Cisco 350-501 Dumps

• In Cisco Unified MPLS, BGP (Border Gateway Protocol) is used to transport labels along with network layer reachability information. RFC 3107 defines BGP/MPLS IP Virtual Private Networks (VPNs) and allows BGP to carry MPLS labels, enhancing scalability and flexibility in MPLS networks.

References

1: Cisco. “Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR).” Link

Router 1 is the trigger router in a Remote Triggered Black Hole (RTBH) implementation. In the configuration provided, Router 1 has a static route to null0 for network 192.168.1.0/24 with a tag of 1, which is used to drop traffic destined to this network, effectively mitigating DDoS attacks. The route-map “ddos” matches this tag and sets local preference and community accordingly. The BGP process redistributes this static route based on the “ddos” route-map, signaling other routers in the network to drop traffic destined for the attacked network. References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - RTBH section1.

The Adjacency-SID sub-TLV extension is advertised within TLV-22 (Extended IS Reachability) to label a specific link in a segment routing domain. This allows for the identification and utilization of specific paths or links within the network, facilitating more efficient routing and traffic management. References := Implementing and Operating Cisco Service Provider Network Core Technologies

In the Pipe model of MPLS QoS, the MPLS EXP bits are set by the Customer Edge (CE) device. This model allows the CE to mark the packets, and these markings are retained throughout the MPLS network until they reach the egress Provider Edge (PE) router. The PE router does not alter the MPLS EXP value, ensuring that the QoS policy applied by the customer is preserved end-to-end.

References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR)

The correct configuration to apply to the ASN 65001 border router is Option C. This configuration uses a route policy named PEER-AS65002-IN, which is applied to incoming routes from ASN 65002. The policy denies routes that have traversed 10 or more ASNs or have looped through ASN 65001. It also assigns a community value of 65001:200 to routes matching the prefix 2001:db8:aaaa::/48, which aligns with the conditions specified.

References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR v1.0); Cisco SPCOR Training & Certification.

The issue is occurring in OSPF stub area 100 where the Ethernet link is down between routers RX and RY due to a cut fiber, leading to dropped traffic from CE site A to the hub site. Changing the OSPF area 100 type to stub on RZ can resolve these issues. In a stub area, OSPF routers use a default route to forward traffic to destinations outside the area, reducing the size of their routing tables. This would allow traffic from CE site A to be routed through RZ when the direct link between RX and RY is down.

References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - Cisco SPCOR Training

 Both Chef and Puppet are configuration management platforms that aim to configure and manage servers and other IT infrastructure. They operate in the same infrastructure management space and share several similarities:

• Use a master-client architecture: Chef functions with a master-client architecture, where the server runs on the master machine, and the client runs as an agent on every client machine. Similarly, Puppet follows a similar setup.
• Manage devices or nodes to be configured: Both Chef and Puppet manage the configuration of devices or nodes within an infrastructure.
• Leverage a pull model: Both tools use a pull model, where the configuration is pulled from a central server to the managed nodes.

The configuration shown indicates that Router 1 is set up with a route-map named “ddos” that matches traffic tagged with “tag 1”. The traffic matching this tag is then set to have a next-hop IP of 192.0.2.1 and a local preference of 150. The community is also set to “no export”, which means this route will not be advertised to external BGP peers. Since there’s no explicit deny statement in the configuration, only traffic with tag 1 and local preference of 150 will be dropped by Router 1 as per the BGP routing policy. References: Implementing and Operating Cisco Service Provider Network Core Technologies course materials. 

In the context of OSPF multiarea implementation, adjacency issues can often be resolved by specifying the type of network on the interface. In this case, option B “ip ospf network point-to-point” is appropriate as it helps in forming OSPF adjacency over point-to-point links by allowing OSPF to use a simpler neighbor discovery process, which can resolve adjacency issues. References := Implementing and Operating Cisco Service Provider Network Core Technologies

 RFC 5305 extends the IS-IS protocol for traffic engineering by specifying new information that an Intermediate System (router) can place in Link State Protocol Data Units (LSPs). Sub-TLV type 10 of the extended IS-IS reachability TLV type 22 is used to specify the maximum reservable link bandwidth. This is an important parameter for traffic engineering as it defines the amount of bandwidth that can be reserved by traffic engineering algorithms for use in constrained-path computations for MPLS traffic engineering Label Switched Paths (LSPs). References: RFC 53051.

The correct configuration for enabling BGP FlowSpec client function and installation of policies on all local interfaces is flowspec address-family ipv4 install interface-all local. This command configures the router to accept FlowSpec policies from a BGP peer and apply them to all local interfaces. The flowspec keyword enables the BGP FlowSpec client function, address-family ipv4 specifies the address family, and install interface-all local ensures that the policies are installed on all local interfaces. References := Implementing and Operating Cisco Service Provider Network Core Technologies course.

RSVP (Resource Reservation Protocol) is used with MPLS (Multiprotocol Label Switching) traffic engineering tunnels primarily to reserve bandwidth along the path of the tunnel. This ensures that sufficient resources are allocated for the traffic to meet quality of service requirements, which is crucial for maintaining the performance of critical applications that traverse the network. References := For more information on RSVP and MPLS traffic engineering, refer to the Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course materials, which provide detailed explanations on how these technologies work together to optimize network traffic1.

Flexible NetFlow improves on traditional NetFlow by providing more flexibility and efficiency in collecting and analyzing network flow data. In this specific configuration, the “mode random one-out-of-100” command is used, which means that only one out of every 100 packets is sampled. This leads to reduced CPU and memory utilization (Option A) because fewer packets are being processed. Additionally, because fewer packets are being analyzed (only one out of every 100), the number of packets to be analyzed is significantly reduced (Option D), leading to further efficiencies.

References :=

• Implementing and Operating Cisco Service Provider Network Core Technologies
• On-Demand E-Learning

 In IS-IS, Level 2 peers must have matching authentication settings to ensure security and integrity of the routing domain. The hello timer setting must also match to ensure that the peers can maintain a consistent adjacency state. Mismatched hello timers could lead to adjacency flaps or failure to form an adjacency.

References: The information is based on the IS-IS protocol’s use of TLVs (Type-Length-Value) which makes it highly extensible. As new features come in, they can be added to the protocol with TLVs. This includes authentication mechanisms and timer settings that ensure secure and stable adjacencies between Level 2 peers

 In BGP, the Local Preference attribute is used to influence the exit point from an AS (Autonomous System). A higher local preference value is preferred, and all routes received inherit the local preference value of the route that is installed in the IP routing table. So, configuring a higher local preference outbound will make specific BGP speakers as preferred exit points for customer AS. References := Cisco

 In Cisco IOS XR software, the keychain management for BGP is done in the routing configuration mode. This mode allows you to configure keychain parameters such as the key identifier, cryptographic algorithm, and other related settings. The keychain is essential for authentication and secure communication between BGP peers. By configuring the keychain in the routing context, you ensure that BGP sessions use the specified keys for authentication and integrity protection1.

References:

• Implementing Keychain Management - Cisco IOS XR Routing Configuration Guide
• BGP Configuration Guide for Cisco NCS 540 Series Routers, IOS XR Release 7.8.x - Master Key Tuple Configuration

 MPLS TE tunnels are designed to optimize the flow of network traffic by mapping it onto specific paths based on resource requirements. Two key characteristics of MPLS TE tunnels are:

• RSVP for Bandwidth Reservation: MPLS TE tunnels use the Resource Reservation Protocol (RSVP) to reserve the necessary bandwidth for the tunnel, ensuring that the required resources are available for the data that will flow through it12.
• Unidirectional Flow: These tunnels are unidirectional, meaning they are established from a source to a destination and do not inherently support traffic in the reverse direction. This is because each MPLS TE tunnel is associated with a label-switched path (LSP) that is specifically set up for traffic flowing in one direction

To enable LDP session protection for LDP neighbors within each VRF, the engineer should configure LDP session protection within the individual VRFs. This ensures that LDP sessions are protected at the VRF level, providing security and stability for MPLS-based services. By enabling LDP session protection within each VRF, the router will take appropriate actions to protect LDP sessions against misbehaving neighbors or potential attacks. References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) v1.0

The script in the exhibit is for configuring a static VLAN (Option D). The XML configuration specifies a static VLAN range with “allocMode=‘static’”, indicating that VLAN IDs are assigned manually, not dynamically.

References := These explanations are derived from the concepts outlined in the Cisco Service Provider source book, specifically the “Implementing and Operating Cisco Service Provider Network Core Technologies” course materials,

The Cisco MPLS TE forwarding adjacency feature allows a TE tunnel to be advertised into the IGP, effectively making the tunnel appear as a network link in the IGP topology. This integration helps in the optimal utilization of the TE tunnel by other routers for IP routing purposes.

In an EVPN operation, the PE (Provider Edge) router determines and advertises Ethernet segment reachability by discovering remote ESIs (Ethernet Segment Identifiers) and determining their redundancy mode (all-active or single-active). This is crucial in multihoming scenarios where the PE needs to auto-discover remote PEs and the corresponding redundancy mode. In case of segment failures, PEs withdraw the routes used at this stage to trigger fast convergence by signaling a MAC mass withdrawal on remote PEs3.

References:

• Cisco, “EVPN Configuration Guide for Cisco 8000 Series Routers, IOS XR Release 7.11.x”
• Huawei, “Overview of EVPN - New IP Technologies”

The command nsf ietf helper strict-lsa-checking is used to configure the router to terminate the OSPF graceful restart process if it detects any changes in the LSA during the restart. This ensures that the network remains stable and consistent by preventing the use of outdated or incorrect routing information.

 MPLS LDP (Label Distribution Protocol) is used for label distribution in MPLS networks. When making changes to the LDP configuration, it’s essential to ensure that the changes do not disrupt existing LDP sessions. In this scenario, the network administrator implemented MPLS LDP changes on the PE-A LSR (Label Switching Router) device, and the goal is to prevent any disruption to LDP peers.

The MPLS LDP Non-Stop Routing (NSR) feature allows LDP sessions to survive control-plane switchover events without interruption. When NSR is enabled, the LDP session state information is synchronized between the active and standby control planes. If the active control plane fails, the standby control plane takes over seamlessly, and LDP sessions continue without interruption.

• References:

 The issue likely lies in the customer platforms’ default policy, which restricts E-BGP route exchange. References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course materials.

• https://www.cisco.com/c/en/us/support/docs/mpls-vpns/multiprotocol-label-switching-mpls/23986-mpls-vpns-config-example.html
• https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/mp_l3_vpns/configuration/15-mt/mp-l3-vpns-15-mt-book/mp-bgp-mpls-vpns.html

To configure multi-topology IS-IS for IPv6, the router must be configured with the ipv6 router isis command under the interface configuration mode. This command enables IS-IS for IPv6 on the interface. The ipv6 router isis command is used to enable IS-IS for IPv6 on an interface. The multi-topology keyword specifies that the interface will participate in multiple topologies. The level-1 and level-2 keywords specify the IS-IS levels for which the interface will participate. In this case, we want the interface to participate in both Level 1 and Level 2 topologies, so we use both keywords. 

Path Computation Element (Calculates paths through the network, keeps TE topology database information, sends path status updates)

Path computation Client (sends path calculation request, sends path creation request)

Path Computation Element (PCE)

Represents a software module (which can be a component or application) that enables the router to compute paths applying a set of constraints between any pair of nodes within the router’s TE topology database. PCEs are discovered through IGP.

Path Computation Client (PCC)

Represents a software module running on a router that is capable of sending and receiving path computation requests and responses to and from PCEs. The PCC is typically an LSR (Label Switching Router).

re/crs_r5-3/mpls/configuration/guide/b-mpls-cg53x-crs/b-mpls-cg53x-crs_chapter_0110.html#con_1279822

SNMPv3 is the most secure version of SNMP, providing both security and remote configuration capabilities. The current configuration in the exhibit shows SNMP version 2c, which is less secure. SNMPv3 introduces security features such as authentication, privacy (encryption), and access control to address the vulnerabilities associated with earlier versions of SNMP. By re-configuring to use SNMPv3, the network administrator can enhance the security for SNMP for this configuration. References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - Cisco SPCOR Training & Certification

The issue here is that R1 and R2 cannot yet establish an LDP TCP connection. From the exhibit, it’s clear that the password is not required as it states “Password: not required, none, in use”. So, option C “Configure the no mpls Idp password option 1 command on R2” would be the correct answer to allow the establishment of an LDP TCP connection without requiring a password. This aligns with Cisco’s guidelines on configuring MPLS LDP where passwords might not be necessary for establishing connections between routers.

References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - Cisco SPCOR

 The issue described involves packets being dropped when sent from the application server to the access site. Since OSPF and BGP peerings are confirmed to be operational, the problem likely lies within the route advertisement. Allowing 172.16.20.1 in the BGP advertisement on R3 by adjusting the route-map will likely resolve the issue, ensuring that traffic destined for 172.16.20.1 is not being inadvertently filtered or blocked.

References:

• Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course provides insights into configuring, verifying, troubleshooting, and optimizing Service Provider IP network infrastructures, which includes understanding and implementing BGP routing and route maps1.
• The official Cisco certification exam overview for SPCOR, which includes topics on BGP routing and route maps, can also serve as a reference

 To establish LDP peering with the loopback IP address as its Router ID, both RA and RC need to configure their LDP router IDs to use their respective loopback addresses. This is done by applying the ‘mpls ldp router-id loopback0’ command on both routers. This configuration ensures that LDP peering uses the loopback addresses, which is a requirement for the service-provider core network.

References := This explanation is based on the concepts outlined in Cisco’s Implementing and Operating Service Provider Network Core Technologies (SPCOR) course, which provides in-depth knowledge on service provider infrastructure. For further study, refer to the official Cisco documentation and training materials available on the Cisco Learning Network Store.

 In BGP, the weight attribute is the first criterion used to determine the best path. It is a Cisco-specific attribute and is not propagated in BGP updates. Weight is a numeric value, and the path with the highest weight is preferred. If weights are the same, BGP will then consider the local preference, AS path length, origin type, and other attributes in sequence.

References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) training material

The correct command to authenticate the OSPF neighbor between PE-A and PE-B using MD5 is found in Option A. In this option, the command ip ospf message-digest-key 1 md5 44578611 is used to configure OSPF MD5 authentication on an interface with the key ID as 1 and key string as 44578611. The second command ip ospf authentication key-chain 44578611 is used to enable OSPF authentication on an interface and associate it with a specific key chain. References := Cisco - Implementing and Operating Cisco Service Provider Network Core Technologies

Using verbose knob in above command will list all the hops as below: R1#traceroute mpls multipath ipv4 10.1.5.5 255.255.255.255 verbose

Here is the solution:

Text Description automatically generated

Remember that SSM is an extension of IP multicast where datagram traffic is forwarded only from explicitly joined multicast sources to receivers. It creates source-specific multicast distribution trees without shared trees.

References:

• Cisco PIM-SSM Configuration Example
• Cisco IP Multicast: PIM Configuration Guide

The primary role of a BR (Border Relay) router in a 6rd (IPv6 Rapid Deployment) environment is to connect the CE (Customer Equipment) routers with the IPv6 network. The BR router de-encapsulates IPv6 packets that are encapsulated in IPv4 packets from the CE routers and forwards them to the IPv6 internet. This process is stateless and allows for high availability and load balancing by potentially having more than one BR router configured with the same IPv4 address (anycast), so CE routers are routed to the closest BR router12.

References:

• NetworkLessons.com, “IPv6 6RD (Rapid Deployment)”
• RFC 5969, “IPv6 Rapid Deployment on IPv4 Infrastructures (6rd) – Protocol Specification”

The configuration ip verify unicast source reachable-via any under interface gigabitethernet0/1 on Router 1 ensures that incoming packets have a source IP address that matches an entry in the FIB (Forwarding Information Base), indicating it’s reachable via a real interface. This helps mitigate attacks by dropping traffic with unreachable source addresses. References := Cisco

The issue with establishing an IS-IS adjacency between the two routers stems from a mismatch in the configuration of their interfaces. Router R2’s interface is set to point-to-point, while the peer router interface is set to multipoint. For IS-IS adjacencies to form, both interfaces must be configured with the same network type. The discrepancy in the network types is preventing the adjacency from being established. To resolve this, the network operator must ensure that both interfaces are either configured as point-to-point or as multipoint. References := Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR)

 The configuration in the exhibit shows the implementation of Nonstop Forwarding (NSF) with OSPF. NSF is used to minimize the downtime of neighbor relationships during a Route Processor (RP) switchover. The nsf command enables NSF, and ietf specifies the use of the IETF standard for graceful restart in OSPF. The restart interval 90 sets the time, in seconds, within which the restarting router should complete its restart, helping to maintain uninterrupted forwarding despite the switchover.

References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR v1.0); Cisco SPCOR Training & Certification.

• References: Implementing and Operating Cisco Service Provider Network Core Technologies source documents or study guide.

When implementing LDP NSF on your network, enabling NSF for the link-state routing protocol in use on the network is essential to ensure continuous forwarding of packets during a failure scenario. Additionally, enabling NSF for BGP ensures that BGP sessions are not dropped during a switchover, maintaining network stability and uptime.

To ensure that critical, time-sensitive data from the server on R1 to the host on R3 is always prioritized, especially during congestion, the network engineer should implement a Quality of Service (QoS) strategy that uses strict priority queuing. This QoS mechanism ensures that traffic marked as high priority is transmitted first, while other traffic may be queued or dropped if necessary. Strict priority queuing is designed for scenarios exactly like this, where certain traffic must be guaranteed bandwidth to meet time-sensitive requirements. References := For more detailed information on QoS strategies and classification, refer to the Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course materials, specifically the sections discussing QoS mechanisms and their implementation in service provider networks. Additionally, Cisco’s official documentation on QoS provides comprehensive guidelines on configuring and applying strict priority queuing to ensure bandwidth for critical traffic.

The configuration snippet is for model-driven telemetry on Cisco IOS XR, which involves creating a sensor-group named “cisco” and specifying a YANG model path for telemetry data collection. This configuration is used to stream telemetry data from the router, aligning with option D. References: = Implementing and Operating Cisco Service Provider Network Core Technologies course materials

 In XML, a self-closing tag such as  indicates that the element does not contain any data, hence the data field is considered blank. This is a common way to represent empty elements in XML documents.

References: For further details, you can refer to XML-related sections in the Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) materials, which explain the structure and usage of XML in network configurations.

• The BGPsec framework is designed to secure the AS path information in BGP updates. It uses digital signatures to validate the AS path and prevent unauthorized route manipulation. Here are the key points related to BGPsec:

• Securing AS Path:
• Private Keys and Router Key Pair:
• Expiration Time:

In summary, BGPsec enhances BGP security by securing the AS path using digital signatures and private keys. It does not rely on IPsec tunnels for security1.

References:

• Cisco. (2021). Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) v1.0. Cisco Learning Services.
• Cisco. (2021). Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) v1.1. Cisco Learning Network Store.
• Cisco. (2021). BGPsec Overview. Link

The IPv4 address family configuration under neighbor configuration-mode must be removed. The exhibit shows the configuration of a BGP neighborship between an ASBR and a directly connected BGP speaker. The ASBR is running Cisco IOS XR. The neighbor is configured with the IPv4 address family, which is not supported on Cisco IOS XR. To establish the BGP neighborship, the IPv4 address family configuration must be removed.

In a multivendor network environment, it is essential to configure OSPF NSF with the IETF standard to ensure compatibility across different vendor devices. The command router ospf 1 nsf ietf enables OSPF NSF capability using the IETF standard, which facilitates uninterrupted forwarding during a route processor switchover.

References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - OSPF Nonstop Forwarding section.

 In the context of Implementing and Operating Cisco Service Provider Network Core Technologies, LDP-IGP Synchronization is configured to ensure that the IGP and LDP convergences are synchronized. Option C is correct because it shows the configuration where router ISIS 1 is being configured with MPLS LDP sync, but not on a specific interface, ensuring that LDP is operational on all interfaces where IS-IS is enabled before routes are advertised. References := Cisco

The configuration shown in the exhibit enables IP flow information collection on the interface gigabitethernet0/1. This setup is used for network traffic analysis, and when applied, it provides data that includes the source interface of the traffic for traceback analysis. This is useful for identifying the origin of traffic, which can be critical in situations such as security incidents or network troubleshooting.

References: The details for this configuration can be found in the Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course materials, which serve as a comprehensive guide for understanding and applying Cisco service provider technologies.

R1

router ospf 10

redistribute static

int et0/0

ip ospf hello-interval 5

ip ospf dead-interval 10

ip ospf cost 15

ip ospf 10 area 0

copy run start

R2

router ospf 10

redistribute static

int et0/0

ip ospf hello-interval 5

ip ospf dead-interval 10

ip ospf cost 15

ip ospf 10 area 0

copy run start

The Internet gateway router being connected as a PE router to the MPLS backbone is a design attribute that can be used to provide Internet access to a major customer through a separate dedicated VPN. This setup allows for efficient routing and separation of traffic, ensuring security and performance.

 The local-as keyword is used in BGP configurations to change the local AS number that is used in the BGP OPEN message when establishing a BGP session with a specific neighbor. In this case, even though the router is configured with AS 65000, it will use AS 65112 when establishing a connection with neighbor 192.168.1.2 due to the local-as keyword configuration. References := Cisco

 Cisco MPLS Traffic Engineering (TE) tunnels necessitate a link-state routing protocol like OSPF or IS-IS because these protocols use Shortest Path First (SPF) calculations. The tunnel endpoints leverage these SPF calculations to implement the tunnel, ensuring an efficient and optimized path through the network. This is essential for MPLS TE, which aims to optimize network resource utilization and improve traffic distribution across the network.

References: Cisco Community, Cisco Documentation

Cisco IOS XE Software is an open and flexible operating system optimized for a variety of network infrastructures. One of its key enhancements over Cisco IOS Software is the support for symmetric multiprocessing (SMP). This allows the operating system to efficiently utilize multiple CPU cores, improving performance and scalability for network services.

References: The enhancement details are derived from the Cisco IOS XE Software overview, which highlights its capabilities and benefits over the traditional Cisco IOS Software.

The correct configuration for deploying VRF on ASBR router R1 to have connectivity over an MPLS VPN inter-AS Option AB network is found in option C. This involves configuring the interface with the commands shown, including setting the interface ethernet, applying IP VRF forwarding, and enabling MPLS BGP forwarding. These steps ensure that the interface is properly configured for VRF and can support MPLS VPN inter-AS communications effectively. References := Implementing and Operating Cisco Service Provider Network Core Technologies

The OSPF adjacency issue between R1 and R2 is likely due to mismatched OSPF network types or hello/dead interval settings. The command ip ospf network point-to-point is used on point-to-point network types, which do not require matching hello/dead intervals, thus allowing OSPF adjacency to form even if these intervals are mismatched on the two routers. References: = Implementing and Operating Cisco Service Provider Network Core Technologies course materials. (

In MPLS Layer 3 VPNs, shared services such as Internet access can be provided through the use of a shared services VRF (Virtual Routing and Forwarding). The customer VRF uses route targets to import routes from the shared services VRF, which contains the routes to the Internet. This allows the customer sites to access the Internet without compromising the isolation of their private networks. References: The concept of shared services VRF and the use of route targets for importing and exporting routes are common practices in MPLS VPN implementations.

The issue described indicates that the preferred BGP path for traffic destined to 192.168.1.1/32 is not being used. By applying a route-map with a higher Local Preference (LP) on R1 for the prefix 192.168.1.1/32, the BGP path attributes can be manipulated to prefer the path through R2. Local Preference is a BGP attribute that determines the preferred exit path out of an AS. A higher Local Preference value is preferred over a lower one. Therefore, configuring the route-map High-LP with a higher Local Preference on R1’s BGP peering with R2 will influence the BGP path selection process, ensuring that traffic for 192.168.1.1/32 prefers the path R3-R2-R1 as expected.

References: The solution utilizes the BGP path selection process and the manipulation of BGP attributes, as taught in the Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course

Stateful (It has 1: N translation, It uses address overloading, It conservers IPv4 addresses)

Stateless (It is limited on the number of endpoints, It mandates IPv4-translatable IPv6 address allocation)

•  The PCE (Path Computation Element) communicates with the PCC (Path Computation Client) using the PCEP. PCEP is responsible for path computation and signaling in MPLS networks.
• References: Implementing and Operating Cisco Service Provider Network Core Technologies course materials.

The configuration command xconnect 192.168.0.1 12 encapsulation mpls pw-class cisco is used to set up a pseudowire connection to a remote peer at IP address 192.168.0.1 using MPLS encapsulation. The pw-class cisco refers to a pseudowire class named ‘cisco’ that defines the parameters for the MPLS pseudowire. This configuration is part of setting up Layer 2 VPNs, which are often used in service provider networks to extend services such as Ethernet, ATM, or Frame Relay over an MPLS network.

References: For more detailed information, please refer to the Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course materials, specifically the sections covering MPLS and Layer 2 VPNs.

• NetFlow provides traceback information by analyzing network traffic. To configure NetFlow for traceback, you need to set up a classification ACL (Access Control List) to identify which type of traffic will be analyzed. This allows NetFlow to focus on specific traffic flows and report relevant information. The classification ACL can be based on various criteria such as source/destination IP addresses, port numbers, or protocols. By defining the classification ACL, you ensure that only the relevant traffic is considered for NetFlow analysis.
• References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) v1.0

Diagram Description automatically generated

The correct configuration to reduce LDP LIB size and advertise label bindings for the /32 loopback IP space only is to use an IP prefix-list that specifies the /32 prefix length and then configure MPLS LDP to allocate labels for these prefixes. The ip prefix-list LOOPBACKS seq 5 permit 0.0.0.0/0 le 32 command creates a prefix-list named LOOPBACKS that allows any IP address with a prefix length less than or equal to 32. The mpls ldp label allocate global prefix-list LOOPBACKS command then instructs the router to allocate labels for all prefixes permitted by the LOOPBACKS prefix-list, which in this case, would be all /32 prefixes. References: The explanation is based on the concepts covered in the SPCOR course, specifically the sections on MPLS LDP configuration and optimization. For more detailed information, refer to the official Cisco SPCOR course materials and documentation available at Cisco’s official training page.

In Cisco hardware, when a high bandwidth multicast stream is sent over a Multicast VPN (MVPN), a data Multicast Distribution Tree (MDT) is specifically created for that stream. This data MDT is used in addition to the default MDT, which is used for lower-bandwidth or control traffic. The purpose of the data MDT is to optimize the transmission of high-bandwidth streams through the core of the network, ensuring that the multicast traffic is only sent to those PE routers that have local receivers for the multicast group in question. This mechanism helps in efficiently using network resources and provides a scalable solution for transmitting high-bandwidth multicast streams.

References: The explanation is based on the concepts outlined in the Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course, which covers the configuration, verification, troubleshooting, and optimization of Service Provider IP network infrastructures, including advanced topics like MVPN and MDTs

Router R1 establishes TCP connections that are authenticated with an MD5 password. In the context of BGP (Border Gateway Protocol), TCP is used for establishing connections, and MD5 passwords can be used for authentication to enhance security.

• The Forward Error Correction (FEC) field within the OTN (Optical Transport Network) signal structure is responsible for error correction. When data arrives at the receiver, the FEC field helps correct any errors that may have occurred during transmission. It enhances the reliability of optical communication by detecting and rectifying errors.
• References: Implementing and Operating Cisco Service Provider Network Core Technologies course materials.

RSVP-TE Fast Reroute (FRR) is a mechanism that provides protection switching for MPLS TE LSPs. The Point of Local Repair (PLR) will prefer to use a next-hop (NHOP) backup tunnel over a next-next-hop (NNHOP) backup tunnel when both are available. This preference is due to the fact that NHOP backup tunnels can provide faster rerouting around the failure point, minimizing traffic disruption and packet loss.

References: The information is based on the RSVP-TE FRR deployment considerations from the Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course materials.

When a prefix list is applied to a BGP neighbor, it filters routes based on the specified conditions. In this scenario, the prefix list is designed to permit prefixes that are equal to or longer than /17 but shorter than or equal to /19. Therefore:

• A: 192.168.0.0/19 is denied because it falls outside the specified range.
• D: 192.168.0.0/16 is denied as it is shorter than the minimum length of /17.
• E: 192.168.0.0/16 is permitted because it is the exact prefix specified in the prefix list, and the ge and le modifiers apply to more specific routes derived from this prefix. References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - Cisco official courseware.

The configuration for R1 indicates a BGP neighbor relationship with a device in AS 65012. However, R2 is actually in AS 65000, leading to a mismatch in AS numbers. This discrepancy will prevent the establishment of a BGP neighbor relationship between R1 and R2.

 To monitor memory consumption and buffer statistics securely on P and PE devices in an MPLS core, especially considering the high CPU usage, the engineering team should implement SNMP version 3 for its security features. Therefore, option A is correct as it specifies SNMP version 3 with authentication. Option B is also correct as it enables traps for memory buffer peak, which is essential for monitoring memory thresholds and ensuring quick response to potential issues.

The service provider must implement a QoS configuration that includes traffic policing to enforce the contracted bandwidth limits. Option B is the correct choice because it specifies a committed information rate (CIR) of 512 kbps, which matches the customer’s contracted rate. The configuration also includes a burst size that accommodates the Tc value of 125 ms, allowing for brief periods of higher traffic without dropping packets. This setup ensures that under peak conditions, any traffic exceeding the contracted rate is either marked or dropped, thus preventing the customer from exceeding the agreed-upon bandwidth. References := For more detailed information on QoS configurations for Frame Relay networks, refer to the Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course materials, which cover the principles of traffic policing and shaping in service provider environments

IOS XE:

It uses linux-based kernel

It has a separate control plane

IOS:

It is monolithic

It shares memory space

OSPFv3 is used for routing IPv6 prefixes and requires that each interface intended to participate in OSPFv3 has the protocol enabled. This involves specifying the OSPF process ID and the area ID that the interface belongs to. The process ID links the interface to a specific OSPFv3 process running on the router, and the area ID determines the area within the OSPF topology that the interface is part of. Without this configuration, the interfaces will not actively participate in OSPFv3 route advertisement or neighbor relationships12.

References :=

• Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) course materials3.
• Cisco OSPFv3 configuration guides and examples

• In Option A, the configuration correctly classifies and marks management protocols with DSCP AF23, which belongs to AF class 2 with low drop probability.
• Monitoring protocols are marked with DSCP AF13, aligning with AF class 1 and low drop probability.
• All other traffic is marked with a DSCP value of 0, as required.

References:

• Cisco’s official guide on Implementing and Operating Cisco Service Provider Network Core Technologies

 mVPN (Multicast Virtual Private Network) is designed to support the efficient transport of multicast streams across a Layer 3 VPN. It enables service providers to use their existing MPLS networks to transport multicast traffic, allowing for scalable and manageable multicast delivery without requiring a separate network infrastructure. References: Implementing and Operating Cisco Service Provider Network Core Technologies

The neighbor relationship is down because R2 is operating as a Level 1 router and the two routers are in different areas. In the IS-IS (Intermediate System to Intermediate System) protocol, Level 1 routers exchange routing information with other Level 1 routers in the same area, while Level 2 routers exchange information between areas. Since R1 is configured as a level-2 router and R2 as a level-1 router, they cannot form a neighbor relationship if they are not in the same area. References: Implementing and Operating Cisco Service Provider Network Core Technologies source documents or study guide

YANG (Yet Another Next Generation) is a data modeling language used to model configuration and state data of a network. It is used to define the data structure of configuration files and is widely used for network configuration and management. YANG uses containers to categorize related nodes, allowing for a hierarchical organization of the data. Types can be associated with each leaf, but they are not required. Spines are not used in YANG, and it is not a distributed model of nodes.

 The MPLS LSP ping is the utility that must be used to locate MPLS faults. It is specifically designed to troubleshoot Multiprotocol Label Switching (MPLS) by sending a ping through the MPLS network to verify the path and identify any issues.

References: Cisco provides a guide on MPLS Troubleshooting

The ISIS topology exhibit indicates that all four routers are configured as Level 1-2 routers, which means they can operate in both Level 1 and Level 2 IS-IS areas. This is evident from the net addresses that show a mix of area addresses, allowing for intra-area (Level 1) and inter-area (Level 2) routing. Additionally, R1 and R2 are Level 2 neighbors because they have different area addresses, allowing them to form Level 2 adjacencies and route between different areas.

References: = Implementing and Operating Cisco Service Provider Network Core Technologies course materials. 

YANG (Yet Another Next Generation) is a data modeling language used primarily for the configuration and state data of network elements. It is closely associated with the NETCONF (Network Configuration Protocol) for which it models configuration data. YANG provides schemas that define how data is structured and transported by NETCONF operations. It also shapes the state data of network elements, allowing for a standardized format for representing the operational state of devices. References: YANG is defined in RFCs such as RFC 6020 and RFC 7950, which outline its role in NETCONF operations and its capabilities in modeling both configuration and state data.

In IS-IS, to advertise only the network prefixes associated with passive interfaces, the command advertise passive-only under the address family configuration mode is used. This ensures that only the prefixes of passive interfaces are advertised to other IS-IS routers in the network. The passive interface command is used to prevent IS-IS from forming adjacencies over that interface, while still allowing the network prefix of the interface to be included in the IS-IS link-state database.

References: For a comprehensive understanding, refer to the “Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR)” source book and study guide

 When interface Gi0/0/0/2 is shut down for maintenance, the other interfaces’ states are affected based on their current configurations and roles. In this case, Gi0/0/0/0 becomes active because it is next in line to take over the traffic load, ensuring that network service remains uninterrupted. Gi0/0/0/1 remains standby as it was before the shutdown of Gi0/0/0/2.

References: The explanation can be inferred from understanding Cisco’s technology and protocols related to interface states and bundle ether configurations,

1: graceful restart 2: IGP synchronization 3: session protection 4: targeted-hello accept

 The correct route policy to satisfy the requirements is Option C. This option likely contains the necessary commands to:

• Accept only customer-assigned prefixes, which can be specified using an access list or prefix list.
• Preserve customer advertised BGP communities, which is typically done with the set community command along with the additive keyword to ensure existing communities are not overwritten.
• Set the local-preference to 110 for all prefixes, which is achieved with the set local-preference 110 command.
• Attach the ORIGINATION-PE and LOCAL-CITY communities to all accepted prefixes, which would also use the set community command with both community values specified and the additive keyword.

References: The Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) training materials provide detailed information on BGP and route policies, including how to configure route maps and policy-based routing to control path selection and maintain BGP community information.

R1

Router bgp 65515

No bgp default ipv4-unicast

Neig 2.2.2.2 remote-as 65516

Nei 2.2.2.2 update-soc loopback0

Nei 2.2.2.2 ebgp-multihop 2

Neig 2.2.2.2 pass C1sc0!

Nei 2000:cc13:cc13:2::1 remote-as 65516

Nei 2000:cc13:cc13:2::1 update-so loopback0

Nei 2000:cc13:cc13:2::1 pass C1sc0!

Nei 2000:cc13:cc13:2::1 ebgp-multihop 2

Address-family ipv4

Neig 2.2.2.2 activate

Address-family ipv6

Nei 2000:cc13:cc13:2::1 activate

Ip route 2.2.2.2 255.255.255.255 192.168.1.2

Ipv6 route 2000:cc13:cc13:2::1/128 2000:cc13:cc13:cc13::2

R2

Router bgp 65516

No bgp default ipv4-unicast

Neig 1.1.1.1 remote-as 65515

Nei 1.1.1.1 update-soc loopback0

Nei 1.1.1.1 pass C1sc0!

Nei 1.1.1.1 ebgp-multihop 2

Nei 2000:cc13:cc13:1::1 remote-as 65515

Nei 2000:cc13:cc13:1::1 update-so loopback0

Nei 2000:cc13:cc13:1::1 pass C1sc0!

Nei 2000:cc13:cc13:1::1 ebgp-multihop 2

Address-family ipv4

Neig 1.1.1.1 activate

Address-family ipv6

Nei 2000:cc13:cc13:1::1 activate

Ip route 1.1.1.1 255.255.255.255 192.168.1.1

Ipv6 route 2000:cc13:cc13:1::1/128 2000:cc13:cc13:cc13::1

MPLS traffic-engineering tunnels can be configured with dynamic paths or explicitly defined paths across the core network. Tunnel links inherit IGP (Interior Gateway Protocol) metrics by default unless overridden by configurations that specify explicit paths or other criteria for path selection. Dynamic path tunnels use IGP metrics and other parameters like bandwidth availability for automatic path calculation. References: Implementing and Operating Cisco Service Provider Network Core Technologies source documents or study guide

The correct configuration for the BGP route policy named SUBNET, as per the second set of text in the image details, is to drop traffic if the destination is in BGP. Otherwise, the MED value should be set to 400 and community (4:400) should be added. This matches Option B, which specifies these exact actions. References := The information is based on the image details provided and aligns with common BGP route policy configurations typically found in Cisco’s service provider network core technologies documentation.

 The REST API command shown in the exhibit is a POST request to a specific URL, indicating that it is used to submit data to be processed to a specified resource. In this case, the resource is an XML file named “Descriptions.xml”. POST requests are used when submitting data to be processed by the resource identified by the URI. The nature of the process conducted on the submitted data depends on that particular URI. References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - REST API section.

MPLS LSP ping is a utility for locating faults within an MPLS network, specifically for Label Switched Paths (LSPs). It helps in verifying the LSPs in the MPLS network. The utility sends echo requests to the destination, and if the path is complete, echo replies are received. References := Cisco

 To ensure that traffic for the prefix 192.168.1.1/32 travels via the alternate path R6-R5, a route-map with a higher local preference should be applied inbound on R3 for neighbor R6. This will make the path through R6-R5 more preferable, thus meeting the requirement. References := Implementing and Operating Cisco Service Provider Network Core Technologies

The mpls ldp graceful-restart command is applied in the global configuration mode in IOS XE Software. This command enables MPLS LDP Graceful Restart, which assists a neighboring router with MPLS LDP Stateful Switchover/Nonstop Forwarding (SSO/NSF) Support and Graceful Restart to recover gracefully from an interruption in service without losing its MPLS forwarding state1.

References: MPLS Configuration Guide, Cisco IOS XE 17.x1.

To inject a default route into the MP-BGP address family for a dedicated VRF, you would typically need to:

• Configure a static default route in the VRF using the ip route vrf 0.0.0.0 0.0.0.0  command.
• Redistribute the static route into BGP using the redistribute static command under the BGP VRF configuration.

To view login history for users who activated a session, the network administrator can use the show netconf-yang sessions command. This command provides information about active NETCONF/YANG sessions, including the login times for each user.

References:

• Cisco Community - Any command to see login history using CLI
• WinTips.org - How to View User Login History in Windows 10/11
• nixCraft - Linux Display Date And Time Of Login

 The configuration in the exhibit shows that R1 is configured with “mpls ldp graceful-restart”, which enables LDP Graceful Restart on the router. This means that R1 can support a graceful restart operation on the peer, even if graceful restart is disabled on the peer. This feature allows LDP to recover from failures without affecting the forwarding plane, ensuring network stability and minimal packet loss during failovers.

References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - Cisco SPCOR Training & Certification

The absence of routes learned by PE4 from PE5 in other PE routers’ routing tables is likely due to missing route target configurations. Route targets are crucial for importing and exporting VPN routes between VRFs in MPLS Layer 3 VPNs.

• Option D is correct because advertising the route targets for PE5 to the other PEs will allow them to import routes from PE5 into their respective VRFs, facilitating communication across the Layer 3 VPN.

References :=

• Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) source book and study guide.