ECCouncil 312-38 Practice Test - Questions Answers, Page 2

The Distance Vector Multicast Routing Protocol (DVMRP) is used to share information between routers to transport IP Multicast packets among networks. It uses a reverse path-flooding technique and is used as the basis for the Internet's multicast backbone (MBONE). In particular, DVMRP is notorious for poor network scaling, resulting from reflooding, particularly with versions that do not implement pruning. DVMRP's flat unicast routing mechanism also affects its capability to scale.

Answer option A is incorrect. The Resource Reservation Protocol (RSVP) is a Transport layer protocol designed to reserve resources across a network for an integrated services Internet. RSVP does not transport application data but is rather an Internet control protocol, like ICMP, IGMP, or routing protocols. RSVP provides receiver-initiated setup of resource reservations for multicast or unicast data flows with scaling and robustness.

RSVP can be used by either hosts or routers to request or deliver specific levels of quality of service (QoS) for application data streams. RSVP defines how applications place reservations and how they can leave the reserved resources once the need for them has ended. RSVP operation will generally result in resources being reserved in each node along a path.

Answer option C is incorrect. A remote procedure call (RPC) hides the details of the network by using the common procedure call mechanism familiar to every programmer. Like any ordinary procedure, RPC is also synchronous and parameters are passed to it. A process of the client calls a function on a remote server and remains suspended until it gets back the results.

Answer option D is incorrect. LWAPP (Lightweight Access Point Protocol) is a protocol used to control multiple Wi-Fi wireless access points at once. This can reduce the amount of time spent on configuring, monitoring, or troubleshooting a large network. This also allows network administrators to closely analyze the network.

Fire walking is a technique for gathering information about a remote network protected by a firewall. This technique can be used effectively to perform information gathering attacks. In this technique, an attacker sends a crafted packet with a TTL value that is set to expire one hop past the firewall. If the firewall allows this crafted packet through, it forwards the packet to the next hop. On the next hop, the packet expires and elicits an ICMP "TTL expired in transit" message to the attacker. If the firewall does not allow the traffic, there should be no response, or an ICMP "administratively prohibited" message should be returned to the attacker. A malicious attacker can use firewalking to determine the types of ports/ protocols that can bypass the firewall. To use firewalking, the attacker needs the IP address of the last known gateway before the firewall and the IP address of a host located behind the firewall. The main drawback of this technique is that if an administrator blocks ICMP packets from leaving the network, it is ineffective.

Answer option B is incorrect. 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 C 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 D is incorrect. War dialing or wardialing 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, Bulletin board 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.

The Network News Transfer Protocol (NNTP) is an Internet application protocol used for transporting Usenet news articles (netnews) between news servers and for reading and posting articles by end user client applications. NNTP is designed so that news articles are stored in a central database, allowing the subscriber to select only those items that he wants to read.

Answer option D is incorrect. Network Time Protocol (NTP) is used to synchronize the timekeeping among the number of distributed time servers and clients. It is used for the time management in a large and diverse network that contains many interfaces. In this protocol, servers define the time, and clients have to be synchronized with the defined time. These clients can choose the most reliable source of time defined from the several NTP servers for their information transmission. Answer option C is incorrect. The Data Link Switching Client Access Protocol (DCAP) is an application layer protocol that is used between workstations and routers for transporting SNA/NetBIOS traffic over TCP sessions. It was introduced in order to address a few deficiencies by the Data Link Switching Protocol (DLSw). The DLSw raises the important issues of scalability and efficiency, and since DLSw is a switch-to-switch protocol, it is not efficient when implemented on workstations. DCAP was introduced in order to address these issues.

Answer option B is incorrect. The BOOTP protocol is used by diskless workstations to collect configuration information from a network server. It is also used to acquire a boot image from the server.

A birthday attack is a class of brute force attacks that exploits the mathematics behind the birthday problem in probability theory. It is a type of cryptography attack. The birthday attack depends on the higher likelihood of collisions found between random attack attempts and a fixed degree of permutations.

Answer option D is incorrect. A dictionary attack is a technique for defeating a cipher or authentication mechanism by trying to determine its decryption key or passphrase by searching likely possibilities. A dictionary attack uses a brute-force technique of successively trying all the words in an exhaustive list (from a prearranged list of values). In contrast with a normal brute force attack, where a large proportion key space is searched systematically, a dictionary attack tries only those possibilities which are most likely to succeed, typically derived from a list of words in a dictionary. Generally, dictionary attacks succeed because many people have a tendency to choose passwords which are short (7 characters or fewer), single words found in dictionaries, or simple, easily-predicted variations on words, such as appending a digit.

Answer option A is incorrect. Phishing is a type of internet fraud attempted by hackers. Hackers try to log into system by masquerading as a trustworthy entity and acquire sensitive information, such as, username, password, bank account details, credit card details, etc. After collecting this information, hackers try to use this information for their gain.

Answer option B is incorrect. A replay attack is a form of network attack in which a valid data transmission is maliciously or fraudulently repeated or delayed. This is carried out either by the originator or by an adversary who intercepts the data and retransmits it, possibly as part of a masquerade attack by IP packet substitution.

Integrated Services Digital Network (ISDN) is a digital telephone/telecommunication network that carries voice, data, and video over an existing telephone network infrastructure. It requires an ISDN modem at both the ends of a transmission. ISDN is designed to provide a single interface for hooking up a telephone, fax machine, computer, etc.

ISDN has two levels of service, i.e., Basic Rate Interface (BRI) and Primary Rate Interface (PRI).

Answer option A is incorrect. The Point-to-Point Protocol, or PPP, is a data link protocol commonly used to establish a direct connection between two networking nodes. It can provide connection authentication, transmission encryption privacy, and compression. PPP is commonly used as a data link layer protocol for connection over synchronous and asynchronous circuits, where it has largely superseded the older, non-standard Serial Line Internet Protocol (SLIP) and telephone company mandated standards (such as Link Access Protocol, Balanced (LAPB) in the X.25 protocol suite). PPP was designed to work with numerous network layer protocols, including Internet Protocol (IP), Novell's Internetwork Packet Exchange (IPX), NBF, and AppleTalk.

Answer option D is incorrect. The X.25 protocol, adopted as a standard by the Consultative Committee for International Telegraph and Telephone (CCITT), is a commonly-used network protocol. The X.25 protocol allows computers on different public networks (such as CompuServe, Tymnet, or a TCP/IP network) to communicate through an intermediary computer at the network layer level. X.25's protocols correspond closely to the data-link and physical-layer protocols defined in the Open Systems Interconnection (OSI) communication model.

Answer option B is incorrect. Frame relay is a telecommunication service designed for cost-efficient data transmission for intermittent traffic between local area networks (LANs) and between end-points in a wide area network (WAN). Frame relay puts data in a variable-size unit called a frame. It checks for lesser errors as compared to other traditional forms of packet switching and hence speeds up data transmission. When an error is detected in a frame, it is simply dropped.

The end points are responsible for detecting and retransmitting dropped frames.

Honeynet is a prime example of a high-interaction honeypot. Two or more honeypots on a network form a honeynet. Typically, a honeynet is used for monitoring a larger and/or more diverse network in which one honeypot may not be sufficient. Honeynets and honeypots are usually implemented as parts of larger network intrusion-detection systems. A honeyfarm is a centralized collection of honeypots and analysis tools.

Banner grabbing is an enumeration technique used to glean information about computer systems on a network and the services running its open ports.

Administrators can use this to take inventory of the systems and services on their network. An intruder however can use banner grabbing in order to find network hosts that are running versions of applications and operating systems with known exploits.

Some examples of service ports used for banner grabbing are those used by Hyper Text Transfer Protocol (HTTP), File Transfer Protocol (FTP), and Simple Mail Transfer Protocol (SMTP); ports 80, 21, and 25 respectively. Tools commonly used to perform banner grabbing are Telnet, which is included with most operating systems, and Netcat.

For example, one could establish a connection to a target host running a Web service with netcat, then send a bad html request in order to get information about the service on the host: [root@prober] nc www.targethost.com 80

HEAD / HTTP/1.1

HTTP/1.1 200 OK

Date: Mon, 11 May 2009 22:10:40 EST

Server: Apache/2.0.46 (Unix) (Red Hat/Linux)

Last-Modified: Thu, 16 Apr 2009 11:20:14 PST

ETag: "1986-69b-123a4bc6"

Accept-Ranges: bytes

Content-Length: 1110

Connection: close

Content-Type: text/html

The administrator can now catalog this system or an intruder now knows what version of Apache to look for exploits.

This program takes a user-supplied string and copies it into 'buffer1', which can hold up to 10 bytes of data. If a user sends more than 10 bytes, it would result in a buffer overflow.

NetRanger is the complete network configuration and information toolkit that includes the following tools: a 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.