ECCouncil 312-38 Practice Test - Questions Answers, Page 31

The Router Log Level directive is used by the sys log server to specify the level of severity of the log. This directive is used to control the types of errors that are sent to the error log by constraining the severity level. Eight different levels are present in the Log Level directive, which are shown below in order of their descending significance:

Number Level Description

0emergEmergencies - system is unusable

1alertAction must be taken immediately

2critCritical Conditions

3errorError conditions

4warnWarning conditions

5notice Normal but significant condition

6infoInformational

7debug Debug-level messages

Note: When a certain level is specified, the messages from all other levels of higher significance will also be reported. For example, when Log Level crit is specified, then messages with log levels of alert and emerg will also be reported.

NetBIOS Extended User Interface (NetBEUI) is a Microsoft proprietary protocol. NetBEUI is usually used in single LANs comprising one to two hundred clients. It is a non-routable protocol. NetBEUI was developed by IBM for its LAN Manager product and has been adopted by Microsoft for its Windows NT, LAN Manager, and Windows for Workgroups products. It permits users to enter a user-friendly computer name into the Windows browser and to map network drives and view shared folders.

Answer option C is incorrect. Voice over Internet Protocol (VoIP) is a general term for a family of transmission technologies for delivery of voice communications over IP networks such as the Internet or other packet-switched networks.

Other terms frequently encountered and synonymous with VoIP are IP telephony, Internet telephony, Voice over Broadband (VoBB), broadband telephony, and broadband phone.

VoIP systems employ session control protocols to control the set-up and tear-down of calls as well as audio codecs that encode speech, allowing transmission over an IP network as digital audio via an audio stream.

Answer option A is incorrect. RADIUS is a client/server protocol that runs in the application layer, using UDP as transport. The Remote Access Server, the Virtual Private Network server, the Network switch with port-based authentication, and the Network Access Server are all gateways that control access to the network, and all have a RADIUS client component that communicates with the RADIUS server. The RADIUS server is usually a background process running on a UNIX or Windows NT machine.

RADIUS serves three functions:

To authenticate users or devices before granting them access to a network; To authorize those users or devices for certain network services; To account for usage of those services.

Answer option D is incorrect. Address Resolution Protocol (ARP) is a computer networking protocol used to determine a network host's Link Layer or hardware address when only its Internet Layer (IP) or Network Layer address is known. This function is critical in local area networking as well as for routing internetworking traffic across gateways (routers) based on IP addresses when the next-hop router must be determined.

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. Zeroday 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.

Answer option A 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.

Updating the anti-virus software regularly is the best way of protecting important data against virus attack.

The Service Location Protocol (SLP, srvloc) is a service discovery protocol that allows computers and other devices to find services in a local area network without prior configuration. SLP has been designed to scale from small, unmanaged networks to large enterprise networks.

Answer option C is incorrect. 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 A 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 D 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.