The OSI Presentation Layer
At this layer applications communicate on a format for exchanging data. The Session layer provides character set conversion and formats the data. It performs encryption and decryption, compression and decompression. 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 ...
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 ...
Major Protocols in the TCP/IP Suite
This is a chart of the layers of the TCP/IP Suite and the major protocols in each layer. As you move your mouse pointer over each protocol acronym, a brief description of the protocol appears. This is not a comprehensive list. 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 ...
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 ...
IP Addressing
The IP protocol uses a 32-bit address to define the network segment address and the node address. If the device is to be connected to the Internet, the address needs to be unique among all other devices connected to the Internet. 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 ...
Session Border Controllers - More Than Just a Voice Firewall
The migration from Time-Division Multiplexing to the more flexible IP based SIP networks brought an unexpected security challenge. Session Border Controllers focused primarily on SIP and H.323 session security. 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 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 ...
Comparing IPv4 and IPv6 at a Glance
When examining the details of the IPv4 and IPv6 headers, there are some important differences between the two protocols. This article summarizes some of the differences. 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 ...
The TCP/IP protocol Datagram Format
A datagram is the packet format defined by the Internet Protocol. A pictorial representation of an IP datagram shows the first five or six 32-bit words of the datagram are control information called the header. More ...
IP Addressing and Subnetting
Today, many different kinds of devices can communicate on a network. A network device might be a computer, a router, a printer, or any number of unusual devices. Every device on a network that uses the Internet protocol (IP) needs a unique IP address. More ...
