SSCP Exam Dumps - Systems Security Certified Practitioner

ATM is an example of a fast packet-switching network that can be used for either data, voice or video, but packets are of fixed size.

Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2002, chapter 7: Telecommunications and Network Security (page 455).

If the protocol field has a value of 2 then it would indicate it was IGMP.

The following answers are incorrect:

TCP. Is incorrect because the value for a TCP protocol would be 6.

UDP. Is incorrect because the value for an UDP protocol would be 17.

ICMP. Is incorrect because the value for an ICMP protocol would be 1.

This layer of the DoD Model is also sometimes called Transport in some books but the proper name is Host-to-Host as per the RFC document.

The host-to-host layer provides for reliable end-to-end communications, ensures the data's error-free delivery, handles the data's packet sequencing, and maintains the data's integrity.

It is comparable to the transport layer of the OSI model.

Reference(s) used for this question:

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

and

http://technet.microsoft.com/en-us/library/cc786900%28v=ws.10%29.aspx

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 85).

When using link encryption, packets have to be decrypted at each hop and encrypted again.

Information staying encrypted from one end of its journey to the other is a characteristic of end-to-end encryption, not link encryption.

Link Encryption vs. End-to-End Encryption

Link encryption encrypts the entire packet, including headers and trailers, and has to be decrypted at each hop.

End-to-end encryption does not encrypt the IP Protocol headers, and therefore does not need to be decrypted at each hop.

L2F (Layer 2 Forwarding) provides no authentication or encryption. It is a Protocol that supports the creation of secure virtual private dial-up networks over the Internet.

At one point L2F was merged with PPTP to produce L2TP to be used on networks and not only on dial up links.

IPSec is now considered the best VPN solution for IP environments.

Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2002, Chapter 8: Cryptography (page 507).

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.

Attenuation is the loss of signal strength as it travels. The longer a cable, the more at tenuation occurs, which causes the signal carrying the data to deteriorate. This is why standards include suggested cable-run lengths. If a networking cable is too long, attenuation may occur. Basically, the data are in the form of electrons, and these electrons have to “swim” through a copper wire. However, this is more like swimming upstream, because there is a lot of resistance on the electrons working in this media. After a certain distance, the electrons start to slow down and their encoding format loses form. If the form gets too degraded, the receiving system cannot interpret them any longer. If a network administrator needs to run a cable longer than its recommended segment length, she needs to insert a repeater or some type of device that will amplify the signal and ensure it gets to its destination in the right encoding format.

Attenuation can also be caused by cable breaks and malfunctions. This is why cables should be tested. If a cable is suspected of attenuation problems, cable testers can inject signals into the cable and read the results at the end of the cable.

The following answers are incorrect:

Crosstalk - Crosstalk is one example of noise where unwanted electrical coupling between adjacent lines causes the signal in one wire to be picked up by the signal in an adjacent wire.

Noise - Noise is also a signal degradation but it refers to a large amount of electrical fluctuation that can interfere with the interpretation of the signal by the receiver.

Delay distortion - Delay distortion can result in a misinterpretation of a signal that results from transmitting a digital signal with varying frequency components. The various components arrive at the receiver with varying delays.

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 229 &

CISSP All-In-One Exam guide 6th Edition Page Number 561

Digital Signal level 1 (DS-1) is the framing specification used for transmitting digital signals at 1.544 Mbps on a T1 facility. DS-0 is the framing specification used in transmitting digital signals over a single 64 Kbps channel over a T1 facility. DS-3 is the framing specification used for transmitting digital signals at 44.736 Mbps on a T3 facility. DS-2 is not a defined framing specification.

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 114).