Network Types - 3

Content Networks

Content networks (CNs) were developed to ease users’ access to Internet resources. CNs are aware of layers 4–7 of the OSI Reference Model and use this information to make intelligent decisions about how to obtain the information for the user or users. CNs come in the following categories: content distribution, content routing, content switching, content management, content delivery, and intelligent network
services, which include QoS, security, multicasting, and virtual private networks (VPNs).

Companies deploy basically two types of CNs:

Network Types - 2

Metropolitan Area Networks

A metropolitan area network (MAN) is a hybrid between a LAN and a WAN. Like a WAN, it connects two or more LANs in the same geographic area. A MAN, for example, might connect two different buildings or offices in the same city. However, whereas WANs typically provide low- to medium-speed access, MANs provide high-speed connections, such as T1 (1.544 Mbps) and optical services.

The optical services provided include SONET (the Synchronous Optical Network standard) and SDH (the Synchronous Digital Hierarchy standard).With these optical services, carriers can

Network Types - 1

Networks come in a wide variety of types. The most common are LANs and WANs, but there are many other types of networks, including metropolitan area networks (MANs), storage area networks (SANs), content networks (CNs), intranets and extranets, VPNs, and others. The following sections provide a brief overview of each of these network types.

Local Area Networks

Local area networks (LANs) are used to connect networking devices that are

Mesh Topology

Meshing generically describes how devices are connected together. There are two types of meshed topologies: partial and full. In a partially meshed environment, every device is not connected to every other device. In a fully meshed environment, every device is connected to every other device. Figure 1-3 shows examples of these two types of topologies.

Note that like the topologies in the preceding section, partial and full mesh can be seen from

Physical Versus Logical Topology

A distinction needs to be made between physical and logical topologies. A physical topology describes how devices are physically cabled together. For instance, 10BaseT has a physical star topology and FDDI has a physical dual ring topology. A logical topology describes how devices communicate across the physical topology.

The physical and logical topologies are independent of each other. For example, any variety of Ethernet uses a logical bus topology when

Network Topology

When you are cabling up your computers and networking devices, various types of topologies can be used. A topology defines how the devices are connected. Figure 1-1 shows examples of topologies that different media types use.

A point-to-point topology has a single connection between two devices. In this topology, two devices can directly communicate without interference from other devices. These types of connections are

Introduction to Networking

Networks
A network is basically all of the components (hardware and software) involved in connecting computers across small and large distances. Networks are used to provide easy access to information, thus increasing productivity for users. This section covers some of the components involved with networking, as well as the basic types of topologies used to connect networking devices, including computers.


Components
One of the main components of networking is applications, which