2023年最新のECP-206試験問題集で最近更新された62問題 [Q30-Q50]

2023年最新のECP-206試験問題集で最近更新された62問題

Ericsson ECP-206リアル2023年最新のブレーン問題集で模擬試験問題集

質問 # 30
Which operating system is used in Ericsson Router 6000 products?

• A. SE-OS
• B. Junos
• C. ERS
• D. ERS
• E. IPOS

正解：C

解説：
Explanation
The operating system used in Ericsson Router 6000 products is ERS (Ericsson Router Software). ERS is based on IPOS (IP Operating System), which is a common operating system for Ericsson's IP portfolio. ERS provides advanced features and functionality for IP transport, such as MPLS, Segment Routing, QoS, IPSec, synchronization, SDN, and more. ERS also supports seamless integration with Ericsson Radio System and Ericsson Network Manager.
References: Router 6000 Series - Ericsson, Router 6675 Datasheet - Winncom

質問 # 31
Which protocol would be used to bundle multiple Ethernet ports into a virtual link with an aggregated bandwidth?

• A. RSTP
• B. LACP
• C. ERP
• D. VRRP

正解：B

解説：
Explanation
The protocol that would be used to bundle multiple Ethernet ports into a virtual link with an aggregated bandwidth is LACP, which stands for Link Aggregation Control Protocol. LACP is a protocol that allows two or more devices to negotiate the formation of a link aggregation group (LAG), also known as an EtherChannel or a port channel. A LAG combines multiple physical links into one logical link that provides increased bandwidth, load balancing, and redundancy. LACP is defined in IEEE 802.3ad and 802.1AX standards12.
References: Link Aggregation Control Protocol - Wikipedia, What is "link aggregation" and how does it benefit your network? | PC Gamer

質問 # 32
Review the exhibit.

A service provider wants to provide L3VPN for two customers (indicated by red and green in the exhibit).
Referring to the exhibit, which statement is correct?

• A. MP-BGP should be configured on all the service provider's routers (Ps and PEs).
• B. The service provider's P routers are not aware of the customers' routes.
• C. The two customers cannot use overlapping IP prefixes.
• D. LDP must be configured between PE and CE

正解：B

解説：
Explanation
Referring to the exhibit, the correct statement is that the service provider's P routers are not aware of the customers' routes. This is because P routers only need to forward MPLS packets based on their labels, without looking into their IP headers or VPN information. The P routers do not have any VRFs configured for the customers, nor do they participate in MP-BGP sessions with other PE routers. The PE routers are responsible for maintaining VRFs for each customer and for exchanging VPN routes with other PE routers using MP-BGP910.
References: Layer 3 VPNs (L3VPN) - Cisco, MPLS VPN - Wikipedia

質問 # 33
Review the exhibit.

In the exhibit, which action is performed by router R4?

• A. swap
• B. PHP
• C. pop
• D. push

正解：A

解説：
Explanation
In the exhibit, router R4 is performing a swap action. This means that router R4 is replacing the incoming label with a new label and forwarding the packet to the next hop along the LSP. In this case, router R4 receives a packet with label 20 from router R3 and swaps it with label 30 before sending it to router R5.
The exhibit shows an example of an MPLS network with four routers: R1, R2, R3, and R4. Router R1 is the ingress PE router and router R4 is the egress PE router. Router R2 and R3 are P routers. Router R1 assigns label 10 to the packet and sends it to router R2. Router R2 swaps label 10 with label 20 and sends it to router R3. Router R3 swaps label 20 with label 30 and sends it to router R4. Router R4 removes label 30 from the packet and forwards it based on its IP header or another label in the stack.
Therefore, the answer is D.
References: MPLS Label Switching | MPLS Operation | Push, Swap,Push IPCisco, A Complete Guide to Multiprotocol Label Switching (MPLS) - G2, Multiprotocol Label Switching - Wikipedia

質問 # 34
In your network, video traffic is being marked with DSCP code AF31.
Based on industry standard practice, which code would you use to assign higher priority to VoIP traffic?

• A. DF
• B. EF
• C. AF21
• D. AF11

正解：B

解説：
Explanation
The code that is commonly used to assign higher priority to VoIP traffic is EF, which stands for Expedited Forwarding. EF is a per-hop behavior (PHB) defined by the Differentiated Services (DiffServ) model for QoS.
EF provides low delay, low jitter, and low loss for real-time applications such as VoIP. EF is marked by setting the DSCP value to 101110, which corresponds to decimal 4678. AF31, which stands for Assured Forwarding class 3 low drop probability, is another PHB defined by DiffServ, but it provides lower priority than EF. AF31 is marked by setting the DSCP value to 011010, which corresponds to decimal 2678. DF, which stands for Default Forwarding, is a PHB defined by DiffServ that provides best-effort service for unmarked traffic. DF is marked by setting the DSCP value to 000000, which corresponds to decimal 078.
AF11, which stands for Assured Forwarding class 1 low drop probability, is another PHB defined by DiffServ, but it provides lower priority than EF and AF31. AF11 is marked by setting the DSCP value to 001010, which corresponds to decimal 1078.
References: Differentiated services - Wikipedia, Solved: Cisco VoIP Phone traffic marking - Cisco Community

質問 # 35
What are two roles of the DHCP protocol in a network? (Choose two.)

• A. It provides the authorization function to the network.
• B. It is used by hosts to obtain the IP address and other parameters from the DHCP server.
• C. It provides information about the number of hops between the source and the destination.
• D. It is used to inform hosts about the default gateway.

正解：B、D

解説：
Explanation
Two roles of the DHCP protocol in a network are:
It is used by hosts to obtain the IP address and other parameters from the DHCP server. DHCP stands for Dynamic Host Configuration Protocol, which is a protocol that provides automatic and centralized management of IP addresses and other network configuration parameters for devices connected to a network. A host that needs an IP address can send a request to a DHCP server, which will assign an available IP address from a pool and lease it to the host for a certain period of time34.
It is used to inform hosts about the default gateway. The default gateway is the IP address of the router that connects the host to other networks. The default gateway is one of the parameters that can be delivered by the DHCP server to the host, along with other parameters such as subnet mask, DNS server, domain name, etc. The host can use the default gateway to send packets to destinations outside of its local network34.
References: What Is DHCP? (Dynamic Host Configuration Protocol) - Lifewire, Dynamic Host Configuration Protocol - Wikipedia

質問 # 36
How do peers recognize each other's ability to use MP-BGP extensions?

• A. They advertise the ability using the capabilities field during the session establishment.
• B. They advertise the ability using the capabilities field in the hello packet.
• C. They advertise the ability using the capabilities field in the End-of-RIB marker.
• D. They advertise the ability using the capabilities field in the update packet.

正解：A

解説：
Explanation
Peers recognize each other's ability to use MP-BGP extensions by advertising the ability using the capabilities field during the session establishment. MP-BGP is an extension to BGP that allows BGP to carry routing information for multiple network layer protocols, such as IPv6, VPNv4, multicast, etc. To support MP-BGP, peers need to exchange their capabilities during the session establishment phase, which consists of three steps:
open, keepalive, and update. In the open message, peers can include an optional parameter called capabilities, which indicates what kind of address families and subsequent address families they can support. If both peers agree on a common set of capabilities, they can proceed to exchange routing information for those address families using update messages56.
References: Use of MP-BGP Extensions for IPv6 Interdomain Routing, MP-EBGP Configuration Example - Cisco

質問 # 37
Regarding the BGP decision algorithm, which two statements are correct? (Choose two.)

• A. A higher local-preference attribute will be favored over a lower local-preference attribute.
• B. A path cannot be considered if the next-hop is inaccessible.
• C. A lower local-preference attribute will be favored over a higher local-preference attribute.
• D. The most important criteria is the administrative distance.

正解：A、B

解説：
Explanation
Regarding the BGP decision algorithm, two statements that are correct are:
A higher local-preference attribute will be favored over a lower local-preference attribute. The local-preference attribute is used by BGP routers within an AS to indicate their preference for an exit point from the AS. A higher value means a more preferred path. The local-preference attribute is exchanged only between iBGP peers and does not leave the AS boundary89.
A path cannot be considered if the next-hop is inaccessible. The next-hop attribute is used by BGP routers to determine where to forward packets for a given destination prefix. The next-hop attribute is usually set to the IP address of the eBGP neighbor that advertises the prefix. If there is no IGP route to reach the next-hop address, the path is marked as invalid and ignored by BGP1011.
The other two statements are incorrect because:
The most important criteria is not the administrative distance, but rather the weight attribute. The administrative distance is used by routers to choose between routes from different routing protocols, not within BGP. The weight attribute is a Cisco-specific attribute that is used by BGP routers to prefer one path over another within the same router. The weight attribute is local to the router and not advertised to any peers1213.
A lower local-preference attribute will not be favored over a higher local-preference attribute, as explained above.
References: BGP Best Path Selection Algorithm - Cisco, Understanding BGP Local Preference Attribute - NetworkLessons.com, BGP Next Hop Attribute Explained - NetworkLessons.com, BGP Next Hop Processing
- Cisco Press, BGP Weight Attribute Explained - NetworkLessons.com, Understanding BGP Weight Attribute
- Cisco Community

質問 # 38
Which two statements are true about router node hardening? (Choose two.)

• A. LDAP, using the TLS protocol, should be implemented for remote logging.
• B. IPsec should be implemented to secure IGP routing protocols.
• C. Any unnecessary services should be disabled within each context.
• D. Enabling syslog ensures system events are logged to a remote server.

正解：C、D

解説：
Explanation
Two statements that are true about router node hardening are:
Any unnecessary services should be disabled within each context. Router node hardening is a process of securing a router from unauthorized access and attacks by applying various configurations and policies.
One of these configurations is to disable any services that are not needed for the router's functionality or purpose, such as telnet, ftp, http, etc. This reduces the attack surface of the router and prevents potential exploits of these services91.
Enabling syslog ensures system events are logged to a remote server. Syslog is a protocol that allows a router to send system messages and events to a remote server for logging and analysis. By enabling syslog on a router, network administrators can monitor the router's activity and performance, troubleshoot problems, detect anomalies, and audit security events101.
References: Cisco Router Hardening Step-by-Step | SANS Institute, Security Hardening Checklist Guide for Cisco Routers/Switches in 10 Steps, CCNA SEC: Router Hardening - Cisco Press

質問 # 39
P routers forward packets based on the ______.

• A. inner label
• B. LSP label
• C. flow label
• D. VPN label

正解：B

解説：
Explanation
P routers forward packets based on the LSP label. The LSP label is the label that corresponds to the label-switched path (LSP) that is established between two PE routers in an MPLS network. The LSP label is also called the outer label or the transport label, because it is used to transport packets across the MPLS core network. P routers are also called LSRs (label switch routers) or transit routers, because they switch packets based on their labels or remove the labels. P routers do not need to look at the IP header or any other information in the packet, except for the top label in the label stack. P routers perform one of three possible operations on labels: swap, pop, or PHP (penultimate hop popping). In a swap operation, the label is swapped with a new label, and the packet is forwarded along the path associated with the new label. In a pop operation, the label is removed from the packet, and the packet is forwarded based on its IP header or another label in the stack. In a PHP operation, the label is removed from the packet at the last P router before reaching the egress PE router, and the packet is forwarded without any label to the egress PE router.
The LSP label is different from other types of labels that may be used in MPLS networks, such as VPN labels or service labels. These labels are used to identify different VPNs or services that run over MPLS networks, such as Layer 2 VPNs, Layer 3 VPNs, traffic engineering, or QoS. These labels are also called inner labels or payload labels, because they are related to the payload of the packet. These labels are not used by P routers for forwarding decisions, but only by PE routers for delivering packets to their destinations.
Therefore, the answer is C.
References: Ericsson IP Networking - Routing Protocols, MPLS Fundamentals: Forwarding Labeled Packets - Cisco Press, MPLS Labels and Devices - NetworkLessons.com, Multiprotocol Label Switching - Wikipedia, VPN Packet Forwarding > MPLS/VPN Architecture Overview | Cisco Press, Basic concepts - Hewlett Packard Enterprise

質問 # 40
Which device will fragment IPv6 packets?

• A. firewall
• B. destination host
• C. router
• D. source host

正解：D

解説：
Explanation
The device that will fragment IPv6 packets is the source host. Fragmentation is a process of dividing a large packet into smaller pieces that can fit the maximum transmission unit (MTU) of the network link. In IPv4, fragmentation can be performed by either the source host or any intermediate router along the path. However, in IPv6, fragmentation is only allowed at the source host, and routers are not allowed to fragment packets. This reduces the processing overhead and complexity at routers and avoids potential fragmentation attacks. If a router receives an IPv6 packet that is too large for the next-hop link, it will drop the packet and send an ICMPv6 Packet Too Big message back to the source host56.
References: IPv6 address - Wikipedia, IPv6 Fragmentation - Cisco

質問 # 41
Which statement is true about LDP?

• A. LDP relies on IGP for all routing-related decisions.
• B. LDP and IGP both exchange their databases every 60 seconds.
• C. LDP performs routing functions along with IGP.
• D. LDP and IGP both exchange their databases every 30 seconds.

正解：A

解説：
Explanation
LDP relies on IGP for all routing-related decisions. LDP is a protocol that distributes labels in an MPLS environment, but it does not perform any routing functions. LDP uses the underlying routing information provided by an IGP, such as OSPF or IS-IS, to forward label packets. LDP and IGP do not exchange their databases at regular intervals, but rather use hello messages to maintain adjacencies and sessions. References: Ericsson IP Networking - Routing Protocols, Label Distribution Protocol - Wikipedia

質問 # 42
Which two statements are true about route summarization? (Choose two.)

• A. It improves the best route calculation.
• B. It reduces signaling.
• C. It reduces the size of a routing table.
• D. It summaries the routing table entries into a default route

正解：B、C

解説：
Explanation
Route summarization is a technique that reduces the number of routes that a router advertises to its neighbors by creating a single summary route that covers multiple subnets or networks. Route summarization has several benefits, such as:
It reduces the size of a routing table, which saves memory and CPU resources on the router. A smaller routing table also improves the lookup efficiency and convergence time of the routing protocol.
It reduces signaling, which means that less bandwidth is consumed by routing updates and less processing is required by neighboring routers. This also enhances the stability and scalability of the network, as fewer routing changes are propagated.
It improves route aggregation, which means that more specific routes are replaced by a less specific route that can be advertised to other autonomous systems or routing domains. This simplifies the inter-domain routing and hides the internal topology details.
Route summarization does not necessarily summarize the routing table entries into a default route, although a default route can be considered a special case of route summarization where all destinations are covered by one route. Route summarization also does not improve the best route calculation, as it may introduce suboptimal routing or black holes if not done properly. : Introduction to Route Summarization - NetworkLessons.com, Route Summarization > Example for Understanding Route Summarization - Cisco Press

質問 # 43
Which protocol would be used to bundle multiple Ethernet ports into a virtual link with an aggregated bandwidth?

• A. RSTP
• B. LACP
• C. ERP
• D. VRRP

正解：B

解説：
Explanation
The protocol that would be used to bundle multiple Ethernet ports into a virtual link with an aggregated bandwidth is LACP, which stands for Link Aggregation Control Protocol. LACP is a protocol that allows two or more devices to negotiate the formation of a link aggregation group (LAG), also known as an EtherChannel or a port channel. A LAG combines multiple physical links into one logical link that provides increased bandwidth, load balancing, and redundancy. LACP is defined in IEEE 802.3ad and 802.1AX standards12.
References: Link Aggregation Control Protocol - Wikipedia, What is "link aggregation" and how does it benefit your network? | PC Gamer

質問 # 44
Within an IGP area, which two statements are correct? (Choose two.)

• A. Routers summarize information they learn from neighbors.
• B. Routers relay information delivered by neighbors.
• C. Routers discard valid but inaccurate information from neighbors.
• D. Routers advertise information about themselves.

正解：B、D

解説：
Explanation
Within an IGP area, routers advertise information about themselves and relay information delivered by neighbors. This is how link-state routing protocols such as OSPF and IS-IS work. They flood information about the network topology to all routers in the same area or domain. That information is then used to build a complete network connectivity map and to calculate the shortest path to destinations. Routers do not summarize or discard information within an area, unless they are configured to do so by some filtering mechanism. References: Ericsson IP Networking - Routing Protocols, IP Routing: ISIS Configuration Guide - IS-IS Overview and Basic Configuration

質問 # 45
Which conceptual table created by routing protocols is used when processing an IP packet?

• A. forwarding information base
• B. management information base
• C. traffic engineering data base
• D. label information base

正解：A

解説：
Explanation
The conceptual table created by routing protocols that is used when processing an IP packet is the forwarding information base (FIB). The FIB is a table that contains the bestroutes to reach each destination network prefix, along with the outgoing interface and the next-hop address for each route. The FIB is derived from the routing information base (RIB), which is a table that contains all the routes learned from different routing protocols and sources. The FIB is used by the router to make fast forwarding decisions for each incoming packet, based on its destination address12.
References: Security Hardening Checklist Guide for Cisco Routers/Switches in 10 Steps, VLAN - Wikipedia

質問 # 46
IPv6 link-local addresses are designed to be used in which three situations? (Choose three.)

• A. for neighbor discovery
• B. for local IP communication on the IPv6 capable routers
• C. by routers to forward packets with link-local source addresses to other links
• D. addressing on a single link for purposes such as auto-address configuration
• E. when routers are not present

正解：A、B、D

解説：
Explanation
IPv6 link-local addresses are designed to be used in three situations: for neighbor discovery, for local IP communication on the IPv6 capable routers, and for addressing on a single link for purposes such as auto-address configuration. Neighbor discovery is a protocol that allows IPv6 nodes to discover each other and learn their link-layer addresses on a local network. Neighbor discovery uses link-local addresses to send and receive messages such as router advertisements, router solicitations, neighbor advertisements, and neighbor solicitations34. Local IP communication on the IPv6 capable routers refers to the ability of routers to exchange routing information or management traffic using their link-local addresses as source and destination addresses. This reduces the need for global unicast addresses on router interfaces that are not reachable from outside the local network35. Addressing on a single link for purposes such as auto-address configuration refers to the use of link-local addresses to enable IPv6 nodes to obtain an address without manual configuration or a DHCP server. Link-local addresses can be automatically derived from the interface identifier in the modified EUI-64 format or randomly generated. Link-local addresses can also be used to test the connectivity of a link before obtaining a global unicast address36.
References: Understand the IPv6 Link-Local Address - Cisco, Link Local Address - GeeksforGeeks, IPv6 Address Types | Link-Local, Global Unicast, etc. IPCisco, MPLS Label Distribution Protocol Commands - Cisco

質問 # 47
For IP destinations not found in the IS-IS Level 1 database, the Level 1 router must forward packets to the nearest Level 1-Level 2 router with which set?

• A. attach bit
• B. status bit
• C. overload bit
• D. options bit

正解：A

解説：
Explanation
For IP destinations not found in the IS-IS Level 1 database, the Level 1 router must forward packets to the nearest Level 1-Level 2 router with the attach bit set. The attach bit is a flag in the IS-IS Level 1 LSP that indicates that the router is also a Level 2 router and can reach destinations outside the Level 1 area. The Level
1 router will install a default route pointing to the nearest Level 1-Level 2 router with the attach bit set. This way, the Level 1 router can forward packets to other areas without having to maintain a full Level 2 database. References: Ericsson IP Networking - Routing Protocols, Configure Attach Bit Set - Cisco

質問 # 48
What does an LDP implicit null label cause?

• A. forwarding the packet unchanged
• B. penultimate hop popping by an upstream router
• C. penultimate hop popping by a downstream router
• D. swapping with a new label

正解：C

解説：
Explanation
An LDP implicit null label causes penultimate hop popping by a downstream router. LDP is a protocol that distributes labels for MPLS forwarding along the shortest path calculated by an IGP. An implicit null label is a special label value of 3 that indicates that the downstream router does not need a label to forward the packet to its destination. When an upstream router receives an implicit null label from a downstream router, it removes (or pops) the label from the packet before sending it to the downstream router. This process is called penultimate hop popping (PHP) and it reduces the load on the downstream router, which can forward the packet based on its IP header or another label in the stack59.
References: MPLS Label Distribution Protocol Commands - Cisco, Solved: Implicit null and Explicit null - Cisco Community

質問 # 49
Which two statements are true regarding the LSP? (Choose two.)

• A. The LSP refers to a specific label assigned to a packet by the LSR for a destination.
• B. The LSP refers to a sequence of routers that add. remove, or change label values along the path.
• C. The LSP refers to a sequence of routers that forward the MPLS packet based on labels.
• D. The LSP refers to a sequence of routers that add, remove, or change label values based on the destination MAC address.

正解：B、C

解説：
Explanation
Two statements that are true regarding the LSP are:
The LSP refers to a sequence of routers that forward the MPLS packet based on labels. An LSP is a Label Switched Path, which is a path through an MPLS network that is established by signaling protocols such as LDP or RSVP-TE. An LSP consists of a sequence of routers (called Label Switching Routers or LSRs) that forward packets based on labels rather than IP addresses. Labels are short fixed-length identifiers that are attached to packets at the ingress router and removed at the egress router. Labels can be swapped or popped at intermediate routers according to their label forwarding tables78.
The LSP refers to a sequence of routers that add, remove, or change label values along the path. As mentioned above, an LSP consists of a sequence of routers that forward packets based on labels. Along the path, different routers may perform different operations on the labels depending on their role and configuration. The ingress router adds one or more labels to the packet before sending it into the MPLS network. The egress router removes all labels from the packet before sending it out of the MPLS network. The intermediate routers may swap one label with another label according to their label forwarding tables. This process is called label switching78.
References: MPLS Fundamentals: 3 - MPLS Packet Forwarding, Multiprotocol Label Switching - Wikipedia

質問 # 50
......

厳密検証されたECP-206試験問題集と解答で無料提供のECP-206問題と正解付き：https://jp.fast2test.com/ECP-206-premium-file.html