a certification study guide

... Authentication POP (APOP), 436 Authentication server, 197 Automatic private IP addressing (APIPA), 323 B Bandwidth, 50–52, 89 Baseband, 242, 583 Basic rate interface (BRI), 111 WAN, 362 Bastion ... Media, 3 Media access control. See MAC Media attachment unit (MAU), 72 Megabits per second (Mbps), 51 Mesh topology, 27 Messaging application program interface (MAPI), 257 Metropolitan area network, ... Network access security, 468–469 AAA, 431–432 authentication. See Authentication Network address translation (NAT), 291, 345–346, 601 Network analyzer. See Protocol analyzer Network attached

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... Trang 2CompTIA Network+ Certification Study Guide Trang 3This page intentionally left blankTrang 4CompTIA Network+ Certification Study Guide Exam N10-004 2E Robert J Shimonski Technical Editor ... limitation may not apply to you You should always use reasonable care, including backup and other appropriate precautions, when working with computers, networks, data, and files Syngress Media®, ... Developmental Editor: Gary Byrne Copy editor: diacriTech, Chennai, India Indexer: diacriTech, Chennai, India Cover Designer: Alisa Andreola For information on rights, translations, and bulk sales,

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... the areas of pro-gramming, hardware, database administration, graphic design, and network administration In 2007, he was awarded a police commendation for his work on developing a system to track ... of California Los Angeles (UCLA), Stanford Research Institute, University of California Santa Barbara, and University of Utah), it allowed researchers and government to exchange information and ... distribute data, share employee information, access shared data-bases, online programs, and other components that are needed or wanted by an organization The major difference between an intranet and the

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... started the National Aeronautics and Space Administration (NASA), began launching space missions, and achieved the first manned landing on the moon in 1969 Using computers that employed only a ... DNS, a number like 207.46.250.222 can be translated to a friendly domain name such as microsoft.com In 1984, DNS became part of ARPANet, and would eventually play a major part resolving domain names ... on a high-speed storage area network (SAN) that can be configured as a high-speed back-bone between your systems, disks, and data With a RAID array, disk failure, is imminent but solvable As

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... established between corporate offices that are separated by a physical distance extending further than normal LAN media covers. VPNs are available as software (such as Windows VPN, available ... (RAS). They can sim- ply dial into their local ISPs and create a virtual tunnel to the office. A tunnel is created by wrapping (or encapsulating) a data packet inside another data packet and ... 2003 and 2008) and hardware (firewalls such as Cisco PIX or ASA and Nokia/Checkpoint) implementations. In general, software implementa- tions are easier to maintain. However, hardware implementations

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... these packets and display them in your friend’s e-mail program As you can see by this example, there are many different kinds of LANs and WANs that data may pass through LANs may be as small as a ... isn’t a defining factor WANs are often owned and managed by more than one organization Each LAN that is part of the WAN may be managed by individuals or IT departments, and either maintains their ... computer and the device Using a PAN allows you to do such things as update a calendar in a PDA, address book in a cell phone, and other tasks that are supported by the device CAN A CAN is a campus area

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... of network you have LANs are small networks within a limited area of a few miles, MANs are within a metro-politan area, and WANs interconnect LANs over a wide area These char-acteristics define ... Offices are part of a LAN and a WAN? A Office A and B B Office B and C C Office C and D D The entire network (Office A, B, C, and D) An organization has offices in two countries Office A is a small ... lines A MAN is a group of LANs that are internetworked within a local ■ ■ geographic area, which the IEEE defines as being 50 km or less in diameter Trang 3ChApTEr 1: Network Fundamentals 38 ExAM

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... signals to transmit data. Bandwidth Bandwidth is a measurement of the amount of data that can be passed over a cable in a given amount of time. If you compare cabling to a highway, and data to ... capacity varies depending on the media being used. Table 2.1 Bandwidth Capacity of Physical Media Media Standard Cable Type Bandwidth Capacity 10Base2 Coax 10 Mbps 10Base5 Coax 10 Mbps 10BaseT ... will carry the data at varying speeds and distances. Although some cables can carry the data for a hundred meters or so, others can span greater distances, connecting widely spaced areas. In

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... Hardware Loopback Adapter A hardware loopback adapter is a way to test the ports on a system without having to connect to an external device. For example, you can use a serial loopback adapter ... determine what and where the problem is. Cable testers are tools that can analyze the capability of a cable to carry signals and can find breaks or other problems in the wire. In addition to cable ... see later in this chapter when we discuss cabling and cable creation, twisted-pair and coaxial cabling may require replacement of a bad section with a new section of cable. Twisted-pair may

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... connec-tor or a cabling tray and transceiver called a media attachment unit (MAU) are connected to the cable Another cable called an attachment unit interface (AUI) that can be up to 50 m in length ... the safest method of keeping cables together, as staples or other methods can damage cable CABlE MANAGEMENT Cable management and termination of cabling runs becomes important when working as a Network ... to transmit data The optical fiber in the cable allows data to transmit faster and over greater distances, making it useful for connecting different locations at high speeds MEdIA STANdArdS As

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... Terminating a Coaxial Cable Now that you have learned about coaxial cable and how to identify it, we will learn how to terminate a coaxial connector on to a RG type cable. As with twisted-pair cable ... made an official standard. Category 6 is another enhancement to the previous grades and provides support for 10 Gigabit Ethernet. It is officially a part of the 568A standard, making it a standard ... crimper, a pair of 2. coaxial cable strippers, the coaxial cable itself, and BNC connectors. Use the cable cutter to cut a length of coaxial cable from a bulk spool 3. if you have one available.

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... that data can travel along a cable in several ways, using a simplex, half-duplex, or full duplex data transfer When simplex is used, data moves in a single direction Half-duplex allows data to ... coaxial cabling to transmit data at speeds of 10 Mbps ■ ■ across cable segments that are up to 185 m in length 10Base5 uses coaxial cabling to transmit data at speeds of 10 Mbps ■ ■ across cable ... measurement of the amount of data that can be ■ ■ passed over a cable in a given amount of time Attenuation occurs when data transmitted over media weakens over ■ ■ distance Cable Testers and Troubleshooting

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... bridge Bridges are intelligent devices and have the ability to forward packets of data based on MAC addresses A bridge can look at a packet of data and determine the source and destination involved ... devices mapped to the OSI layers at which they operate. Table 3.1 Mapping of Network Devices to the OSI Model oSI layer devices Application Gateway Presentation Gateway Session Gateway Transport Gateway ... Gateway Network Router, multilayer or Layer 3 switches, gateway Data Link NIC, bridge, Layer 2 switches, access point, gateway Physical Hub, MAU, repeater, gateway Trang 6Network Devices 101Hubs Although

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... cable modem is similar to an analog modem in that it translates data into a form that can be transmitted, and retranslates it into data the computer can understand When data is sent using cable ... converts digital data to an analog wave, DSL transmits and receives data digitally across the phone line’s twisted-pair cable Because data isn’t converted, a higher bandwidth is available to transfer ... grouping of data channels With ISDN, voice and data are carried by these channels Two types of chan-nels are used for a single ISDN connection: a B channel and a D channel Each channel has a specific

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... are network cards that have the same address, but each manufacturer is assigned a range by the various network standards organizations, and they use only that range Within the range, a manufacturer ... takes a signal from a digital medium and multiplexes it Although a CSU and a DSU can be sepa-rate components, they are generally packaged as a single unit The CSU is used to connect a terminal ... device to modulate and demodulate between digital and analog formats The CSU/DSU can be a separate component that attaches to a router and provides an interface between the routers, but many newer

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... Firewall The application level firewall understands the data at the application level Application layer firewalls operate at the application, presentation, and session layers Data at the application ... further than a normal LAN VPNs are available in software (such as Windows network operating sys-tems) and hardware (firewalls such as Nokia/Checkpoint and SonicWALL) implementations Generally speaking, ... Service (RAS) servers They can simply dial into their local ISPs and create a virtual tunnel to the office A tunnel is created by wrapping (or encapsulating) a data packet inside another data packet

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... take advantage of caching and load balancing so  that the amount of data transmitted across networks and requests processed by a server are reduced. Advanced Features of a Switch A VLAN allows ... that loops will result and flood the network. VLAN A VLAN is a virtual LAN that allows messages to be broadcast to all of the network devices that are in the same broadcast domain. A broadcast ... for. Broadcast messages are the messages that are sent out to all of the  nodes in a broadcast domain. A broadcast domain is a logical divi- sion of computers that can communicate with one another

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... that supports a longer distance B Install a passive hub to increase the distance that data can travel along the cable C Install a NIC to increase the distance that data can travel along the cable ... we take a look at a senior manager who is attending a status meeting in a conference room where a limited number of data ports will be available to access e-mail, databases, and other information ... impacting the day-to-day use of the facilities In addition, the APs could be located in an area of the library that has restricted access and is physically secure from daily activities Roaming A

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... data is divided and simultaneously transmitted on as many frequencies as possible within a particular frequency band (the channel) DSSS adds redundant bits of data known as chips to the data ... buildings, and the curvature of the earth to name a few Assuming that the surface being impacted is relatively flat and smooth, a large majority of the original signal will be reflected off at a different ... larger problem refraction could present Absorption and Scattering As disruptive as reflection and refraction are, absorption and scattering can absolutely destroy an electromagnetic signal wave

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... digital assistants) and almost all portable computers do or can have infrared capabilities Infrared devices typically can achieve a maximum data throughput of 4 Mbps, but as it is a light-based ... rather is the focus of the Infrared Data Association (IrDA) The IrDA was founded in 1993 as a member-funded organization whose primary function is to create and promote a standardized data transmission ... mechanism using infrared light Infrared data transmission has been used for many applications in a non-nonstandard manner by Hewlett Packard calculators and printers Now, most PDAs (personal digital

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