...
OSPF (Open Shortest Path First) Protocol
OSPF (Open Shortest Path First) protocol is a protocol that handles routing for IP traffic. Because it is based on an open standard, OSPF is very popular in many corporate networks today and has many advantages. 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 ...
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/IP Protocol Suite
A good portion of the knowledge required to be a network technician relates to the TCP/IP protocol suite. This article describes the most important protocols in the TCP/IP protocol suite. Many other less frequently used protocols exist. More ...
OSI Network Model
The OSI model was developed years ago as a reference for network protocol and application designers to build their products with an open standard. That would promote a standard for developing network devices, interfaces, applications and services that would work together. It is a model rather than a specification since it defines layers and services for those layers and how each layer works with the layer above and below it. More ...
IPv6 Global Unicast Addresses
Global unicast addresses (GUAs) are globally routable and reachable in the IPv6 Internet; they are equivalent to public IPv4 addresses. GUA addresses are also known as aggregatable global unicast addresses. More ...
Representation of IPv6 Addresses
IPv6 addresses are 128 bits in length and written as a string of hexadecimal digits. At first glance, these addresses can look overwhelming. RFC 2373 and RFC 5952 provide two helpful rules for reducing the notation involved in the standard format. More ...
Unicast, Multicast, Broadcast. What Does It Mean?
Unicast, Multicast, and Broadcast are different network transmission methods. Unicast is a transmission between a single sender and a single receiver, while Broadcast is a transmission from a single sender to all clients on the network. More ...
RADIUS Protocol
RADIUS (Remote Authentication Dial-In User Service) is an application layer protocol that provides centralized Authorization, Authentication, and Accounting management for users who connect and use a network service. More ...
The OSI Physical Layer
The Physical layer (OSI layer 1) deals with the mechanical and electrical specifications of the network hardware. Layer 1 specifications define connectors, pin-outs, signal voltages, and related software. More ...
Integration of IPv6 with IPv4
Almost all networks use IPv4. The question is how to move them over to IPv6 while allowing them to keep the networks they currently have operating. There are three methods. More ...
