ENSA 5 Flashcards
Which statement describes a characteristic of Cisco Catalyst 2960 switches?
They are best used as distribution layer switches.
New Cisco Catalyst 2960-C switches support PoE pass-through.
They are modular switches.
They do not support an active switched virtual interface (SVI) with IOS versions prior to 15.x.
New Cisco Catalyst 2960-C switches support PoE pass-through.
Explanation: Cisco Catalyst 2960 switches support one active switched virtual interface (SVI) with IOS versions prior to 15.x. They are commonly used as access layer switches and they are fixed configuration switches.
Which component of the ACI architecture translates application policies into network programming?
the hypervisor
the Application Policy Infrastructure Controller
the Nexus 9000 switch
the Application Network Profile endpoints
the Application Policy Infrastructure Controller
Which two pieces of information should be included in a logical topology diagram of a network? (Choose two.)
device type
cable specification
interface identifier
OS/IOS version
connection type
cable type and identifier
interface identifier
connection type
Explanation: The interface identifier and connection type should be included in a logical topology diagram because they indicate which interface is connected to other devices in the network with a specific type such as LAN, WAN, point-to-point, etc. The OS/IOS version, device type, cable type and identifier, and cable specification are typically included in a physical topology diagram.
Refer to the exhibit. A PC at address 10.1.1.45 is unable to access the Internet. What is the most likely cause of the problem?
The NAT pool has been exhausted.
The wrong netmask was used on the NAT pool.
Access-list 1 has not been configured properly.
The inside and outside interfaces have been configured backwards.
The NAT pool has been exhausted.
Explanation: The output of show ip nat statistics shows that there are 2 total addresses and that 2 addresses have been allocated (100%). This indicates that the NAT pool is out of global addresses to give new clients. Based on the show ip nat translations, PCs at 10.1.1.33 and 10.1.1.123 have used the two available addresses to send ICMP messages to a host on the outside network.
What are two benefits of using SNMP traps? (Choose two.)
They eliminate the need for some periodic polling requests.
They reduce the load on network and agent resources.
They limit access for management systems only.
They can provide statistics on TCP/IP packets that flow through Cisco devices.
They can passively listen for exported NetFlow datagrams.
They eliminate the need for some periodic polling requests.
They reduce the load on network and agent resources.
Which statement accurately describes a characteristic of IPsec?
IPsec works at the application layer and protects all application data.
IPsec is a framework of standards developed by Cisco that relies on OSI algorithms.
IPsec is a framework of proprietary standards that depend on Cisco specific algorithms.
IPsec works at the transport layer and protects data at the network layer.
IPsec is a framework of open standards that relies on existing algorithms.
IPsec is a framework of open standards that relies on existing algorithms.
Explanation: IPsec can secure a path between two network devices. IPsec can provide the following security functions:
Confidentiality – IPsec ensures confidentiality by using encryption.
Integrity – IPsec ensures that data arrives unchanged at the destination using a hash algorithm, such as MD5 or SHA.
Authentication – IPsec uses Internet Key Exchange (IKE) to authenticate users and devices that can carry out communication independently. IKE uses several types of authentication, including username and password, one-time password, biometrics, pre-shared keys (PSKs), and digital certificates.
Secure key exchange- IPsec uses the Diffie-Hellman (DH) algorithm to provide a public key exchange method for two peers to establish a shared secret key.
In a large enterprise network, which two functions are performed by routers at the distribution layer? (Choose two.)
connect users to the network
provide a high-speed network backbone
connect remote networks
provide Power over Ethernet to devices
provide data traffic security
connect remote networks
provide data traffic security
Explanation: In a large enterprise network, the provision of a high-speed network backbone is a function of the core layer. Access layer switches connect users to the network and provide Power over Ethernet to devices. Distribution layer routers provide data traffic security and connections to other networks.
Which two statements describe the use of asymmetric algorithms? (Choose two.)
Public and private keys may be used interchangeably.
If a public key is used to encrypt the data, a public key must be used to decrypt the data.
If a private key is used to encrypt the data, a public key must be used to decrypt the data.
If a public key is used to encrypt the data, a private key must be used to decrypt the data.
If a private key is used to encrypt the data, a private key must be used to decrypt the data.
If a private key is used to encrypt the data, a public key must be used to decrypt the data.
If a public key is used to encrypt the data, a private key must be used to decrypt the data.
Explanation: Asymmetric algorithms use two keys: a public key and a private key. Both keys are capable of the encryption process, but the complementary matched key is required for decryption. If a public key encrypts the data, the matching private key decrypts the data. The opposite is also true. If a private key encrypts the data, the corresponding public key decrypts the data.
Refer to the exhibit. A network administrator has deployed QoS and has configured the network to mark traffic on the VoIP phones as well as the Layer 2 and Layer 3 switches. Where should initial marking occur to establish the trust boundary?
Trust Boundary 4
Trust Boundary 3
Trust Boundary 1
Trust Boundary 2
Trust Boundary 1
Explanation: Traffic should be classified and marked as close to its source as possible. The trust boundary identifies at which device marked traffic should be trusted. Traffic marked on VoIP phones would be considered trusted as it moves into the enterprise network.
What are two benefits of extending access layer connectivity to users through a wireless medium? (Choose two.)
reduced costs
decreased number of critical points of failure
increased flexibility
increased bandwidth availability
increased network management options
reduced costs
increased flexibility
Explanation: Wireless connectivity at the access layer provides increased flexibility, reduced costs, and the ability to grow and adapt to changing business requirements. Utilizing wireless routers and access points can provide an increase in the number of central points of failure. Wireless routers and access points will not provide an increase in bandwidth availability.
What are two purposes of launching a reconnaissance attack on a network? (Choose two.)
to scan for accessibility
to retrieve and modify data
to gather information about the network and devices
to prevent other users from accessing the system
to escalate access privileges
to scan for accessibility
to gather information about the network and devices
Explanation: Gathering information about a network and scanning for access is a reconnaissance attack. Preventing other users from accessing a system is a denial of service attack. Attempting to retrieve and modify data, and attempting to escalate access privileges are types of access attacks.
A group of users on the same network are all complaining about their computers running slowly. After investigating, the technician determines that these computers are part of a zombie network. Which type of malware is used to control these computers?
botnet
spyware
virus
rootkit
botnet
Explanation: A botnet is a network of infected computers called a zombie network. The computers are controlled by a hacker and are used to attack other computers or to steal data.
An ACL is applied inbound on a router interface. The ACL consists of a single entry:
access-list 101 permit tcp 10.1.1.0 0.0.0.255 host 192.31.7.45 eq dns .
If a packet with a source address of 10.1.1.201, a destination address of 192.31.7.45, and a protocol of 23 is received on the interface, is the packet permitted or denied?
permitted
denied
denied
Refer to the exhibit. From which location did this router load the IOS?
flash memory
NVRAM?
RAM
ROM
a TFTP server?
flash memory
Refer to the exhibit. Which data format is used to represent the data for network automation applications?
XML
YAML
HTML
JSON
Explanation: The common data formats that are used in many applications including network automation and programmability are as follows:
JavaScript Object Notation (JSON) – In JSON, the data known as an object is one or more key/value pairs enclosed in braces { }. Keys must be strings within double quotation marks ” “. Keys and values are separated by a colon.
eXtensible Markup Language (XML) – In XML, the data is enclosed within a related set of tags <tag>data</tag>.
YAML Ain’t Markup Language (YAML) – In YAML, the data known as an object is one or more key value pairs. Key value pairs are separated by a colon without the use of quotation marks. YAML uses indentation to define its structure, without the use of brackets or commas.
JSON
Explanation: The common data formats that are used in many applications including network automation and programmability are as follows:
JavaScript Object Notation (JSON) – In JSON, the data known as an object is one or more key/value pairs enclosed in braces { }. Keys must be strings within double quotation marks ” “. Keys and values are separated by a colon.
eXtensible Markup Language (XML) – In XML, the data is enclosed within a related set of tags <tag>data</tag>.
YAML Ain’t Markup Language (YAML) – In YAML, the data known as an object is one or more key value pairs. Key value pairs are separated by a colon without the use of quotation marks. YAML uses indentation to define its structure, without the use of brackets or commas.
What QoS step must occur before packets can be marked?
classifying
shaping
queuing
policing
Classifying
What is the main function of a hypervisor?
It is used to create and manage multiple VM instances on a host machine.
It is a device that filters and checks security credentials.
It is a device that synchronizes a group of sensors.
It is software used to coordinate and prepare data for analysis.
It is used by ISPs to monitor cloud computing resources.
Explanation: A hypervisor is a key component of virtualization. A hypervisor is often software-based and is used to create and manage multiple VM instances.
It is used to create and manage multiple VM instances on a host machine.
Explanation: A hypervisor is a key component of virtualization. A hypervisor is often software-based and is used to create and manage multiple VM instances.
A company needs to interconnect several branch offices across a metropolitan area. The network engineer is seeking a solution that provides high-speed converged traffic, including voice, video, and data on the same network infrastructure. The company also wants easy integration to their existing LAN infrastructure in their office locations. Which technology should be recommended?
Frame Relay
Ethernet WAN
VSAT
ISDN
Ethernet WAN
Explanation: Ethernet WAN uses many Ethernet standards and it connects easily to existing Ethernet LANs. It provides a switched, high-bandwidth Layer 2 network capable of managing data, voice, and video all on the same infrastructure. ISDN, while capable of supporting both voice and data, does not provide high bandwidth. VSAT uses satellite connectivity to establish a private WAN connection but with relatively low bandwidth. Use of VSAT, ISDN, and Frame Relay require specific network devices for the WAN connection and data conversion between LAN and WAN.
Refer to the exhibit. As traffic is forwarded out an egress interface with QoS treatment, which congestion avoidance technique is used?
traffic shaping
weighted random early detection
classification and marking
traffic policing
traffic policing
Explanation: Traffic shaping buffers excess packets in a queue and then forwards the traffic over increments of time, which creates a smoothed packet output rate. Traffic policing drops traffic when the amount of traffic reaches a configured maximum rate, which creates an output rate that appears as a saw-tooth with crests and troughs.
An ACL is applied inbound on a router interface. The ACL consists of a single entry:
access-list 101 permit tcp 10.1.1.0 0.0.0.255 host 10.1.3.8 eq dns .
If a packet with a source address of 10.1.3.8, a destination address of 10.10.3.8, and a protocol of 53 is received on the interface, is the packet permitted or denied?
denied
permitted
denied
- Refer to the exhibit. What is the purpose of the command marked with an arrow shown in the partial configuration output of a Cisco broadband router?
defines which addresses are allowed into the router
defines which addresses can be translated
defines which addresses are assigned to a NAT pool
defines which addresses are allowed out of the router
defines which addresses can be translated
- If a router has two interfaces and is routing both IPv4 and IPv6 traffic, how many ACLs could be created and applied to it?
12
4
8
16
6
Explanation: In calculating how many ACLs can be configured, use the rule of “three Ps”: one ACL per protocol, per direction, per interface. In this case, 2 interfaces x 2 protocols x 2 directions yields 8 possible ACLs.
8
Explanation: In calculating how many ACLs can be configured, use the rule of “three Ps”: one ACL per protocol, per direction, per interface. In this case, 2 interfaces x 2 protocols x 2 directions yields 8 possible ACLs.
