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 ...
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 ...
IEEE 802 Standards Specify the Basics of Physical and Logical Networking
The (IEEE) Institute of Electrical and Electronics Engineers is an organization that defines standards for networking. The 802 Standards Specify the Basics of physical and logical networking. 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 ...
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 ...
Wireless Network Standards - 80211a, 80211b, 80211g, 80211n, 80216
This article describes the 80211a, 80211b, 80211g, 80211n, 80216, the current IEEE defined wireless protocol standards in use today, their bandwidth, maximum data rate, and coverage area. 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 ...
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 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 ...
Routing Datagrams
Systems can deliver packets only to other devices attached to the same physical network. A gateway is a network point, referred to as a router, that acts as an entrance to another network. 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 ...
The OSI Network Layer
The Network layer (OSI layer 3) uses routable protocols to deliver data packets to networks connected through routers. Routing is the process of moving data packets from one network or network segment to another. More ...
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 ...
IPv6 Dynamic Address Allocation
As with IPv4, IPv6 addresses can be statically assigned. However, when it comes to dynamic addressing, IPv6 has a different approach. IPv6 uses the ICMPv6 Router Advertisement message to suggest to devices how to obtain their IPv6 addressing information. 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 ...
