EC-COUNCIL EC-COUNCIL Certifications 312-38 Questions & Answers

• Question 371:

  Which of the following types of VPN uses the Internet as its main backbone, allowing users, customers, and branch offices to access corporate network resources across various network architectures?

  A. PPTP VPN

  B. Remote access VPN

  C. Extranet-based VPN

  D. Intranet-based VPN

  Correct Answer: C

  An extranet-based VPN uses the Internet as its main backbone network, allowing users, customers, and branch offices to access corporate network resources across various network architectures. Extranet VPNs are almost identical to intranet VPNs, except that they are intended for external business partners. Answer option D is incorrect. An intranet-based VPN is an internal, TCP/IP-based, password-protected network usually implemented for networks within a common network infrastructure having various physical locations. Intranet VPNs are secure VPNs that have strong encryption. Answer option B is incorrect. A remote access VPN is one of the types of VPN that involves a single VPN gateway. It allows remote users and telecommuters to connect to their corporate LAN from various points of connections. It provides significant cost savings by reducing the burden of long distance charges associated with dial-up access. Its main security concern is authentication, rather than encryption. Answer option A is incorrect. The PPTP VPN is one of the types of VPN technology.

• Question 372:

  Which of the following is a tool that runs on the Windows OS and analyzes iptables log messages to detect port scans and other suspicious traffic?

  A. Nmap

  B. Hping

  C. NetRanger

  D. PSAD

  Correct Answer: D

  PSAD is a tool that runs on the Windows OS and analyzes iptables log messages to detect port scans and other suspicious traffic. It includes many signatures from the IDS to detect probes for various backdoor programs such as EvilFTP, GirlFriend, SubSeven, DDoS tools (mstream, shaft), and advanced port scans (FIN, NULL, XMAS). If it is combined with fwsnort and the Netfilter string match extension, it detects most of the attacks described in the Snort rule set that involve application layer data. Answer option C is incorrect. NetRanger is the complete network configuration and information toolkit that includes the following tools: Ping tool, Trace Route tool, Host Lookup tool, Internet time synchronizer, Whois tool, Finger Unix hosts tool, Host and port scanning tool, check multiple POP3 mail accounts tool, manage dialup connections tool, Quote of the day tool, and monitor Network Settings tool. These tools are integrated in order to use an application interface with full online help. NetRanger is designed for both new and experienced users. This tool is used to help diagnose network problems and to get information about users, hosts, and networks on the Internet or on a user computer network. NetRanger uses multi-threaded and multi-connection technologies in order to be very fast and efficient. Answer option B is incorrect. Hping is a free packet generator and analyzer for the TCP/IP protocol. Hping is one of the de facto tools for security auditing and testing of firewalls and networks. The new version of hping, hping3, is scriptable using the Tcl language and implements an engine for string based, human readable description of TCP/IP packets, so that the programmer can write scripts related to low level TCP/IP packet manipulation and analysis in very short time. Like most tools used in computer security, hping is useful to both system administrators and crackers (or script kiddies). Answer option A is incorrect. Nmap is a free open-source utility for network exploration and security auditing. It is used to discover computers and services on a computer network, thus creating a "map" of the network. Just like many simple port scanners, Nmap is capable of discovering passive services. In addition, Nmap may be able to determine various details about the remote computers. These include operating system, device type, uptime, software product used to run a service, exact version number of that product, presence of some firewall techniques and, on a local area network, even vendor of the remote network card. Nmap runs on Linux, Microsoft Windows, etc.

• Question 373:

  Which of the following is a distributed application architecture that partitions tasks or workloads between service providers and service requesters? Each correct answer represents a complete solution. Choose all that apply.

  A. Client-server computing

  B. Peer-to-peer (P2P) computing

  C. Client-server networking

  D. Peer-to-peer networking

  Correct Answer: AC

  Client-server networking is also known as client-server computing. It is a distributed application architecture that partitions tasks or workloads between service providers (servers) and service requesters, called clients. Often clients and

  servers operate over a computer network on separate hardware. A server machine is a high-performance host that is running one or more server programs which share its resources with clients. A client does not share any of its resources,

  but requests a server's content or service function. Clients therefore initiate

  communication sessions with servers which await (listen to) incoming requests.

  Answer options D and B are incorrect. Peer-to-peer (P2P) computing or networking is a distributed application architecture that partitions tasks or workloads between peers. Peers are equally privileged, equipotent participants in the

  application. They are said to form a peer-to-peer network of nodes. Peer-to-peer networking (also known simply as peer networking) differs from client-server networking, where certain devices have the responsibility to provide or "serve" data,

  and other devices consume or otherwise act as "clients" of those servers.

• Question 374:

  Which of the following is a distributed multi-access network that helps in supporting integrated communications using a dual bus and distributed queuing?

  A. Logical Link Control

  B. Token Ring network

  C. Distributed-queue dual-bus

  D. CSMA/CA

  Correct Answer: C

  In telecommunication, a distributed-queue dual-bus network (DQDB) is a distributed multi-access network that helps in supporting integrated communications using a dual bus and distributed queuing, providing access to local or metropolitan area networks, and supporting connectionless data transfer, connection-oriented data transfer, and isochronous communications, such as voice communications. IEEE 802.6 is an example of a network providing DQDB access methods. Answer option B is incorrect. A Token Ring network is a local area network (LAN) in which all computers are connected in a ring or star topology and a bit- or token-passing scheme is used in order to prevent the collision of data between two computers that want to send messages at the same time. The Token Ring protocol is the second most widely-used protocol on local area networks after Ethernet. The IBM Token Ring protocol led to a standard version, specified as IEEE

  802.5. Both protocols are used and are very similar. The IEEE 802.5 Token Ring technology provides for data transfer rates of either 4 or 16 megabits per second. Answer option A is incorrect. The IEEE 802.2 standard defines Logical Link Control (LLC). LLC is the upper portion of the data link layer for local area networks. Answer option D is incorrect. Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) is an access method used by wireless networks (IEEE 802.11). In this method, a device or computer that transmits data needs to first listen to the channel for an amount of time to check for any activity on the channel. If the channel is sensed as idle, the device is allowed to transmit data. If the channel is busy, the device postpones its transmission. Once the channel is clear, the device sends a signal telling all other devices not to transmit data, and then sends its packets. In Ethernet (IEEE 802.3) networks that use CSMA/CD, the device or computer continues to wait for a time and checks if the channel is still free. If the channel is free, the device transmits packets and waits for an acknowledgment signal indicating that the packets were received.

• Question 375:

  Which of the following is the practice of sending unwanted e-mail messages, frequently with commercial content, in large quantities to an indiscriminate set of recipients? Each correct answer represents a complete solution. Choose all that apply.

  A. E-mail spam

  B. Junk mail

  C. Email spoofing

  D. Email jamming

  Correct Answer: AB

  E-mail spam, also known as unsolicited bulk email (UBE), junk mail, or unsolicited commercial email (UCE), is the practice of sending unwanted e-mail messages, frequently with commercial content, in large quantities to an indiscriminate set of recipients. Answer option C is incorrect. Email spoofing is a fraudulent email activity in which the sender address and other parts of the email header are altered to appear as though the email originated from a different source. Email spoofing is a technique commonly used in spam and phishing emails to hide the origin of the email message. By changing certain properties of the email, such as the From, Return-Path and Reply-To fields (which can be found in the message header), ill-intentioned users can make the email appear to be from someone other than the actual sender. The result is that, although the email appears to come from the address indicated in the From field (found in the email headers), it actually comes from another source. Answer option D is incorrect. Email jamming is the use of sensitive words in e-mails to jam the authorities that listen in on them by providing a form of a red herring and an intentional annoyance. In this attack, an attacker deliberately includes "sensitive" words and phrases in otherwise innocuous emails to ensure that these are picked up by the monitoring systems. As a result, the senders of these emails will eventually be added to a "harmless" list and their emails will be no longer intercepted, hence it will allow them to regain some privacy.

• Question 376:

  Which of the following is an attack on a website that changes the visual appearance of the site and seriously damages the trust and reputation of the website?

  A. Website defacement

  B. Zero-day attack

  C. Spoofing

  D. Buffer overflow

  Correct Answer: A

  Website defacement is an attack on a website that changes the visual appearance of the site. These are typically the work of system crackers, who break into a Web server and replace the hosted website with one of their own. Sometimes,

  the Defacer makes fun of the system administrator for failing to maintain server security. Most times, the defacement is harmless; however, it can sometimes be used as a distraction to cover up more sinister actions such as uploading

  malware.

  A high-profile website defacement was carried out on the website of the company SCO Group following its assertion that Linux contained stolen code. The title of the page was changed from Red Hat vs. SCO to SCO vs. World with various

  satirical content.

  Answer option D is incorrect. Buffer overflow is a condition in which an application receives more data than it is configured to accept. This usually occurs due to programming errors in the application. Buffer overflow can terminate or crash the

  application.

  Answer option B is incorrect. A zero-day attack, also known as zero-hour attack, is a computer threat that tries to exploit computer application vulnerabilities which are unknown to others, undisclosed to the software vendor, or for which no

  security fix is available. Zero-day exploits (actual code that can use a security hole to carry out an attack) are used or shared by attackers before the software vendor knows about the vulnerability. User awareness training is the most effective

  technique to mitigate such attacks.

  Answer option C is incorrect. Spoofing is a technique that makes a transmission appear to have come from an authentic source by forging the IP address, email address, caller ID, etc. In IP spoofing, a hacker modifies packet headers by

  using someone else's IP address to hide his identity. However, spoofing cannot be used while surfing the Internet, chatting on-line, etc. because forging the source IP address causes the responses to be misdirected.

• Question 377:

  Which of the following techniques is used for drawing symbols in public places for advertising an open Wi-Fi wireless network?

  A. Spamming

  B. War driving

  C. War dialing

  D. Warchalking

  Correct Answer: D

  Warchalking is the drawing of symbols in public places to advertise an open Wi-Fi wireless network. Having found a Wi-Fi node, the warchalker draws a special symbol on a nearby object, such as a wall, the pavement, or a lamp post. The name warchalking is derived from the cracker terms war dialing and war driving. Answer option B is incorrect. War driving, also called access point mapping, is the act of locating and possibly exploiting connections to wireless local area networks while driving around a city or elsewhere. To do war driving, one needs a vehicle, a computer (which can be a laptop), a wireless Ethernet card set to work in promiscuous mode, and some kind of an antenna which can be mounted on top of or positioned inside the car. Because a wireless LAN may have a range that extends beyond an office building, an outside user may be able to intrude into the network, obtain a free Internet connection, and possibly gain access to company records and other resources. Answer option C is incorrect. War dialing is a technique of using a modem to automatically scan a list of telephone numbers, usually dialing every number in a local area code to search for computers, BBS systems, and fax machines. Hackers use the resulting lists for various purposes, hobbyists for exploration, and crackers (hackers that specialize in computer security) for password guessing. Answer option A is incorrect. Spamming is the technique of flooding the Internet with a number of copies of the same message. The most widely recognized form of spams are e-mail spam, instant messaging spam, Usenet newsgroup spam, Web search engine spam, spam in blogs, online classified ads spam, mobile phone messaging spam, Internet forum spam, junk fax transmissions, social networking spam, television advertising and file sharing network spam.

• Question 378:

  Which of the following is a network that supports mobile communications across an arbitrary number of wireless LANs and satellite coverage areas?

  A. LAN

  B. WAN

  C. GAN

  D. HAN

  Correct Answer: C

  A global area network (GAN) is a network that is used for supporting mobile communications across an arbitrary number of wireless LANs, satellite coverage areas, etc. The key challenge in mobile communications is handing off the user communications from one local coverage area to the next. Answer option B is incorrect. A wide area network (WAN) is a geographically dispersed telecommunications network. The term distinguishes a broader telecommunication structure from a local area network (LAN). A wide area network may be privately owned or rented, but the term usually connotes the inclusion of public (shared user) networks. An intermediate form of network in terms of geography is a metropolitan area network (MAN). A wide area network is also defined as a network of networks, as it interconnects LANs over a wide geographical area. Answer option D is incorrect. A home area network (HAN) is a residential LAN that is used for communication between digital devices typically deployed in the home, usually a small number of personal computers and accessories, such as printers and mobile computing devices. Answer option A is incorrect. The Local Area Network (LAN) is a group of computers connected within a restricted geographic area, such as residence, educational institute, research lab, and various other organizations. It allows the users to share files and services, and is commonly used for intra-office communication. The LAN has connections with other LANs via leased lines, leased services, or by tunneling across the Internet using the virtual private network technologies.

• Question 379:

  Which of the following cables is made of glass or plastic and transmits signals in the form of light?

  A. Coaxial cable

  B. Twisted pair cable

  C. Plenum cable

  D. Fiber optic cable

  Correct Answer: D

  Fiber optic cable is also known as optical fiber. It is made of glass or plastic and transmits signals in the form of light. It is of cylindrical shape and consists of three concentric sections: the core, the cladding, and the jacket. Optical fiber carries much more information than conventional copper wire and is in general not subject to electromagnetic interference and the need to retransmit signals. Most telephone company's long-distance lines are now made of optical fiber. Transmission over an optical fiber cable requires repeaters at distance intervals. The glass fiber requires more protection within an outer cable than copper. Answer option B is incorrect. Twisted pair cabling is a type of wiring in which two conductors (the forward and return conductors of a single circuit) are twisted together for the purposes of canceling out electromagnetic interference (EMI) from external sources. It consists of the following twisted pair cables: Shielded Twisted Pair: Shielded Twisted Pair (STP) is a special kind of copper telephone wiring used in some business installations. An outer covering or shield is added to the ordinary twisted pair telephone wires; the shield functions as a ground. Twisted pair is the ordinary copper wire that connects home and many business computers to the telephone company. Shielded twisted pair is often used in business installations. Unshielded Twisted Pair: Unshielded Twisted Pair (UTP) is the ordinary wire used in home. UTP cable is also the most common cable used in computer networking. Ethernet, the most common data networking standard, utilizes UTP cables. Twisted pair cabling is often used in data networks for short and medium length connections because of its relatively lower costs compared to optical fiber and coaxial cable.UTP is also finding increasing use in video applications, primarily in security cameras. Many middle to high-end cameras include a UTP output with setscrew terminals. This is made possible by the fact that UTP cable bandwidth has improved to match the baseband of television signals. Answer option A is incorrect. Coaxial cable is the kind of copper cable used by cable TV companies between the community antenna and user homes and businesses. Coaxial cable is sometimes used by telephone companies from their central office to the telephone poles near users. It is also widely installed for use in business and corporation Ethernet and other types of local area network. Coaxial cable is called "coaxial" because it includes one physical channel that carries the signal surrounded (after a layer of insulation) by another concentric physical channel, both running along the same axis. The outer channel serves as a ground. Many of these cables or pairs of coaxial tubes can be placed in a single outer sheathing and, with repeaters, can carry information for a great distance. It is shown in the figure below:

  

  Answer option C is incorrect. Plenum cable is cable that is laid in the plenum spaces of buildings. The plenum is the space that can facilitate air circulation for heating and air conditioning systems, by providing pathways for either heated/ conditioned or return airflows. Space between the structural ceiling and the dropped ceiling or under a raised floor is typically considered plenum. However, some drop ceiling designs create a tight seal that does not allow for airflow and therefore may not be considered a plenum air-handling space. The plenum space is typically used to house the communication cables for the building's computer and telephone network.

• Question 380:

  Which of the following representatives of the incident response team takes forensic backups of systems that are the focus of an incident?

  A. Technical representative

  B. Lead investigator

  C. Information security representative

  D. Legal representative

  Correct Answer: A

  A technical representative creates forensic backups of systems that are the focus of an incident and provides valuable information about the configuration of the network and target system.

  Answer option B is incorrect. A lead investigator acts as the manager of the computer security incident response team.

  Answer option D is incorrect. The legal representative looks after legal issues and ensures that the investigation process does not break any law. Answer option C is incorrect. The information security representative informs about the security

  safeguards that may affect their ability to respond to the incident.