CompTIA A+ Practice Tests. Docter Quentin

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D. If you need to trace a wire in a wall from one location to another, a tone generator and probe is the right tool to use. It consists of two pieces: a tone generator and a probe. To use it, attach one end to one end of the cable, such as the end at the computer. Then go to the patch panel with the other end of the probe to locate the cable. These are lifesavers when the cables are not properly labeled.

B. Dynamic Host Configuration Protocol (DHCP) dynamically assigns IP addresses and other IP configuration information to network clients.

D. Shielded twisted pair (STP) cabling has a foil shield surrounding the wire pairs to decrease electrical interference. Some STP cables also shield individual wire pairs. Unshielded twisted pair (UTP) does not have the shielding. Both types use RJ-45 connectors, can follow the T568A wiring standard, and can be produced as plenum-rated cable that does not produce poisonous gas when burned.

D. The connectors shown are ST connectors, which are used with fiber-optic cable. ST connectors are the most popular fiber connector, and they attach with a BNC-like locking mechanism.

B. Switches work at Layer 2 as do bridges, and they provide centralized connectivity just like hubs. Switches examine the Layer 2 header of the incoming packet and forward it properly to the right port and only that port. Switches are multiport bridges.

B. Email is pushed from clients to servers using the Simple Mail Transfer Protocol (SMTP). SMTP uses port 25.

C. Of the Wi-Fi standards, 802.11n has the longest range by default, at roughly 70 meters indoors and 250 meters outdoors. 802.11ac is newer and faster than 802.11n, but it transmits exclusively in the 5GHz range, which restricts its functional distance.

C. Multimeters are versatile electronic measuring tools. A multimeter can measure voltage, current, and resistance on a wire.

A. Simple Network Management Protocol (SNMP) gathers and manages network performance information. A management device called an SNMP server can be set up to collect data from these devices (called agents) and ensure that your network is operating properly.

C. One of the two most popular broadband choices for home use is Digital Subscriber Line (DSL). It utilizes existing phone lines and provides fairly reliable high-speed access. Most DSL subscriptions are asymmetrical, meaning they offer faster download speeds than upload speeds.

B. Wi-Fi Protected Access (WPA) was the first Wi-Fi encryption standard to implement the use of the Temporal Key Integrity Protocol (TKIP). Whereas WEP used a static 40- or 128-bit key, TKIP uses a 128-bit dynamic per-packet key. It generates a new key for each packet sent.

C. When setting up wireless access points, it’s good practice to have their ranges overlap to ensure there is no loss of communication when roaming in the network’s area. However, to avoid problems, it’s best to set up the access points with nonoverlapping channels.

A. Simple Mail Transfer Protocol (SMTP), Post Office Protocol 3 (POP3), and Internet Message Access Protocol (IMAP) are all email protocols. SMTP is for sending email. POP3 and IMAP are for downloading email.

A. Ethernet over power can make Ethernet connections by using electrical outlets. For it to work, both devices must be on the same electrical circuit.