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 ...
IPv6 Prefix Length Notation
In IPv4, the prefix (or network portion) of the address can be identified by a dotted-decimal netmask, commonly referred to as a subnet mask. IPv6 address prefixes can be represented much the same way that IPv4 address prefixes are written in CIDR notation. More ...
Understanding IP Routing
The Transmission Control Protocol/Internet Protocol TCP/IP suite of protocols is the underlying technology for information exchange on the Internet. This essential reference shows you how to isolate and resolve common network failures and to sustain optimal network operation. More ...
T-Carrier
T-carrier is a time-division multiplexed (TDM) digital signal that has been used by the telephone companies for many decades. 24 8-bit signals are time-division multiplexed into a 1.544 Mbps t-carrier signal. More ...
NTP Server Systems - The Network Time Protocol
The Network Time Protocol (NTP) is utilized by NTP Server systems to distribute accurate time information to network time clients. The NTP protocol is widely used throughout the Internet to provide synchronization of computers and processes. This article discusses how NTP server systems utilize the Network Time Protocol to provide networks with an accurate reference of time. 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 ...
IPv6 Anycast Addresses
An IPv6 anycast address can be assigned to more than one interface. In other words, multiple devices can have the same anycast address. A packet sent to an anycast address is routed to the nearest interface having that address, according to the routers routing table. More ...
DSL (Digital Subscriber Line)
DSL (Digital Subscriber Line) is a technology used to transmit digital data over telephone lines. DSL service can be transmitted simultaneously with voice band telephone service on the same line because DSL uses a much higher frequency that rides on top of the low 3400 Hz voiceband. 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 ...
TCP/IP Utilities
TCP/IP comes with a set of command line utilities that a network technician can use to manage and troubleshoot a network. PING is used to test the ability of two hosts on a network to communicate. More ...
How to Set Up FTP (File Transfer Protocol)
FTP (File Transfer Protocol) is used to transfer computer files between a client and server on a network. This article explains how to set up FTP on IIS and that FTP is not a secure protocol and some secure file transfer alternatives. More ...
SYN-ACK Handshake to Establish a TCP Connection
TCP uses a SYN-ACK handshake to establish a connection. Three messages are required to establish a TCP connection between two hosts. More ...
Network Gateways
When networks with different protocols, such as Ethernet and Token Ring need to be connected together, this requires reconstruction of the data packets. To do this, information from above the network layer is required. A gateway is a device that can function at all seven layers of the OSI model. More ...
Video - Data Link Layer of OSI Networking Model
In this video by Kevin Wallace you learn about the Data Link Layer of the OSI networking model. 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 ...
