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CCNAS Chapter 7 CCNA Security 1.0 2012 100%-CCNAS Chapter 7 – CCNA Security: Implementing Network Security (Version 1.0) – Answers – 2011 – 2012

Thứ Tư, 1 tháng 8, 2012

1. Which symmetrical encryption algorithm is the most difficult to crack?

3DES
AES
DES
RSA
SHA
2. What is the basic method used by 3DES to encrypt plaintext?
The data is encrypted three times with three different keys.
The data is encrypted, decrypted, and encrypted using three different keys.
The data is divided into three blocks of equal length for encryption.
The data is encrypted using a key length that is three times longer than the key used for DES.
3. What does it mean when a hashing algorithm is collision resistant?
Exclusive ORs are performed on input data and produce a digest.
It is not feasible to compute the hash given the input data.
It uses a two-way function that computes a hash from the input and output data.
Two messages with the same hash are unlikely to occur.
4. Which three primary functions are required to secure communication across network links? (Choose three.)
accounting
anti-replay protection
authentication
authorization
confidentiality
integrity
5. Which two encryption algorithms are commonly used to encrypt the contents of a message? (Choose two.)
3DES
AES
IPsec
PKI
SHA
6. Which statement describes asymmetric encryption algorithms?
They include DES, 3DES, and AES.
They have key lengths ranging from 80 to 256 bits.
They are also called shared-secret key algorithms.
They are relatively slow because they are based on difficult computational algorithms.
7. Which statement describes the use of keys for encryption?
The sender and receiver must use the same key when using symmetric encryption.
The sender and receiver must use the same key when using asymmetric encryption.
The sender and receiver must use the same keys for both symmetric and asymmetric encryption.
The sender and receiver must use two keys: one for symmetric encryption and another for asymmetric encryption.
8. How do modern cryptographers defend against brute-force attacks?
Use statistical analysis to eliminate the most common encryption keys.
Use an algorithm that requires the attacker to have both ciphertext and plaintext to conduct a successful attack.
Use a keyspace large enough that it takes too much money and too much time to conduct a successful attack.
Use frequency analysis to ensure that the most popular letters used in the language are not used in the cipher message.
9.
Refer to the exhibit. Which type of cipher method is depicted?

Caesar cipher
stream cipher
substitution cipher
transposition cipher
10. Which statement describes a cryptographic hash function?
A one-way cryptographic hash function is hard to invert.
The output of a cryptographic hash function can be any length.
The input of a cryptographic hash function has a fixed length.
A cryptographic hash function is used to provide confidentiality.
11. A customer purchases an item from an e-commerce site. The e-commerce site must maintain proof that the data exchange took place between the site and the customer. Which feature of digital signatures is required?
authenticity of digitally signed data
integrity of digitally signed data
nonrepudiation of the transaction
confidentiality of the public key
12. Which encryption protocol provides network layer confidentiality?
IPsec protocol suite
Keyed MD5
Message Digest 5
Secure Sockets Layer
Secure Hash Algorithm 1
Transport Layer Security
13. Which statement is a feature of HMAC?
HMAC is based on the RSA hash function.
HMAC uses a secret key that is only known to the sender and defeats man-in-the-middle attacks.
HMAC uses a secret key as input to the hash function, adding authentication to integrity assurance.
HMAC uses protocols such as SSL or TLS to provide session layer confidentiality.
14. The network administrator for an e-commerce website requires a service that prevents customers from claiming that legitimate orders are fake. What service provides this type of guarantee?
authentication
confidentiality
integrity
nonrepudiation
15. What is a characteristic of the RSA algorithm?
RSA is much faster than DES.
RSA is a common symmetric algorithm.
RSA is used to protect corporate data in high-throughput, low-latency environments.
RSA keys of 512 bits can be used for faster processing, while keys of 2048 bits can be used for increased securit
16.
Refer to the exhibit. Which encryption algorithm is described in the exhibit?

3DES
AES
DES
RC4
SEAL
17. An administrator requires a PKI that supports a longer lifetime for keys used for digital signing operations than for keys used for encrypting data. Which feature should the PKI support?
certificate keys
nonrepudiation keys
usage keys
variable keys
18. Which two statements correctly describe certificate classes used in the PKI? (Choose two.)
A class 0 certificate is for testing purposes.
A class 0 certificate is more trusted than a class 1 certificate.
The lower the class number, the more trusted the certificate.
A class 5 certificate is for users with a focus on verification of email.
A class 4 certificate is for online business transactions between companies.
19. Two users must authenticate each other using digital certificates and a CA. Which option describes the CA authentication procedure?
The CA is always required, even after user verification is complete.
The users must obtain the certificate of the CA and then their own certificate.
After user verification is complete, the CA is no longer required, even if one of the involved certificates expires.
CA certificates are retrieved out-of-band using the PSTN, and the authentication is done in-band over a network.
20. Why is RSA typically used to protect only small amounts of data?
The keys must be a fixed length.
The public keys must be kept secret.
The algorithms used to encrypt data are slow.
The signature keys must be changed frequently.
21. Which algorithm would provide the best integrity check for data that is sent over the Internet?
MD5
SHA-1
SHA-2
3DES
22. Which characteristic of security key management is responsible for making certain that weak cryptographic keys are not used?
verification
exchange
generation
revocation and destruction
Read more ...

CCNAS Chapter 8 CCNA Security 1.0 2012 100%-CCNAS Chapter 8 – CCNA Security: Implementing Network Security (Version 1.0) – Answers – 2011 – 2012

Thứ Tư, 1 tháng 8, 2012

1. Which IPsec protocol should be selected when confidentiality is required?

tunnel mode
transport mode
authentication header
encapsulating security payload
generic routing encapsulation
2. When using ESP tunnel mode, which portion of the packet is not authenticated?
ESP header
ESP trailer
new IP header
original IP header.
3. When configuring an IPsec VPN, what is used to define the traffic that is sent through the IPsec tunnel and protected by the IPsec process?
crypto map
crypto ACL
ISAKMP policy
IPsec transform set.
4.
Refer to the exhibit. Which two IPsec framework components are valid options when configuring an IPsec VPN on a Cisco ISR router? (Choose two.)

Integrity options include MD5 and RSA.
IPsec protocol options include GRE and AH.
Confidentiality options include DES, 3DES, and AES.
Authentication options include pre-shared key and SHA.
Diffie-Hellman options include DH1, DH2, and DH5..
5.
Refer to the exhibit. Based on the SDM screen, which Easy VPN Server component is being configured?

group policy
transform set
IKE proposal
user authentication.
6.
Refer to the exhibit. Under the ACL Editor, which option is used to specify the traffic to be encrypted on a secure connection?

Access Rules
IPsec Rules
Firewall Rules
SDM Default Rules.
7. What are two authentication methods that can be configured using the SDM Site-to-Site VPN Wizard? 
(Choose two.)
MD5
SHA
pre-shared keys
encrypted nonces
digital certificates.
8.
Refer to the exhibit. A site-to-site VPN is required from R1 to R3. The administrator is using the SDM Site-to-Site VPN Wizard on R1. Which IP address should the administrator enter in the highlighted field?

10.1.1.1
10.1.1.2
10.2.2.1
10.2.2.2
192.168.1.1
192.168.3.1.
9. What is required for a host to use an SSL VPN?
VPN client software must be installed.
A site-to-site VPN must be preconfigured.
The host must be in a stationary location.
A web browser must be installed on the host.
10. Which two statements accurately describe characteristics of IPsec? (Choose two.)
IPsec works at the application layer and protects all application data.
IPsec works at the transport layer and protects data at the network layer.
IPsec works at the network layer and operates over all Layer 2 protocols.
IPsec is a framework of proprietary standards that depend on Cisco specific algorithms.
IPsec is a framework of standards developed by Cisco that relies on OSI algorithms.
IPsec is a framework of open standards that relies on existing algorithms..
11. When configuring a site-to-site IPsec VPN using the CLI, the authentication pre-share command is configured in the ISAKMP policy. Which additional peer authentication configuration is required?
Configure the message encryption algorithm with the encryptiontype ISAKMP policy configuration command.
Configure the DH group identifier with the groupnumber ISAKMP policy configuration command.
Configure a hostname with the crypto isakmp identity hostname global configuration command.
Configure a PSK with the crypto isakmp key global configuration command..
12. Which action do IPsec peers take during the IKE Phase 2 exchange?
exchange of DH keys
negotiation of IPsec policy
verification of peer identity
negotiation of IKE policy sets.
13.
Refer to the exhibit. A network administrator is troubleshooting a GRE VPN tunnel between R1 and R2. Assuming the R2 GRE configuration is correct and based on the running configuration of R1, what must the administrator do to fix the problem?

change the tunnel source interface to Fa0/0
change the tunnel destination to 192.168.5.1
change the tunnel IP address to 192.168.3.1
change the tunnel destination to 209.165.200.225
change the tunnel IP address to 209.165.201.1.
14. When verifying IPsec configurations, which show command displays the encryption algorithm, hash algorithm, authentication method, and Diffie-Hellman group configured, as well as default settings?
show crypto map
show crypto ipsec sa
show crypto isakmp policy
show crypto ipsec transform-set.
15. With the Cisco Easy VPN feature, which process ensures that a static route is created on the Cisco Easy VPN Server for the internal IP address of each VPN client?
Cisco Express Forwarding
Network Access Control
On-Demand Routing
Reverse Path Forwarding
Reverse Route Injection.
16. Which statement describes an important characteristic of a site-to-site VPN?
It must be statically set up.
It is ideally suited for use by mobile workers.
It requires using a VPN client on the host PC.
It is commonly implemented over dialup and cable modem networks.
After the initial connection is established, it can dynamically change connection information..
17. What is the default IKE policy value for authentication?
MD5
SHA
RSA signatures
pre-shared keys
RSA encrypted sconces.
18. Which requirement necessitates using the Step-by-Step option of the SDM Site-to-Site VPN wizard instead of the Quick Setup option?
AES encryption is required.
3DES encryption is required.
Pre-shared keys are to be used.
The remote peer is a Cisco router.
The remote peer IP address is unknown..
19. How many bytes of overhead are added to each IP packet while it is transported through a GRE tunnel?
8
16
24
32.
20. What are two benefits of an SSL VPN? (Choose two.)
It supports all client/server applications.
It supports the same level of cryptographic security as an IPsec VPN.
It has the option of only requiring an SSL-enabled web browser.
The thin client mode functions without requiring any downloads or software.
It is compatible with DMVPNs, Cisco IOS Firewall, IPsec, IPS, Cisco Easy VPN, and NAT..
21. Which UDP port must be permitted on any IP interface used to exchange IKE information between security gateways?
400
500
600
700
22. A network administrator is planning to implement centralized management of Cisco VPN devices to simplify VPN deployment for remote offices and teleworkers. Which Cisco IOS feature would provide this solution?
Cisco Easy VPN
Cisco VPN Client
Cisco IOS SSL VPN
Dynamic Multipoint VPN
23. A user launches Cisco VPN Client software to connect remotely to a VPN service. What does the user select before entering the username and password?
the SSL connection type
the IKE negotiation process
the desired preconfigured VPN server site
the Cisco Encryption Technology to be applied
Read more ...

CCNAS Chapter 6 CCNA Security 1.0 2012 100%-CCNAS Chapter 6 – CCNA Security: Implementing Network Security (Version 1.0) – Answers – 2011 – 2012

Thứ Tư, 1 tháng 8, 2012

1. Which two measures are recommended to mitigate VLAN hopping attacks? (Choose two.)

Use a dedicated native VLAN for all trunk ports.
Place all unused ports in a separate guest VLAN.
Disable trunk negotiation on all ports connecting to workstations.
Enable DTP on all trunk ports.
Ensure that the native VLAN is used for management traffic.
2. As a recommended practice for Layer 2 security, how should VLAN 1 be treated?
All access ports should be assigned to VLAN 1.
All trunk ports should be assigned to VLAN 1.
VLAN 1 should be used for management traffic.
VLAN 1 should not be used.
3. How is a reflector port used in an RSPAN configuration?
It provides a dedicated connection for the IDS device.
It allows an RSPAN session to be backward compatible with a SPAN session.
It acts like a loopback interface in that it reflects the captured traffic to the RSPAN VLAN.
It allows an IDS device to direct malicious traffic to it, isolating that traffic from other areas of the network.
4. Which attack is mitigated by using port security?
LAN storm
VLAN hopping
STP manipulation
MAC address table overflow
5. Which technology is used to protect the switched infrastructure from problems caused by receiving BPDUs on ports that should not be receiving them?
RSPAN
PortFast
Root guard
Loop guard
BPDU guard
6. Which three switch security commands are required to enable port security on a port so that it will dynamically learn a single MAC address and disable the port if a host with any other MAC address is connected? (Choose three.)
switchport mode access
switchport mode trunk
switchport port-security
switchport port-security maximum 2
switchport port-security mac-address sticky
switchport port-security mac-address mac-address
7. When configuring a switch port for port security, what is the default violation mode?
protect
reset
restrict
shutdown
8. Which three statements are true regarding SPAN and RSPAN? (Choose three.)
SPAN can send a copy of traffic to a port on another switch.
RSPAN is required for syslog and SNMP implementation.
SPAN can be configured to send a copy of traffic to a destination port on the same switch.
SPAN can copy traffic on a source port or source VLAN to a destination port on the same switch.
RSPAN is required to copy traffic on a source VLAN to a destination port on the same switch.
RSPAN can be used to forward traffic to reach an IDS that is analyzing traffic for malicious behavior.
9. Which Cisco endpoint security product helps maintain network stability by providing posture assessment, quarantining of noncompliant systems, and remediation of noncompliant systems?
Cisco Access Control Server
Cisco Security Agent workstation
Cisco Intrusion Prevention System router
Cisco Network Admission Control appliance
10. Which attack relies on the default automatic trunking configuration on most Cisco switches?
LAN storm attack
VLAN hopping attack
STP manipulation attack
MAC address spoofing attack
11. With IP voice systems on data networks, which two types of attacks target VoIP specifically? (Choose two.)
CoWPAtty
Kismet
SPIT
virus
vishing
12. Which two elements are part of the Cisco strategy for addressing endpoint security? (Choose two.)
policy compliance using products such as Cisco NAC
network infection monitoring using products such as Cisco Secure ACS
threat protection using products such as Cisco Security Agent
attack detection using products such as Cisco NAC
risk assessment compliance using products such as Cisco Security Agent
13. Which frames are spoofed in STP manipulation attacks?
BPDU
DTP
ISL
802.1q
14. Which option best describes a MAC address spoofing attack?
An attacker gains access to another host and masquerades as the rightful user of that device.
An attacker alters the MAC address of his host to match another known MAC address of a target host.
An attacker alters the MAC address of the switch to gain access to the network device from a rogue host device.
An attacker floods the MAC address table of a switch so that the switch can no longer filter network access based on MAC addresses.
15. What happens when the MAC address notification feature is enabled on a switch?
An SDEE alert is generated, and the switch resets the interface when an invalid MAC address is detected.
An STP multicast notification packet is forwarded to all switches any time a change in the network topology is detected.
A port violation occurs when a MAC address outside of the range of allowed addresses transmits traffic over a secure port.
An SNMP trap is sent to the network management system whenever a new MAC address is added to or an old address is deleted from the forwarding tables.
16. Which device supports the use of SPAN to enable monitoring of malicious activity?
Cisco NAC
Cisco IronPort
Cisco Security Agent
Cisco Catalyst switch
17. An administrator wants to prevent a rogue Layer 2 device from intercepting traffic from multiple VLANs on a network. Which two actions help mitigate this type of activity? (Choose two.)
Disable DTP on ports that require trunking.
Place unused active ports in an unused VLAN.
Secure the native VLAN, VLAN 1, with encryption.
Set the native VLAN on the trunk ports to an unused VLAN.
Turn off trunking on all trunk ports and manually configure each VLAN as required on each port.
18.
Refer to the exhibit. Based on the output generated by the show monitor session 1 command, how will SPAN operate on the switch?

All traffic transmitted from VLAN 10 or received on VLAN 20 is forwarded to FastEthernet 0/1.
All traffic received on VLAN 10 or transmitted from VLAN 20 is forwarded to FastEthernet 0/1.
Native VLAN traffic received on VLAN 10 or transmitted from VLAN 20 is forwarded to FastEthernet 0/1.
Native VLAN traffic transmitted from VLAN 10 or received on VLAN 20 is forwarded to FastEthernet 0/1.
19. How many Cisco Security Agent clients can one Management Center for CSA console support?
1,000
10,000
100,000
1,000,000
20. Which three are SAN transport technologies? (Choose three.)
Fibre Channel
SATA
iSCSI
IP PBX
FCIP
IDE
21. If a switch is configured with the storm-control command and the action shutdown and action trap parameters, which two actions does the switch take when a storm occurs on a port? (Choose two.)
The port is disabled.
The switch is rebooted.
An SNMP log message is sent.
The port is placed in a blocking state.
The switch forwards control traffic only.
Read more ...

CCNAS Chapter 4 CCNA Security 1.0 2012 100%-CCNAS Chapter 4 – CCNA Security: Implementing Network Security (Version 1.0) – Answers – 2011 – 2012

Thứ Tư, 1 tháng 8, 2012

1. Which statement accurately describes Cisco IOS zone-based policy firewall operation?

The pass action works in only one direction.
A router interface can belong to multiple zones.
Service policies are applied in interface configuration mode.
Router management interfaces must be manually assigned to the self zone.
2.Which location is recommended for extended numbered or extended named ACLs?
a location as close to the destination of traffic as possible
a location as close to the source of traffic as possible
a location centered between traffic destinations and sources to filter as much traffic as possible
if using the established keyword, a location close to the destination to ensure that return traffic is allowed
3. When using Cisco IOS zone-based policy firewall, where is the inspection policy applied?
a global service policy
an interface
a zone
a zone pair
4.
Refer to the exhibit. Based on the SDM screen shown, which statement describes the zone-based firewall component being configured?

a class map that inspects all traffic that uses the HTTP, IM, P2P, and email protocols
a class map that prioritizes traffic that uses HTTP first, followed by SMTP, and then DNS
a class map that denies all traffic that uses the HTTP, SMTP, and DNS protocols
a class map that inspects all traffic that uses the HTTP, SMTP, and DNS protocols
a class map that inspects all traffic, except traffic that uses the HTTP, SMTP, and DNS protocols
5.
Refer to the exhibit. Based on the SDM screen shown, which two statements describe the effect this zone-based policy firewall has on traffic? (Choose two.)

HTTP traffic from the in-zone to the out-zone is inspected.
Unmatched traffic to the router from the out-zone is permitted.
ICMP replies from the router to the out-zone are denied.
Traffic from the in-zone to the out-zone is denied if the source address is in the 127.0.0.0/8 range.
Traffic from the in-zone to the out-zone is denied if the destination address is in the 10.1.1.0/29 range.
6. Which type of packet is unable to be filtered by an outbound ACL?
ICMP packet
broadcast packet
multicast packet
router-generated packet
7.
Refer to the exhibit. If a hacker on the outside network sends an IP packet with source address 172.30.1.50, destination address 10.0.0.3, source port 23, and destination port 2447, what does the Cisco IOS firewall do with the packet?

The packet is forwarded, and an alert is generated.
The packet is forwarded, and no alert is generated.
The initial packet is dropped, but subsequent packets are forwarded.
The packet is dropped.
8. Which zone-based policy firewall zone is system-defined and applies to traffic destined for the router or originating from the router?
self zone
system zone
local zone
inside zone
outside zone
9. Which statement correctly describes a type of filtering firewall?
A transparent firewall is typically implemented on a PC or server with firewall software running on it.
A packet-filtering firewall expands the number of IP addresses available and hides network addressing design.
An application gateway firewall (proxy firewall) is typically implemented on a router to filter Layer 3 and Layer 4 information.
A stateful firewall monitors the state of connections, whether the connection is in an initiation, data transfer, or termination state.
10. In addition to the criteria used by extended ACLs, what conditions are used by CBAC to filter traffic?
TCP/IP protocol numbers
IP source and destination addresses
application layer protocol session information
TCP/UDP source and destination port numbers
11. Which statement describes the characteristics of packet-filtering and stateful firewalls as they relate to the OSI model?
Both stateful and packet-filtering firewalls can filter at the application layer.
A stateful firewall can filter application layer information, while a packet-filtering firewall cannot filter beyond the network layer.
A packet-filtering firewall typically can filter up to the transport layer, while a stateful firewall can filter up to the session layer.
A packet-filtering firewall uses session layer information to track the state of a connection, while a stateful firewall uses application layer information to track the state of a connection.
12.
Refer to the exhibit. What is represented by the area marked as “A”?

DMZ
internal network
perimeter security boundary
trusted network
untrusted network
13. Which three actions can a Cisco IOS zone-based policy firewall take if configured with Cisco SDM? (Choose three.)
inspect
evaluate
drop
analyze
pass
forward
14. A router has CBAC configured and an inbound ACL applied to the external interface. Which action does the router take after inbound-to-outbound traffic is inspected and a new entry is created in the state table?
A dynamic ACL entry is added to the external interface in the inbound direction.
The internal interface ACL is reconfigured to allow the host IP address access to the Internet.
The entry remains in the state table after the session is terminated so that it can be reused by the host.
When traffic returns from its destination, it is reinspected, and a new entry is added to the state table.
15. For a stateful firewall, which information is stored in the stateful session flow table?
TCP control header and trailer information associated with a particular session
TCP SYN packets and the associated return ACK packets
inside private IP address and the translated inside global IP address
outbound and inbound access rules (ACL entries)
source and destination IP addresses, and port numbers and sequencing information associated with a particular session
16.
Refer to the exhibit. The ACL statement is the only one explicitly configured on the router. Based on this information, which two conclusions can be drawn regarding remote access network connections? (Choose two.)

SSH connections from the 192.168.1.0/24 network to the 192.168.2.0/24 network are allowed.
Telnet connections from the 192.168.1.0/24 network to the 192.168.2.0/24 network are allowed.
SSH connections from the 192.168.2.0/24 network to the 192.168.1.0/24 network are allowed.
Telnet connections from the 192.168.1.0/24 network to the 192.168.2.0/24 network are blocked.
SSH connections from the 192.168.1.0/24 network to the 192.168.2.0/24 network are blocked.
Telnet connections from the 192.168.2.0/24 network to the 192.168.1.0/24 network are allowed.
17. When configuring a Cisco IOS zone-based policy firewall, which three actions can be applied to a traffic class? (Choose three.)
drop
inspect
pass
reroute
queue
shape
18.
Refer to the exhibit. In a two-interface CBAC implementation, where should ACLs be applied?

inside interface
outside interface
inside and outside interfaces
no interfaces
19. Which two parameters are tracked by CBAC for TCP traffic but not for UDP traffic? (Choose two.)
source port
protocol ID
sequence number
destination port
SYN and ACK flags
20. What is the first step in configuring a Cisco IOS zone-based policy firewall using the CLI?
Create zones.
Define traffic classes.
Define firewall policies.
Assign policy maps to zone pairs.
Assign router interfaces to zones.
21. Which two are characteristics of ACLs? (Choose two.)
Extended ACLs can filter on destination TCP and UDP ports.
Extended ACLs can filter on source and destination IP addresses.
Extended ACLs can filter on source and destination IP addresses.
Standard ACLs can filter on source and destination IP addresses.
Standard ACLs can filter on source and destination TCP and UDP ports.
22. Which type of packets exiting the network of an organization should be blocked by an ACL?
packets that are not encrypted
packets that are not translated with NAT
packets with source IP addresses outside of the organization’s network address space
packets with destination IP addresses outside of the organization’s network address space
23. When logging is enabled for an ACL entry, how does the router switch packets filtered by the ACL?
topology-based switching
autonomous switching
process switching
optimum switching
Read more ...

CCNAS Chapter 5 CCNA Security 1.0 2012 100%-CCNAS Chapter 5 – CCNA Security: Implementing Network Security (Version 1.0) – Answers – 2011 – 2012

Thứ Tư, 1 tháng 8, 2012

1. An IPS sensor has detected the string confidential across multiple packets in a TCP session. Which type of signature trigger and signature type does this describe?

Trigger: Anomaly-based detection
Type: Atomic signature
Trigger: Anomaly-based detection
Type: Composite signature
Trigger: Pattern-based detection
Type: Atomic signature
Trigger: Pattern-based detection
Type: Composite signature
Trigger: Policy-based detection
Type: Atomic signature
Trigger: Policy-based detection
Type: Composite signature
2. A network administrator tunes a signature to detect abnormal activity that might be malicious and likely to be an immediate threat. What is the perceived severity of the signature?
high
medium
low
informational
3. What are two major drawbacks to using HIPS? (Choose two.)
HIPS has difficulty constructing an accurate network picture or coordinating the events happening across the entire network.
HIPS installations are vulnerable to fragmentation attacks or variable TTL attacks.
With HIPS, the network administor must verify support for all the different operating systems used in the network.
If the network traffic stream is encrypted, HIPS is unable to access unencrypted forms of the traffic.
With HIPS, the success or failure of an attack cannot be readily determined.
4. Which type of intrusion detection triggers an action if excessive activity occurs beyond a specified threshold of normal activity?
pattern-based detection
anomaly-based detection
policy-based detection
honey pot-based detection
5. Which two statements characterize a network-based IPS implementation? (Choose two.)
It makes hosts visible to attackers.
It is unable to examine encrypted traffic.
It monitors to see if an attack was successful.
It provides application-level encryption protection.
It is independent of the operating system on hosts.
6. What information is provided by the show ip ips configuration configuration command?
detailed IPS signatures
alarms that were sent since the last reset
the number of packets that are audited
the default actions for attack signatures
7. When editing IPS signatures with SDM, which action drops all future packets from a TCP flow?
Deny Packet Inline
Deny TCP Connection
Deny Attacker Inline
Deny Connection Inline
8.
Refer to the exhibit. A user was installing a Flash Player upgrade when the CSA displayed the dialog box shown. Which default action is taken by CSA if the user does not respond within 4 minutes and 20 seconds?

The action is allowed, and a log entry is recorded.
The action is allowed, and CSA does not prompt the user again.
The action is denied, and a log entry is recorded.
The action is denied, and the FlashPlayerUpdate.exe application is terminated.
9.
Refer to the exhibit. When modifying an IPS signature action, which two check boxes should be selected to create an ACL that denies all traffic from the IP address that is considered the source of the attack and drops the packet and all future packets from the TCP flow? (Choose two.)

Deny Attacker Inline
Deny Connection Inline
Deny Packet Inline
Produce Alert
Reset TCP Connection
10.
Refer to the exhibit. What is the significance of the number 10 in the signature 6130 10 command?

It is the alert severity.
It is the signature number.
It is the signature version.
It is the subsignature ID.
It is the signature fidelity rating.
11. What is a disadvantage of network-based IPS as compared to host-based IPS?
Network-based IPS is less cost-effective.
Network-based IPS cannot examine encrypted traffic.
Network-based IPS does not detect lower level network events.
Network-based IPS should not be used with multiple operating systems.
12. Which two files could be used to implement Cisco IOS IPS with version 5.x format signatures? (Choose two.)
IOS-Sxxx-CLI.bin
IOS-Sxxx-CLI.pkg
IOS-Sxxx-CLI.sdf
realm-cisco.priv.key.txt
realm-cisco.pub.key.txt
13. Why is a network that deploys only IDS particularly vulnerable to an atomic attack?
The IDS must track the three-way handshake of established TCP connections.
The IDS must track the three-way handshake of established UDP connections.
The IDS permits malicious single packets into the network.
The IDS requires significant router resources to maintain the event horizon.
The stateful properties of atomic attacks usually require the IDS to have several pieces of data to match an attack signature.
14.
Refer to the exhibit. Based on the SDM screen shown, which two actions will the signature take if an attack is detected? (Choose two.)

Reset the TCP connection to terminate the TCP flow.
Drop the packet and all future packets from this TCP flow.
Generate an alarm message that can be sent to a syslog server.
Drop the packet and permit remaining packets from this TCP flow.
Create an ACL that denies traffic from the attacker IP address.
15. Which two Cisco IOS commands are required to enable IPS SDEE message logging? (Choose two.)
logging on
ip ips notify log
ip http server
ip ips notify sdee
ip sdee events 500
16.
Refer to the exhibit. Which option tab on the SDM IPS screen is used to view the Top Threats table and deploy signatures associated with those threats?

Create IPS
Edit IPS
Security Dashboard
IPS Migration
17. Which Cisco IOS configuration option instructs the IPS to compile a signature category named ios_ips into memory and use it to scan traffic?
R1(config)# ip ips signature-category
R1(config-ips-category)# category all
R1(config-ips-category-action)# retired false
R1(config)# ip ips signature-category
R1(config-ips-category)# category ios_ips basic
R1(config-ips-category-action)# retired false
R1(config)# ip ips signature-category
R1(config-ips-category)# category all
R1(config-ips-category-action)# enabled true
R1(config)# ip ips signature-category
R1(config-ips-category)# category ios_ips basic
R1(config-ips-category-action)# enabled true
18.
Refer to the exhibit. What is the result of issuing the Cisco IOS IPS commands on router R1?

A named ACL determines the traffic to be inspected.
A numbered ACL is applied to S0/0/0 in the outbound direction.
All traffic that is denied by the ACL is subject to inspection by the IPS.
All traffic that is permitted by the ACL is subject to inspection by the IPS.
19. What are two IPS configuration best practices that can help improve IPS efficiency in a network? (Choose two.)
Configure all sensors to check the server for new signature packs at the same time to ensure that they are all synchronized.
Configure the sensors to simultaneously check the FTP server for new signature packs.
Ensure that signature levels that are supported on the management console are synchronized with the signature packs on the sensors.
Update signature packs manually rather than automatically to maintain close control when setting up a large deployment of sensors.
Place signature packs on a dedicated FTP server within the management network.
20.
Refer to the exhibit. What is the significance of the small red flag waving in the Windows system tray?

Cisco Security Agent is installed but inactive.
Network-based IPS is active and has detected a potential security problem.
Cisco Security Agent is active and has detected a potential security problem.
A network-based IPS sensor has pushed an alert to a host running Cisco Security Agent.
21. Which two benefits does the IPS version 5.x signature format provide over the version 4.x signature format? (Choose two.)
addition of signature micro engines
support for IPX and AppleTalk protocols
addition of a signature risk rating
support for comma-delimited data import
support for encrypted signature parameters
Read more ...

CCNAS Chapter 3 CCNA Security 1.0 2012 100%-CCNAS Chapter 3 – CCNA Security: Implementing Network Security (Version 1.0) – Answers – 2011 – 2012

Thứ Tư, 1 tháng 8, 2012

1. Why is local database authentication preferred over a password-only login?

It specifies a different password for each line or port.
It provides for authentication and accountability.
It requires a login and password combination on console, vty lines, and aux ports.
It is more efficient for users who only need to enter a password to gain entry to a device.
2. What is a characteristic of AAA?
Authorization can only be implemented after a user is authenticated.
Accounting services are implemented prior to authenticating a user.
Accounting services determine which resources the user can access and which operations the user is allowed to perform.
Authorization records what the user does, including what is accessed, the amount of time the resource is accessed, and any changes that were made.
3. Due to implemented security controls, a user can only access a server with FTP. Which AAA component accomplishes this?
accessibility
accounting
auditing
authentication
authorization
4. Which two AAA access method statements are true? (Choose two. )
Character mode provides remote users with access to network resources and requires use of the console, vty, or tty ports.
Character mode provides remote users with access to network resources and requires use of dialup or VPN.
Character mode provides users with administrative privilege EXEC access and requires use of the console, vty, or tty ports.
Packet mode provides users with administrative privilege EXEC access and requires use of dialup or VPN.
Packet mode provides remote users with access to network resources and requires use of dialup or VPN.
Packet mode provides users with administrative privilege EXEC access and requires use of the console, vty, or tty ports.
5. Which two statements describe AAA authentication? (Choose two. )
Server-based AAA authentication is more scalable than local AAA authentication.
Local AAA is ideal for large complex networks because it uses the local database of the router for authentication.
Server-based AAA authentication can use the RADIUS or TACACS+ protocols to communicate between the router and a AAA server.
Server-based AAA authentication is ideal for large complex networks because it uses the local database of the router for authentication.
Local AAA authentication requires the services of an external server, such as the Cisco Secure ACS for Windows Server.
6. What is a difference between using the login local command and using local AAA authentication for authenticating administrator access?
Local AAA authentication supports encrypted passwords; login local does not.
Local AAA provides a way to configure backup methods of authentication; login local does not.
A method list must be configured when using the login local command, but is optional when using local AAA authentication.
The login local command supports the keyword none, which ensures that authentication succeeds, even if all methods return an error.
7.
Refer to the exhibit. Router R1 has been configured as shown, with the resulting log message. On the basis of the information presented, which two AAA authentication statements are true? (Choose two. )

The locked-out user failed authentication.
The locked-out user is locked out for 10 minutes by default.
The locked-out user should have used the username Admin and password Pa55w0rd.
The locked-out user should have used the username admin and password Str0ngPa55w0rd.
The locked-out user stays locked out until the clear aaa local user lockout username Admin command is issued.
8.
Refer to the exhibit. Router R1 is configured as shown. An administrative user attempts to use Telnet from router R2 to router R1 using the interface IP address 10. 10. 10. 1. However, Telnet access is denied. Which option corrects this problem?

The R1 10. 10. 10. 1 router interface must be enabled.
The vty lines must be configured with the login authentication default command.
The aaa local authentication attempts max-fail command must be set to 2 or higher.
The administrative user should use the username Admin and password Str0ngPa55w0rd.
9. When configuring a method list for AAA authentication, what is the effect of the keyword local?
It accepts a locally configured username, regardless of case.
It defaults to the vty line password for authentication.
The login succeeds, even if all methods return an error.
It uses the enable password for authentication.
10. What is a characteristic of TACACS+?
TACACS+ is an open IETF standard.
TACACS+ is backward compatible with TACACS and XTACACS.
TACACS+ provides authorization of router commands on a per-user or per-group basis.
TACACS+ uses UDP port 1645 or 1812 for authentication, and UDP port 1646 or 1813 for accounting
11. Which statement identifies an important difference between TACACS+ and RADIUS?
TACACS+ provides extensive accounting capabilities when compared to RADIUS.
The RADIUS protocol encrypts the entire packet transmission.
The TACACS+ protocol allows for separation of authentication from authorization.
RADIUS can cause delays by establishing a new TCP session for each authorization request.
12. In regards to Cisco Secure ACS, what is a client device?
a web server, email server, or FTP server
the computer used by a network administrator
network users who must access privileged EXEC commands
a router, switch, firewall, or VPN concentrator
13. What is the result if an administrator configures the aaa authorization command prior to creating a user with full access rights?
The administrator is immediately locked out of the system.
The administrator is denied all access except to aaa authorization commands.
The administrator is allowed full access using the enable secret password.
The administrator is allowed full access until a router reboot, which is required to apply changes.
14. When configuring a Cisco Secure ACS, how is the configuration interface accessed?
A Web browser is used to configure a Cisco Secure ACS.
The Cisco Secure ACS can be accessed from the router console.
Telnet can be used to configure a Cisco Secure ACS server after an initial configuration is complete.
The Cisco Secure ACS can be accessed remotely after installing ACS client software on the administrator workstation.
15. Which AAA protocol and feature best support a large ISP that needs to implement detailed accounting for customer invoicing?
TACACS+ because it combines authentication and authorization, but separates accounting
RADIUS because it supports detailed accounting that is required for billing users
TACACS+ because it requires select authorization policies to be applied on a per-user or per-group basis
RADIUS because it requires select authorization policies to be applied on a per-user or per-group basis
16. After accounting is enabled on an IOS device, how is a default accounting method list applied?
Accounting method lists are applied only to the VTY interfaces.
A named accounting method list must be explicitly defined and applied to desired interfaces.
Accounting method lists are not applied to any interfaces until an interface is added to the server group.
The default accounting method list is automatically applied to all interfaces, except those with named accounting method lists.
17.
Refer to the exhibit. In the network shown, which AAA command logs the use of EXEC session commands?

aaa accounting connection start-stop group radius
aaa accounting connection start-stop group tacacs+
aaa accounting exec start-stop group radius
aaa accounting exec start-stop group tacacs+
aaa accounting network start-stop group radius
aaa accounting network start-stop group tacacs+
18. How does a Cisco Secure ACS improve performance of the TACACS+ authorization process?
reduces overhead by using UDP for authorization queries
reduces delays in the authorization queries by using persistent TCP sessions
reduces bandwidth utilization of the authorization queries by allowing cached credentials
reduces number of authorization queries by combining the authorization process with authentication
19.
Refer to the exhibit. Which Cisco Secure ACS menu is required to configure the IP address and secure password of an AAA client?

User Setup
Group Setup
Network Configuration
System Configuration
Interface Configuration
Administration Control
20. What is an effect if AAA authorization on a device is not configured?
Authenticated users are granted full access rights.
User access to specific services is determined by the authentication process.
Character mode authorization is limited, and packet mode denies all requests.
All authorization requests to the TACACS server receive a REJECT response.
Read more ...

CCNAS Chapter 2 CCNA Security 1.0 2012 100% CCNAS Chapter 2 – CCNA Security: Implementing Network Security (Version 1.0) – Answers – 2011 – 2012

Thứ Tư, 1 tháng 8, 2012

1.

Refer to the exhibit. What two pieces of information can be gathered from the generated message? (Choose two. )
This message is a level five notification message.
This message appeared because a minor error occurred requiring further investigation.
This message appeared because a major error occurred requiring immediate action.
This message indicates that service timestamps have been globally enabled.
This message indicates that enhanced security was configured on the vty ports.
2. By default, how many seconds of delay between virtual login attempts is invoked when the login block-for command is configured?
one
two
three
four
five
3.
Refer to the exhibit. Routers R1 and R2 are connected via a serial link. One router is configured as the NTP master, and the other is an NTP client. Which two pieces of information can be obtained from the partial output of the show ntp associations detail command on R2? (Choose two. )

Both routers are configured to use NTPv2.
Router R1 is the master, and R2 is the client.
Router R2 is the master, and R1 is the client.
The IP address of R1 is 192. 168. 1. 2.
The IP address of R2 is 192. 168. 1. 2.
4. What are two characteristics of the SDM Security Audit wizard? (Choose two. )
It uses interactive dialogs and prompts to implement AAA.
It automatically enables Cisco IOS firewall and implements Cisco IOS IPS security configurations to secure the router.
It displays a screen with Fix-it check boxes to let you choose which potential security-related configuration changes to implement.
It requires users to first identify which router interfaces connect to the inside network and which connect to the outside network.
It is initiated from CLI and executes a script in which the managment plane functions and forwarding plane services are tested against known vulnerabilities.
5. If AAA is already enabled, which three CLI steps are required to configure a router with a specific view? (Choose three. )
assign a secret password to the view
assign commands to the view
assign users who can use the view
associate the view with the root view
create a superview using the parser view view-name command
create a view using the parser viewview-name command
6.
Refer to the exhibit. Which statement regarding the JR-Admin account is true?

JR-Admin can issue show, ping, and reload commands.
JR-Admin can issue ping and reload commands.
JR-Admin can issue only ping commands.
JR-Admin can issue debug and reload commands.
JR-Admin cannot issue any command because the privilege level does not match one of those defined.
7. Which recommended security practice prevents attackers from performing password recovery on a Cisco IOS router for the purpose of gaining access to the privileged EXEC mode?
Keep a secure copy of the router Cisco IOS image and router configuration file as a backup.
Disable all unused ports and interfaces to reduce the number of ways that the router can be accessed.
Configure secure administrative control to ensure that only authorized personnel can access the router.
Locate the router in a secure locked room that is accessible only to authorized personnel.
Provision the router with the maximum amount of memory possible.
8. Which three options can be configured by Cisco AutoSecure? (Choose three. )
CBAC
SNMP
syslog
security banner
interface IP address
enable secret password
9.
Refer to the exhibit. Based on the output of the show running-config command, which type of view is SUPPORT?

secret view, with a level 5 encrypted password
root view, with a level 5 encrypted secret password
superview, containing SHOWVIEW and VERIFYVIEW views
CLI view, containing SHOWVIEW and VERIFYVIEW commands
10. Which three services on a router does Cisco SDM One-Step Lockdown enable? (Choose three. )
SNMP
TCP intercepts
SSH access to the router
Cisco Discovery Protocol
password encryption service
firewall on all outside interfaces
11. An administrator defined a local user account with a secret password on router R1 for use with SSH. Which three additional steps are required to configure R1 to accept only encrypted SSH connections? (Choose three. )
configure the IP domain name on the router
enable inbound vty Telnet sessions
generate the SSH keys
configure DNS on the router
enable inbound vty SSH sessions
generate two-way pre-shared keys
12. Which statement describes the operation of the Cisco SDM Security Audit wizard?
The wizard configures a router to prevent unauthorized access.
The wizard compares a router configuration against recommended settings.
The wizard monitors network data and logs possible unauthorized or malicious traffic.
The wizard logs the effectiveness of network security measures for baseline comparisons.
13. An administrator needs to create a user account with custom access to most privileged EXEC commands. Which privilege command is used to create this custom account?
privilege exec level 0
privilege exec level 1
privilege exec level 2
privilege exec level 15
14. Which three areas of router security must be maintained to secure an edge router at the network perimeter? (Choose three. )
physical security
flash security
operating system security
remote access security
router hardening
zone isolation
15. Which service is enabled on a Cisco router by default that can reveal significant information about the router and potentially make it more vulnerable to attack?
HTTP
CDP
FTP
NTP
TFTP
16. Which two operations are required to implement Cisco SDM One-Step Lockdown? (Choose two. )
Choose the One-Step Lockdown feature.
Apply the documented network policies.
Deliver the configuration changes to the router.
Compare the router configuration against recommended settings.
Select the Firewall and ACL task on the SDM Configuration screen.
17. Which statement matches the CLI commands to the SDM wizard that performs similar configuration functions?
aaa configuration commands and the SDM Basic Firewall wizard
auto secure privileged EXEC command and the SDM One-Step Lockdown wizard
class-maps, policy-maps, and service-policy configuration commands and the SDM IPS wizard
setup privileged EXEC command and the SDM Security Audit wizard
18.
Refer to the exhibit. What is the significance of secret 5 in the generated output?

The ADMIN password is encrypted using DH group 5.
The ADMIN password is encrypted via the service password-encryption command.
The ADMIN password is hashed using MD5.
The ADMIN password is hashed using SHA.
19. Which three commands are required to restore a primary bootset from a secure archive on a router on which Cisco IOS resilience is enabled? (Choose three. )
Restart the router in ROM monitor mode and display the secure bootset Cisco IOS image name using the dir command.
Restart the router, enter privileged EXEC mode, and display the secure bootset Cisco IOS image name using the show flash command.
Boot the secure bootset Cisco IOS image using the boot command with the filename.
Copy the secure bootset Cisco IOS image to flash using the copy IOS-backup-image flash command.
Restore the secure configuration file using the copy config-backup flash command.
Restore the secure configuration file using the secure boot-config restore filename command.
20. Which set of commands are required to create a username of admin, hash the password using MD5, and force the router to access the internal username database when a user attempts to access the console?
R1(config)# username admin password Admin01pa55
R1(config)# line con 0
R1(config-line)# login local
R1(config)# username admin password Admin01pa55
R1(config)# line con 0
R1(config-line)# login internal
R1(config)# username admin Admin01pa55 encr md5
R1(config)# line con 0
R1(config-line)# login local
R1(config)# username admin secret Admin01pa55
R1(config)# line con 0
R1(config-line)# login local
R1(config)# username admin secret Admin01pa55
R1(config)# line con 0
R1(config-line)# login internal
21.
Refer to the exhibit. Which two statements describe the current SDM logging setup? (Choose two. )

Buffered logging will be enabled on the router for Logging Level 7 messages.
Buffered logging will be enabled on the syslog server for Logging Level 7 messages.
All messages with a trap level of 4 and higher (less critical) will be logged.
All messages with a trap level of 4 and lower (more critical) will be logged.
The router interface IP address that is connected to the syslog server is 192. 168. 1. 3.
The syslog server IP address is 192. 168. 1. 3.
22. What are two characteristics of SNMP community strings? (Choose two. )
A vulnerability of SNMPv1, SNMPv2, and SNMPv3 is that they send the community strings in plaintext.
Commonly known community strings should be used when configuring secure SNMP.
If the manager sends one of the correct read-only community strings, it can get information and set information in an agent.
SNMP read-only community strings can be used to get information from an SNMP-enabled device.
SNMP read-write community strings can be used to set information on an SNMP-enabled device.
23. What is the minimum recommended modulus key length for keys generated to use with SSH?
256
512
768
1024
2048
24. Which two characteristics apply to Role-Based CLI Access superviews? (Choose two. )
CLI views have passwords, but superviews do not have passwords.
Users logged in to a superview can access all commands specified within the associated CLI views.
A single superview can be shared among multiple CLI views.
Commands cannot be configured for a specific superview.
Deleting a superview deletes all associated CLI views.
25.
Refer to the exhibit. What two facts can be determined from the output? (Choose two. )

The Cisco IOS image and configuration files have been properly secured.
ROMmon mode will be inaccessible upon entering the privileged EXEC reload command.
The Cisco IOS Resilient Configuration feature is enabled.
The Cisco IOS Resilient Configuration feature has detected an image version mismatch.
The Cisco IOS configuration files have been erased.
26. What are three requirements that must be met if an administrator wants to maintain device configurations via secure in-band management? (Choose three. )
network devices configured to accommodate SSH
a separate network segment connecting all management devices
at least one router acting as a terminal server
encryption of all remote access management traffic
connection to network devices through a production network or the Internet
direct access to the console ports of all network devices
Read more ...

CCNAS Chapter 1 CCNA Security 1.0 2012 100%-CCNAS Chapter 1 – CCNA Security: Implementing Network Security (Version 1.0) – Answers – 2011 – 2012

Thứ Tư, 1 tháng 8, 2012

1. What are the basic phases of attack that can be used by a virus or worm in sequential order?

paralyze, probe, penetrate, persist, and propagate
probe, penetrate, persist, propagate, and paralyze
penetrate, persist, propagate, paralyze, and probe
persist, propagate, paralyze, probe, and penetrate
2. Which two are characteristics of DoS attacks? (Choose two.)
They always precede access attacks.
They attempt to compromise the availability of a network, host, or application.
They are difficult to conduct and are initiated only by very skilled attackers.
They are commonly launched with a tool called L0phtCrack.
Examples include smurf attacks and ping of death attacks.
3. Users report to the helpdesk that icons usually seen on the menu bar are randomly appearing on their computer screens. What could be a reason that computers are displaying these random graphics?
An access attack has occurred.
A virus has infected the computers.
A DoS attack has been launched against the network.
The computers are subject to a reconnaissance attack.
4. What are three types of access attacks? (Choose three.)
buffer overflow
ping sweep
port redirection
trust exploitation
port scan
Internet information query
5. What occurs during a spoofing attack?
One device falsifies data to gain access to privileged information.
Large amounts of network traffic are sent to a target device to make resources unavailable to intended users.
Improperly formatted packets are forwarded to a target device to cause the target system to crash.
A program writes data beyond the allocated memory to enable the execution of malicious code.
6. What is a characteristic of a Trojan Horse?
A Trojan Horse can be carried in a virus or worm.
A proxy Trojan Horse opens port 21 on the target system.
An FTP Trojan Horse stops anti-virus programs or firewalls from functioning.
A Trojan Horse can be hard to detect because it closes when the application that launched it closes.
7. Which phase of worm mitigation requires compartmentalization and segmentation of the network to slow down or stop the worm and prevent currently infected hosts from targeting and infecting other systems?
containment phase
inoculation phase
quarantine phase
treatment phase
8. Which two statements are characteristics of a virus? (Choose two.)
A virus typically requires end-user activation.
A virus has an enabling vulnerability, a propagation mechanism, and a payload.
A virus replicates itself by independently exploiting vulnerabilities in networks.
A virus provides the attacker with sensitive data, such as passwords.
A virus can be dormant and then activate at a specific time or date.
9. What is a ping sweep?
A ping sweep is a network scanning technique that indicates the live hosts in a range of IP addresses.
A ping sweep is a software application that enables the capture of all network packets sent across a LAN.
A ping sweep is a scanning technique that examines a range of TCP or UDP port numbers on a host to detect listening services.
A ping sweep is a query and response protocol that identifies information about a domain, including the addresses assigned to that domain.
10. Which type of security threat can be described as software that attaches to another program to execute a specific unwanted function?
virus
worm
proxy Trojan horse
Denial of Service Trojan horse
11. A disgruntled employee is using Wireshark to discover administrative Telnet usernames and passwords. What type of network attack does this describe?
Denial of Service
port redirection
reconnaissance
trust exploitation
12. What occurs during the persist phase of a worm attack?
identification of vulnerable targets
modification of system files and registry settings to ensure that the attack code is running
transfer of exploit code through an attack vector
extension of the attack to vulnerable neighboring targets
13. What are the three major components of a worm attack? (Choose three.)
enabling vulnerability
infecting vulnerability
payload
penetration mechanism
probing mechanism
propagation mechanism
14. A network administrator detects unknown sessions involving port 21 on the network. What could be causing this security breach?
An FTP Trojan Horse is executing.
A reconnaissance attack is occurring.
A denial of service attack is occurring.
Cisco Security Agent is testing the network.
15. What are three goals of a port scan attack? (Choose three.)
disable used ports and services
determine potential vulnerabilities
identify active services
identify peripheral configurations
identify operating systems
discover system passwords
16. How is a Smurf attack conducted?
by sending a large number of packets, overflowing the allocated buffer memory of the target device
by sending an echo request in an IP packet larger than the maximum packet size of 65,535 bytes
by sending a large number of ICMP requests to directed broadcast addresses from a spoofed source address on the same network
by sending a large number of TCP SYN packets to a target device from a spoofed source address
17. Which access attack method involves a software program attempting to discover a system password by using an electronic dictionary?
buffer overflow attack
port redirection attack
Denial of Service attack
brute-force attack
IP spoofing attack
packet sniffer attack
18 Which two network security solutions can be used to mitigate DoS attacks? (Choose two.)
virus scanning
data encryption
anti-spoofing technologies
intrusion protection systems
applying user authentication
19. Which phase of worm mitigation involves terminating the worm process, removing modified files or system settings that the worm introduced, and patching the vulnerability that the worm used to exploit the system?
containment
inoculation
quarantine
treatment
20. Which characteristic best describes the network security Compliance domain as specified by the ISO/IEC?
the integration of security into applications
an inventory and classification scheme for information assets
the restriction of access rights to networks, systems, applications, functions, and data
the process of ensuring conformance with security information policies, standards, and regulations
21. Which statement describes phone freaking?
A hacker uses password-cracking programs to gain access to a computer via a dialup account.
A hacker gains unauthorized access to networks via wireless access points.
A hacker mimics a tone using a whistle to make free long-distance calls on an analog telephone network.
A hacker uses a program that automatically scans telephone numbers within a local area, dialing each one in search of computers, bulletin board systems, and fax machines.
22. Which two statements describe access attacks? (Choose two.)
Port redirection attacks use a network adapter card in promiscuous mode to capture all network packets that are sent across a LAN.
Password attacks can be implemented using brute-force attack methods, Trojan Horses, or packet sniffers.
Buffer overflow attacks write data beyond the allocated buffer memory to overwrite valid data or exploit systems to execute malicious code.
Port scanning attacks scan a range of TCP or UDP port numbers on a host to detect listening services.
Trust exploitation attacks can use a laptop acting as a rogue access point to capture and copy all network traffic in a public location on a wireless hotspot.
Read more ...

Ipv6 Rs (ccnp642-901)

Thứ Tư, 23 tháng 5, 2012
The router sends its prefix and then the node adds its interface ID to make its own IPv6 address, thus Answer A is correct.

The following is the actual procedure for IPv6 stateless address autoconfiguration:

(1) The new node on the network generates link local address and allocates it to the interface. Link-local address takes the following form: fe80:0000:0000:0000:0000:

(2) The node confirms that generated link local address is not already used on the same network (DAD: Duplicate Address Detection). At first, the node transmits Neighbor Solicitation (NS) message on the network. If another node is already using the same address, this node sends Neighbor Advertisement (NA) message. The new node that transmitted NS message will use the original link-local address if it receives no NA message after a certain time. If the new node is notified of the duplicate address situation, it will not allocate the link-local address and terminates the interface.

(3) The new node sends Router Solicitation (RS) message on the network to request information, using the link-local address just allocated. RS message transmission is not a must. The node can passively wait for (4).

(4) The node that received RS message (usually a router) sends back Router Advertisement (RA) message. RA message is transmitted periodically, so nodes do not necessarily have to send RS message.

(5) The node receives RA and gets IPv6 address prefix.

(6) The node forms the global IPv6 address by combining prefix and interface ID, just as it did for link-local address.

It should be noted that RA sender, such as router, only sends fixed prefix allocated to the network. In other words, RA sender does not care to whom it sent information. It does not maintain such records. Therefore, if two routers exist on the same network and advertise different prefixes with RAs, receiving node automatically gets both RA to allocate different address on the same interface
Read more ...

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