The OSI Reference Model
No real world network operating systems conform exactly to the OSI model, but it is useful as a reference when describing existing systems. It is difficult to study network devices such as routers, switches, and gateways without using the model. 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 ...
Network Operating Systems
The purpose of a network is to permit users share resources located on other computers and to share peripheral devices such as printers. A network operating system (NOS) is specialized systems software designed to provide networking functionality. More ...
WAN Network Protocols - DSL, SONET, HDLC, DWDM, DLSW+
This article discusses some of the most implemented Wide Area Networking (WAN) protocols in enterprise networking environments today including HDLC, DSL, SONET, DWDM, and DLSW+. HDLC is a Cisco proprietary protocol for designed for sending data across serial links. 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 ...
Internet Security and VPN Network Design
This article discusses some essential technical concepts associated with a VPN. A Virtual Private Network (VPN) integrates remote employees, company offices, and business partners using the Internet and secures encrypted tunnels between locations. More ...
Remote Control Protocols
Remote control protocols like Remote Desktop Protocol (RDP), Secure Shell (SSH), and Citrix Independent Computing Architecture (ICA), allow a system to access another system and transfer the user interface, keystrokes, and mouse movements between syatems as if you were actually sitting at the other syatem. 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 ...
IPv6 Packet Fragmentation
Unlike in IPv4, an IPv6 router does not fragment a packet unless it is the source of the packet. The fields used in the IPv4 header for fragmentation do not exist in the IPv6 header. More ...
Networking Protocols, Ports, Standards, and Organizations What Does it All Mean?
A protocol is a set of rules that devices agree to. A port is specific electronic connection, or software interface a protocol uses. A standard is a specification that the characteristics of the protocol's signal and the design of the interface. Networking standards are developed by networking standards organizations. More ...
IPv6 Multicast Addresses
An IPv6 multicast address defines a group of devices known as a multicast group. Unlike IPv4, there is no broadcast address in IPv6. Instead, IPv6 uses multicast. A packet sent to a multicast group always has a unicast source address. More ...
IEEE 802.11 Wireless Modulation Methods
IEEE 802.11 Wireless Modulation Methods 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 ...
Looking at the OSI 7 Layer Reference Model
The OSI (Open Systems Interconnection) model is a 7 layer reference model for how applications can communicate over a network. Don't confuse The OSI model with TCP/IP Protocol which has 4 layers and is the actual architecture used for networking. More ...
A Simple Description of the IPv6 Header and Datagram
This article provides a simple description of the IPv6 header and datagram without a lot referring back to IPv4. More ...
