Cybersecurity Essentials by unknow

Author:unknow
Language: eng
Format: epub
ISBN: 9781119362456
Publisher: Wiley
Published: 2018-09-11T00:00:00+00:00

FIGURE 15.1 A Network-Switch Connection

Switches collect MAC address information to keep track of the devices attached to them. As they interact with those devices, they record their MAC information in an onboard memory structure called a MAC address table.

When a switch receives a packet of network information at one of its ports, it can direct the information to its intended receiver provided the address of the receiver is known. If the address is not known, the switch will broadcast the information to all of its ports. Because information traveling through the switch is generally only sent to the port where it is intended, the performance of the entire network is improved greatly.

Switches can also be used to create logically secured virtual local area networks (VLANs). A VLAN is a security topology that restricts the visibility of network traffic by limiting the movement of network packets so that they only pass between designated ports.

Network switches are typically grouped into one of two categories by their configuration options. Unmanaged switches are Plug and Play (PnP) devices that do not include any options for user configuration. These tend to be low price units intended for use in residential and small office settings, so they are rarely found in business and enterprise networks.

The other category of switches is referred to as managed switches. These devices have programmable management functions built into them that enable administrators to configure them for the specific network environment in which they will be used. As such, they provide some type of management console that the administrator can use to set parameters. Common management interfaces include:

Command-Line Programming This format provides a very efficient and direct text-based method of programming the switch’s settings. Command-line programming requires the administrator to be aware of the instruction set and parameter variables available for setting the different parameters.

Web-Browser-Based Interfaces These interfaces provide a more graphical, menu-driven tool for setting key switch parameters. A Simple Network Management Protocol (SNMP) tool is used to permit the administrator to access the switch’s parameters through a remote client using its web browser.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.