PoE (Power Over Ethernet)
Say you want to mount a wireless access point (AP) on the ceiling. Although no electrical outlet is available, a switch feature called Power over Ethernet (PoE) IEEE 802.3at standard offers as much as 32.4W of power over a UTP cable. 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 ...
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 ...
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 ...
Video - Introducing the OSI Model
This video by Kevin Wallace introduces the OSI networking model. 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 ...
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 ...
Neighbor Discovery Protocol (NDP)
Neighbor Discovery Protocol is part of the new version of the Internet Protocol (IPv6). Its function is to resolve IPv6 addresses into valid MAC addresses. All addresses discovered by NDR are stored in a buffer known as the neighbor cache. More ...
Ports and Sockets
Data transmitted over the Internet carries a 32-bit IP address that identifies its destination computer and a 16-bit number that identifies a port on that computer. The combination of the IP address and the port number is called a socket. A pair of sockets, one on the sending computer and one on the receiving computer uniquely identifies a specific connection on the Internet. More ...
IPv4 Address Classes
Originally, IP network numbers were defined with rigid boundaries and grouped into address classes. Even though address classes was created to facilitate efficient use of the IPv4 address space, because of its rigidity it has been abandoned for more flexible classless addressing. More ...
IPv6 Payload Length Field and Jumbograms
The IPv6 Payload Length field is a 16-bit field that indicates the length in bytes of just the payload following the main IPv6 header, it does not include the main IPv6 header. If the IPv6 packet has one or more extension headers, they are included in the number of bytes contained in the Payload Length field. 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 ...
IPv6 Address Types and Scopes
An IPv6 addresses have a size of 128 bits have three types, unicast, multicast, and anycast. Unicast addresses are for a one-to-one communication. Multicast addresses are for a one-to-many communication. Anycast addresses are for one node to nearest node of multiple nodes communication. 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 ...
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 ...
