Classless IP Addressing
In the beginning, classful addressing was a great idea for keeping IP addresses organized. But as the Internet grew, and IP addresses became scarce, classful addressing was found to be too limiting. Classless IP addressing, known as Inter-Domain Routing (CIDR) was released in September 1993. More ...
Network Cabling and Components
Although the power and sophistication of networking protocols and software is impressive, a network could not operate without physical cable and components. Even a wireless network needs physical components such as access points. 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 ...
DSL (Digital Subscriber Line)
DSL (Digital Subscriber Line) is a technology used to transmit digital data over telephone lines. DSL service can be transmitted simultaneously with voice band telephone service on the same line because DSL uses a much higher frequency that rides on top of the low 3400 Hz voiceband. 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 ...
IEEE 802.11 Wireless Modulation Methods
IEEE 802.11 Wireless Modulation Methods 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 ...
TCP Windowing
It would be inefficient to return an ACK message as each segment is received. The number of segments received before an ACK message is returned is called the TCP receive window size. 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 ...
IPv4 to IPv6 Transition With the Dual-Stack Technique
Transition from IPv4 to IPv6 has been slow. If you can't immediately convert all your network hardware to IPv6, the dual-stack technique allows the easiest operation of IPv4 and IPv6 devices on the same network. More ...
RIP (Routing Information Protocol)
RIP is an Interior Gateway Protocol (IGP) that uses hop count as a metric. RIP comes in versions 1, 2, and RIPng (RIP next generation) an extension of RIPv2 for support of IPv6. 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 ...
Looking at the OSI 7 Layer Reference Model
The OSI (Open Systems Interconnection) model is a 7 layer reference model for how applications can communicate over a network. Don't confuse The OSI model with TCP/IP Protocol which has 4 layers and is the actual architecture used for networking. More ...
What Are Private IP Addresses?
Normally you have to be assigned an IP address, or a group of IP addresses by a Regional Internet Registry. However, if you just need IP addresses for an internal network that will not be routed to the Internet, you can select from blocks of IP addresses reserved as Private IP addresses. More ...
IGRP (Interior Gateway Routing Protocol)
IGRP (Interior Gateway Routing Protocol) is a routing protocol like RIP, however, it scales better than RIP because it uses a sophisticated metric based on bandwidth and delay, and has other advantages. More ...
