ECCouncil 312-38 Practice Test - Questions Answers, Page 14

RG-59 type of coaxial cable is used for cable TV and cable modems.

Answer option D is incorrect. RG-8 coaxial cable is primarily used as a backbone in an Ethernet LAN environment and often connects one wiring closet to another. It is also known as 10Base5 or ThickNet.

Answer option A is incorrect. RG-62 coaxial cable is used for ARCNET and automotive radio antennas.

Answer option C is incorrect. RG-58 coaxial cable is used for Ethernet networks. It uses baseband signaling and 50-Ohm terminator. It is also known as 10Base2 or ThinNet.

The hop limit field in the IPv6 header is decremented by 1 for each router that forwards a packet. The packet is discarded when the hop limit field reaches zero.

Answer option B is incorrect. Next header is an 8-bit field that specifies the next encapsulated protocol.

Answer option A is incorrect. Flow label is a 20-bit field that is used for specifying special router handling from source to destination for a sequence of packets.

Answer option C is incorrect. Traffic class is an 8-bit field that specifies the Internet traffic priority delivery value.

Emanation security is one of the types of computer security that deals with protection against spurious signals emitted by electrical equipment in the system, such as electromagnetic emission (from displays), visible emission (displays may be visible through windows), and audio emission (sounds from printers, etc).

Answer option D is incorrect. Hardware security helps in dealing with the vulnerabilities in the handling of hardware. Answer option B is incorrect. Physical security helps in dealing with protection of computer hardware and associated equipment.

Answer option A is incorrect. Communication security helps in dealing with the protection of data and information during transmission.

A router is a device that routes data packets between computers in different networks. It is used to connect multiple networks, and it determines the path to be taken by each data packet to its destination computer. A router maintains a routing table of the available routes and their conditions. By using this information, along with distance and cost algorithms, the router determines the best path to be taken by the data packets to the destination computer. A router can connect dissimilar networks, such as Ethernet, FDDI, and Token Ring, and route data packets among them. Routers operate at the network layer (layer 3) of the Open Systems Interconnection (OSI) model.

A gateway is a network point that acts as an entrance to another network. On the Internet, a node or stopping point can be either a gateway node or a host (endpoint) node. Both the computers of Internet users and the computers that serve pages to users are host nodes. The computers that control traffic within a company's network or at a local Internet service provider (ISP) are gateway nodes. In the network for an enterprise, a computer server acting as a gateway node is often also acting as a proxy server and a firewall server. A gateway is often associated with both a router, which knows where to direct a given packet of data that arrives at the gateway, and a switch, which furnishes the actual path in and out of the gateway for a given packet. Most of the gateways operate at the application layer, but can operate at the network or session layer of the OSI model.

Answer option C is incorrect. A repeater operates only at the physical layer of the OSI model. Answer option B is incorrect. A bridge operates at the data link layer of the OSI model.

The session layer of the OSI/RM controls the dialogues (connections) between computers. It establishes, manages and terminates the connections between the local and remote application. It provides for full-duplex, half-duplex, or simplex operation, and establishes checkpointing, adjournment, termination, and restart procedures. The OSI model made this layer responsible for graceful close of sessions, which is a property of the Transmission Control Protocol, and also for session check pointing and recovery, which is not usually used in the Internet Protocol Suite. The Session Layer is commonly implemented explicitly in application environments that use remote procedure calls.

Single key encryption uses a single word or phrase as the key. The same key is used by the sender to encrypt and the receiver to decrypt. Sender and receiver initially need to have a secure way of passing the key from one to the other. With TLS or SSL this would not be possible. Symmetric encryption is a type of encryption that uses a single key to encrypt and decrypt data. Symmetric encryption algorithms are faster than public key encryption. Therefore, it is commonly used when a message sender needs to encrypt a large amount of data. Data Encryption Standard (DES) uses the symmetric encryption key algorithm to encrypt data.

A security policy is defined as the document that describes the scope of an organization's security requirements. Information security policies are usually documented in one or more information security policy documents. The policy includes the assets that are to be protected. It also provides security solutions to provide necessary protection against the security threats.

Ettercap is a Unix and Windows tool for computer network protocol analysis and security auditing. It is capable of intercepting traffic on a network segment, capturing passwords, and conducting active eavesdropping against a number of common protocols. It is a free open source software. Ettercap supports active and passive dissection of many protocols (including ciphered ones) and provides many features for network and host analysis.

Answer option C is incorrect. BackTrack is a Linux distribution distributed as a Live CD, which is used for penetration testing. It allows users to include customizable scripts, additional tools and configurable kernels in personalized distributions. It contains various tools, such as Metasploit integration, RFMON injection capable wireless drivers, kismet, autoscan-network (network discovering and managing application), nmap, ettercap, wireshark (formerly known as Ethereal).

Answer option A is incorrect. AirSnort is a Linux-based WLAN WEP cracking tool that recovers encryption keys. AirSnort operates by passively monitoring transmissions. It uses Ciphertext Only Attack and captures approximately 5 to 10 million packets to decrypt the WEP keys. Answer option D is incorrect. Aircrack is the fastest WEP/WPA cracking tool used for 802.11a/b/g WEP and WPA cracking.

The 802.11e standard is a proposed enhancement to the 802.11a and 802.11b wireless LAN (WLAN) specifications. It offers quality of service (QoS) features, including the prioritization of data, voice, and video transmissions. 802.11e enhances the 802.11 Media Access Control layer (MAC layer) with a coordinated time division multiple access (TDMA) construct, and adds error-correcting mechanisms for delay-sensitive applications such as voice and video. Answer option D is incorrect. 802.11h refers to the amendment added to the IEEE 802.11 standard for Spectrum and Transmit Power Management Extensions.

Answer option B is incorrect. 802.11n is an amendment to the IEEE 802.11-2007 wireless networking standard to improve network throughput over the two previous standards - 802.11a and 802.11g - with a significant increase in the maximum raw data rate from 54 Mbit/s to 600 Mbit/s with the use of four spatial streams at a channel width of 40 MHz. Answer option A is incorrect. IEEE 802.15 is a working group of the IEEE 802 and specializes in Wireless PAN (Personal Area Network) standards. It includes seven task groups, which are as follows:

1.Task group 1 (WPAN/Bluetooth)

2.Task group 2 (Coexistence)

3.Task group 3 (High Rate WPAN)

4.Task group 4 (Low Rate WPAN)

5.Task group 5 (Mesh Networking)

6.Task Group 6 (BAN)

7.Task group 7 (VLC)