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 ...
IPv6 Address Format
IPv4 is running out of addresses. IPv6 was designed to solve this problem therefore it is important
to understand the format of an IPv6 address. More ...
What's the Difference Between a Packet and a Frame?
When speaking of the data in a network, people often call everything a packet. A more proper generic term would be protocol data unit or PDU. The specific name for a PDU depends on at what layer the data unit is in the OSI model. 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 ...
IPv6 Global Unicast Addresses
Global unicast addresses (GUAs) are globally routable and reachable in the IPv6 Internet; they are equivalent to public IPv4 addresses. GUA addresses are also known as aggregatable global unicast addresses. 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 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 ...
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 ...
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 ...
Video - Introducing the OSI Model
This video by Kevin Wallace introduces the OSI networking model. 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 ...
Network Switches
A bridge or router may be referred to as a switch because it uses information in the data packet to choose a path from one network segment to another. A bridge may be referred to as a layer 2 switch because it uses information from layer 2, the Data Link layer of the OSI model. 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 ...
Networking and Internet Standards Organizations
Without standards, the Internet would be chaos. The primary organization that sets communications standards for the Internet is the Internet Engineering Task Force (IETF). 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 ...
