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 ...
Wireless Standards - 802.11a 802.11b 802.11g 802.11n 802.11i Explained
The IEEE 802.11 family of standards which provides for Wireless Ethernet or (Wi-Fi) has evolved over the years. This article explains the differences between 802.11a 802.11b 802.11g 802.11n and 802.11i. More ...
Internet Protocol versions IPv4, IPv5 and IPv6
Internet Protocol is the part of the TCP/IP protocol that is responsible for addressing packets. IPv4 uses a 32-bit address IPv6 uses a 128-bit address. This article describes how IPv4 are converted to IPv6 addresses. 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 ...
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 ...
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 ...
X.25 and Frame Relay Overview
Frame Relay originated as an extension of integrated services digital network (ISDN). Its designers aimed to enable a packet-switched network to transport over circuit-switched technology. The technology has become a stand-alone and cost-effective means of creating a WAN. More ...
Active Directory : How Objects Are Stored and Identified
Data stored in Active Directory is presented to the user in a hierarchical fashion. There are two types of objects: containers and non-containers. The most common type of container in Active Directory is an OU (Organizational Unit). Non-container objects are also known as leaf nodes. 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 ...
IPv6 Unicast Addresses
The 3 categories of IPv6 addresses are:Unicast identifies a single interface. A packet sent to a unicast address is delivered to the interface identified by that address. Multicast identifies a group of interfaces. A packet sent to a multicast address is delivered to all interfaces identified by that address. Anycast identifies a group of interfaces. A packet sent to an anycast address is delivered to the closest member of a group. More ...
IPv6 Neighbor Discovery Protocol (NDP)
Neighbor Discovery Protocol (NDP) is used by IPv6 hosts for Router Discovery, Neighbor Discovery and Duplicate Address Discovery. 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 ...
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 ...
VTP (VLAN Trunking Protocol)
A VLAN (Virtual LAN) allows a network administrator to partition a LAN to conform to the business functions of the organization without physically modifying the network. VTP (VLAN Trunking Protocol) is a Cisco proprietary protocol that allows an administrator to configure VLANs on a single VTP server, easing the administration of a network. 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 ...
