Free Practice Questions for ISC SSCP Exam

SMTP (Simple Mail Transfer Protocol) works as a message transfer agent.

Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2001, Page 821.

One the most secure implementations of firewall architectures is the screened-subnet firewall. It employs two packet-filtering routers and a bastion host. Like a screened host firewall, this firewall supports both packet-filtering and proxy services.

Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 93).

The data link layer contains the Logical Link Control sublayer and the Media Access Control (MAC) sublayer.

Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 83).

TCP and UDP are implemented at the transport layer (layer 4).

Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 82).

The RARP protocol sends out a packet, which includes its MAC address and a request to be informed of the IP address that should be assigned to that MAC address.

ARP does the opposite by broadcasting a request to find the Ethernet address that matches a known IP address.

ICMP supports packets containing error, control, and informational messages (e.g. PING).

UDP runs over IP and is used primarily for broadcasting messages over a network.

Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 87.

Port 119 is normally used for the Network News Transfer Protocol. It is thus not need for a mail server, which would normally listen to ports 25 (SMTP), 110 (POP3) and 143 (IMAP).

Source: STREBE, Matthew and PERKINS, Charles, Firewalls 24seven, Sybex 2000, Chapter 1: Understanding Firewalls.

The reverse address resolution protocol (RARP) sends out a packet including a MAC address and a request to be informed of the IP address that should be assigned to that MAC.

Diskless workstations do not have a full operating system but have just enough code to know how to boot up and broadcast for an IP address, and they may have a pointer to the server that holds the operating system. The diskless workstation knows its hardware address, so it broadcasts this information so that a listening server can assign it the correct IP address.

As with ARP, Reverse Address Resolution Protocol (RARP) frames go to all systems on the subnet, but only the RARP server responds. Once the RARP server receives this request, it looks in its table to see which IP address matches the broadcast hardware address. The server then sends a message that contains its IP address back to the requesting computer. The system now has an IP address and can function on the network.

The Bootstrap Protocol (BOOTP) was created after RARP to enhance the functionality that RARP provides for diskless workstations. The diskless workstation can receive its IP address, the name server address for future name resolutions, and the default gateway address from the BOOTP server. BOOTP usually provides more functionality to diskless workstations than does RARP.

The evolution of this protocol has unfolded as follows: RARP evolved into BOOTP, which evolved into DHCP.

The following are incorrect answers:

NAT is a tool that is used for masking true IP addresses by employing internal addresses.

ARP does the opposite of RARP, it finds the MAC address that maps with an existing IP address.

Data Link layer The Data Link layer is not a protocol; it is represented at layer 2 of the OSI model. In the TCP/IP model, the Data Link and Physical layers are combined into the Network Access layer, which is sometimes called the Link layer or the Network Interface layer.

Reference(s) used for this question:

Harris, Shon (2012-10-25). CISSP All-in-One Exam Guide, 6th Edition, Telecommunications and Network Security, Page 584-585 and also 598. For Kindle users see Kindle Locations 12348-12357. McGraw-Hill.

and

KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 87).

A server cluster is a group of independent servers, which are managed as a single system, that provides higher availability, easier manageability, and greater scalability.

Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 67.

Firewalls tend to give a false sense of security. They can be very hard to bypass but they need to be properly configured. The complexity of configuration rules can introduce a vulnerability when the person responsible for its configuration does not fully understand all possible options and switches. Denial of service attacks mainly concerns availability.

Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2002, Chapter 3: Telecommunications and Network Security (page 412).

Remotre Procedure Call (RPC) is the only of the above choices to operate at the session layer (layer 5).

All of the other answers were wrong.

LPD operates at layer 7

SPX operates at layer 4

IGMP operates at layer 3.

Routers are switching devices that operate at the network layer (layer 3) by examining network addresses.

Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 111).

This is one of the tricky negative question. You have to pay close attention to the word EXCEPT within the question.

The SSH transport layer is a secure, low level transport protocol. It provides strong encryption, cryptographic host authentication, and integrity protection.

Authentication in this protocol level is host-based; this protocol does not perform user authentication. A higher level protocol for user authentication can be designed on top of this protocol.

The protocol has been designed to be simple and flexible to allow parameter negotiation, and to minimize the number of round-trips. The key exchange method, public key algorithm, symmetric encryption algorithm, message authentication algorithm, and hash algorithm are all negotiated. It is expected that in most environments, only 2 round-trips will be needed for full key exchange, server authentication, service request, and acceptance notification of service request. The worst case is 3 round-trips.

The following are incorrect answers:

"Remote log-on" is incorrect. SSH does provide remote log-on.

"Command execution" is incorrect. SSH does provide command execution.

"Port forwarding" is incorrect. SSH does provide port forwarding. SSH also has a wonderful feature called SSH Port Forwarding, sometimes called SSH Tunneling, which allows you to establish a secure SSH session and then tunnel arbitrary TCP connections through it. Tunnels can be created at any time, with almost no effort and no programming, which makes them very appealing. See the article below in the reference to take a look at SSH Port Forwarding in detail, as it is a very useful but often misunderstood technology. SSH Port Forwarding can be used for secure communications in a myriad of different ways.

You can see a nice tutorial on the PUTTY web site on how to use PUTTY to do port forwarding at:

http://www.cs.uu.nl/technical/services/ssh/putty/puttyfw.html

Reference(s) used for this question:

RFC 4253 at https://www.ietf.org/rfc/rfc4253.txt

and

SSH Port Forwarding by Symantec

Only fiber optic cables are not affected by crosstalk or interference.

For your exam you should know the information about transmission media:

Copper Cable

Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.

Copper has been used in electric wiring since the invention of the electromagnet and the telegraph in the 1820s.The invention of the telephone in 1876 created further demand for copper wire as an electrical conductor.

Copper is the electrical conductor in many categories of electrical wiring. Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Copper and its alloys are also used to make electrical contacts. Electrical wiring in buildings is the most important market for the copper industry. Roughly half of all copper mined is used to manufacture electrical wire and cable conductors.

Copper Cable

Image Source - http://i00.i.aliimg.com/photo/v0/570456138/FRLS_HR_PVC_Copper_Cable.jpg

Coaxial cable

Coaxial cable, or coax (pronounced 'ko.aks), is a type of cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket. The term coaxial comes from the inner conductor and the outer shield sharing a geometric axis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, who patented the design in 1880.Coaxial cable differs from other shielded cable used for carrying lower-frequency signals, such as audio signals, in that the dimensions of the cable are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a radio frequency transmission line.

Coaxial cable are expensive and does not support many LAN's. It supports data and video

Coaxial Cable

Image Source - http://www.tlc-direct.co.uk/Images/Products/size_3/CARG59.JPG

Fiber optics

An optical fiber cable is a cable containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed. Different types of cable are used for different applications, for example long distance telecommunication, or providing a high-speed data connection between different parts of a building.

Fiber optics used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.

Radio System

Radio systems are used for short distance,cheap and easy to tap.

Radio is the radiation (wireless transmission) of electromagnetic signals through the atmosphere or free space.

Information, such as sound, is carried by systematically changing (modulating) some property of the radiated waves, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form.

Fiber Optics

Image Source - http://aboveinfranet.com/wp-content/uploads/2014/04/fiber-optic-cables-above-infranet-solutions.jpg

Microwave radio system

Microwave transmission refers to the technology of transmitting information or energy by the use of radio waves whose wavelengths are conveniently measured in small numbers of centimetre; these are called microwaves.

Microwaves are widely used for point-to-point communications because their small wavelength allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna. This allows nearby microwave equipment to use the same frequencies without interfering with each other, as lower frequency radio waves do. Another advantage is that the high frequency of microwaves gives the microwave band a very large information-carrying capacity; the microwave band has a bandwidth 30 times that of all the rest of the radio spectrum below it. A disadvantage is that microwaves are limited to line of sight propagation; they cannot pass around hills or mountains as lower frequency radio waves can.

Microwave radio transmission is commonly used in point-to-point communication systems on the surface of the Earth, in satellite communications, and in deep space radio communications. Other parts of the microwave radio band are used for radars, radio navigation systems, sensor systems, and radio astronomy.

Microwave radio systems are carriers for voice data signal, cheap and easy to tap.

Microwave Radio System

Image Source - http://www.valiantcom.com/images/applications/e1_digital_microwave_radio.gif

Satellite Radio Link

Satellite radio is a radio service broadcast from satellites primarily to cars, with the signal broadcast nationwide, across a much wider geographical area than terrestrial radio stations. It is available by subscription, mostly commercial free, and offers subscribers more stations and a wider variety of programming options than terrestrial radio.

Satellite radio link uses transponder to send information and easy to tap.

The following answers are incorrect:

Copper Cable - Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.

Radio System - Radio systems are used for short distance,cheap and easy to tap.

Satellite Radio Link - Satellite radio link uses transponder to send information and easy to tap.

The following reference(s) were/was used to create this question:

CISA review manual 2014 page number 265 &

Official ISC2 guide to CISSP CBK 3rd Edition Page number 233

The greatest danger from BootP or DHCP (Dynamic Host Control Protocol) is from an intruder on the network impersonating a DHCP server and thereby misconfiguring the DHCP clients. Other choices are possible consequences of DHCP impersonation.

Source: STREBE, Matthew and PERKINS, Charles, Firewalls 24seven, Sybex 2000, Chapter 4: Sockets and Services from a Security Viewpoint.

IEEE 802.3 specifies the standard for Ethernet and uses CSMA/CD, not token-passing.

Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 104).

It is the Transport Layer that is responsible for reliable end-to-end data transfer between end systems.

The following answers are incorrect:

Network Layer. Is incorrect because the Network Layer is the OSI layer that is responsible for routing, switching, and subnetwork access across the entire OSI environment.

Data Link Layer. Is incorrect because the Data Link Layer is the serial communications path between nodes or devices without any intermediate switching nodes.

Presentation Layer. Is incorrect because the Presentation Layer is the OSI layer that determines how application information is represented (i.e., encoded) while in transit between two end systems.

Each data packet is assigned the IP address of the sender and the IP address of the recipient. The term network refers to the part of the IP address that identifies each network. The terms host and node refer to the parts of the IP address that identify a specific machine on a network.

Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 87.

This is not a benefit of a firewall. Most firewalls are limited when it comes to preventing the spread of viruses.

This question is testing your knowledge of Malware and Firewalls. The keywords within the questions are "usually" and "virus". Once again to come up with the correct answer, you must stay within the context of the question and really ask yourself which of the 4 choices is NOT usually done by a firewall.

Some of the latest Appliances such as Unified Threat Management (UTM) devices does have the ability to do virus scanning but most first and second generation firewalls would not have such ability. Remember, the questions is not asking about all possible scenarios that could exist but only about which of the 4 choices presented is the BEST.

For the exam you must know your general classes of Malware. There are generally four major classes of malicious code that fall under the general definition of malware:

1. Virus: Parasitic code that requires human action or insertion, or which attaches itself to another program to facilitate replication and distribution. Virus-infected containers can range from e-mail, documents, and data file macros to boot sectors, partitions, and memory fobs. Viruses were the first iteration of malware and were typically transferred by floppy disks (also known as “sneakernet”) and injected into memory when the disk was accessed or infected files were transferred from system to system.

2. Worm: Self-propagating code that exploits system or application vulnerabilities to replicate. Once on a system, it may execute embedded routines to alter, destroy, or monitor the system on which it is running, then move on to the next system. A worm is effectively a virus that does not require human interaction or other programs to infect systems.

3. Trojan Horse: Named after the Trojan horse of Greek mythology (and serving a very similar function), a Trojan horse is a general term referring to programs that appear desirable, but actually contain something harmful. A Trojan horse purports to do one thing that the user wants while secretly performing other potentially malicious actions. For example, a user may download a game file, install it, and begin playing the game. Unbeknownst to the user, the application may also install a virus, launch a worm, or install a utility allowing an attacker to gain unauthorized access to the system remotely, all without the user’s knowledge.

4. Spyware: Prior to its use in malicious activity, spyware was typically a hidden application injected through poor browser security by companies seeking to gain more information about a user’s Internet activity. Today, those methods are used to deploy other malware, collect private data, send advertising or commercial messages to a system, or monitor system input, such as keystrokes or mouse clicks.

The following answers are incorrect:

reduces the risks of external threats from malicious hackers. This is incorrect because a firewall can reduce the risks of external threats from malicious hackers.

reduces the threat level on internal system. This is incorrect because a firewall can reduce the threat level on internal system.

allows centralized management and control of services. This is incorrect because a firewall can allow centralize management and control of services.

Reference(s) used for this question:

Hernandez CISSP, Steven (2012-12-21). Official (ISC)2 Guide to the CISSP CBK, Third Edition ((ISC)2 Press) (Kindle Locations 3989-4009). Auerbach Publications. Kindle Edition.

The MAC address is 48 bits long, 24 of which identify the vendor, as provided by the IEEE. The other 24 bits are provided by the vendor.

A media access control address (MAC address) is a unique identifier assigned to network interfaces for communications on the physical network segment. MAC addresses are used for numerous network technologies and most IEEE 802 network technologies, including Ethernet. Logically, MAC addresses are used in the media access control protocol sublayer of the OSI reference model.

MAC addresses are most often assigned by the manufacturer of a network interface card (NIC) and are stored in its hardware, such as the card's read-only memory or some other firmware mechanism. If assigned by the manufacturer, a MAC address usually encodes the manufacturer's registered identification number and may be referred to as the burned-in address. It may also be known as an Ethernet hardware address (EHA), hardware address or physical address. This is can be contrasted to a programmed address, where the host device issues commands to the NIC to use an arbitrary address. An example is many SOHO routers, where the ISP grants access to only one MAC address (used previously to inserting the router) so the router must use that MAC address on its Internet-facing NIC. Therefore the router administrator configures a MAC address to override the burned-in one.

A network node may have multiple NICs and each must have one unique MAC address per NIC.

See diagram below from Wikipedia showing the format of a MAC address. :

MAC Address format

Reference(s) used for this question:

http://en.wikipedia.org/wiki/MAC_address

The Point-to-Point Protocol (PPP) was designed to support multiple network types over the same serial link, just as Ethernet supports multiple network types over the same LAN. PPP replaces the earlier Serial Line Internet Protocol (SLIP) that only supports IP over a serial link. PPTP is a tunneling protocol.

Source: STREBE, Matthew and PERKINS, Charles, Firewalls 24seven, Sybex 2000, Chapter 3: TCP/IP from a Security Viewpoint.