MPLS and Segment Routing

A service provider is designing a new MPLS core network using Segment Routing with MPLS data plane. They require traffic engineering capabilities to optimize bandwidth utilization. Which technology should be used to compute optimal paths based on IGP link attributes and bandwidth constraints?

A service provider is deploying a new MPLS core with Segment Routing and requires fast convergence upon link failure. They plan to use TI-LFA (Topology Independent Loop-Free Alternate). What is a prerequisite for TI-LFA to provide protection against any single link failure?

Which TWO statements about MPLS label switching are correct? (Choose two.)

Which THREE of the following are benefits of using Segment Routing over LDP in an MPLS network? (Choose three.)

An engineer is designing an MPLS network and needs to ensure that VPN traffic between two PE routers is label-switched. The PE routers are connected via a P router and have a full mesh of iBGP sessions. Which label distribution method is required for the VPN labels?

Which TWO are benefits of using Segment Routing (SR) over traditional LDP-based MPLS?

A service provider has a network with PE1, P1, P2, and PE2 connected in a chain: PE1-P1-P2-PE2. The IGP is IS-IS with wide metrics, and MPLS LDP is enabled on all interfaces. The goal is to provide L3VPN services between PE1 and PE2. The engineer has configured MP-iBGP between PE1 and PE2, and the VPNv4 routes are exchanged. However, when a CE router behind PE1 tries to reach the CE behind PE2, the traffic fails. The engineer checks the MPLS forwarding table on PE1 and sees that the label for the BGP next-hop (PE2's loopback) is 'Untagged'. The BGP next-hop is reachable via ICMP. What is the most likely cause of this issue?

A service provider is deploying MPLS-TE with RSVP-TE in their core network. They notice that some LSPs are not being established due to resource contention. Which action would best address this issue without redesigning the entire traffic engineering deployment?

A service provider is designing a greenfield MPLS core and wants to minimize control-plane complexity while still supporting traffic engineering. They plan to use Segment Routing with MPLS. Which statement about Segment Routing in this context is accurate?

Drag and drop the steps for the BGP route selection process (best path selection) in order.

A large enterprise uses MPLS L3VPN to connect multiple sites. They want to implement inter-AS option B (ASBR-to-ASBR MP-eBGP) for scalability. Which statement about this model is correct?

An MPLS core network uses LDP to distribute labels. An engineer wants to verify that the LDP session between two routers is up and exchanging labels. Which command should be used?

Which TWO statements correctly describe Segment Routing characteristics? (Select two.)

Which TWO types of SIDs are defined in Segment Routing? (Select two.)

Which protocol is typically used to distribute MPLS labels between directly connected LSRs?

Which BGP address family must be used to exchange VPNv4 routes between PE routers in an MPLS L3VPN?

An engineer is troubleshooting MPLS traffic engineering tunnels and needs to verify path calculation and RSVP errors. Which command should be used?

In MPLS forwarding, what label operation does a transit LSR perform on the top label of a labeled packet?

Which BGP extended community is used to signal the OSPF domain ID between PE routers in an MPLS L3VPN when OSPF is the PE-CE protocol?

Which tool can verify connectivity along an MPLS Label Switched Path (LSP) and detect label loops?

An engineer notices that MPLS VPN traffic is taking a suboptimal path because the MPLS label binding for the BGP next-hop loopback is missing. What is the most likely cause?

In an MPLS L3VPN network with route reflectors, what is the default behavior regarding the BGP next-hop attribute for reflected VPNv4 routes?

A service provider is deploying MPLS in their core network and wants to ensure that all routers in the MPLS domain can dynamically exchange label bindings. Which protocol should be enabled on all routers to meet this requirement?

A network operator is configuring RSVP-TE tunnels for traffic engineering in an MPLS core. They want to enforce that the tunnel path strictly follows a predefined set of hops. Which explicit path option should be used?

In an MPLS L3VPN network, a customer has overlapping IP addresses between two VPNs. The provider edge routers are configured with VRF instances. Which method ensures that traffic from one VPN does not leak into the other when using MPLS labels?

A service provider is implementing Segment Routing over IPv6 (SRv6) in their core. They want to provide path isolation for different services using SRv6 SIDs. Which SID structure is used to encode both the locator and the function?

Which two statements about MPLS label operations are true? (Choose two.)

Which three are required components for deploying Segment Routing in an MPLS network? (Choose three.)

Refer to the exhibit. The output shows an MPLS forwarding entry with FRR protection. What is the purpose of the backup path shown?

A service provider is designing a new MPLS core network and wants to simplify traffic engineering without deploying a centralized controller. Which technology should be used to enable source-routed paths with explicit path control?

A service provider is migrating from LDP-based MPLS to Segment Routing (SR-MPLS) with IS-IS. After enabling SR on all routers, the adjacency segment IDs (ADJ-SIDs) are not being advertised. Which configuration is missing?

A network architect is designing an MPLS network that must provide fast convergence in case of a link failure. The network uses Segment Routing. Which mechanism provides sub-50ms protection by using a precomputed backup path?

Which TWO are characteristics of Segment Routing (SR-MPLS)? (Choose two.)

Which THREE steps are required when configuring MPLS L3VPN on a PE router? (Choose three.)

Which TWO commands are most effective to verify that an SR-TE policy is active and forwarding traffic? (Choose two.)

An SP network engineer is designing a new segment routing traffic engineering deployment within a single IGP area. The network consists of 50 core routers running IS-IS and MPLS. The engineer needs to steer traffic from Router A to Router D over a path that avoids high latency links. Which technology should be used to define and instantiate the explicit path?

In an MPLS L3VPN network, a route reflector (RR) is used to distribute VPNv4 routes between PE routers. After a new PE router (PE4) is added, some VPN routes are not being received by other PEs. Which TWO actions should be investigated to resolve the issue? (Choose two.)

Refer to the exhibit. The router has three LDP neighbors established. A network administrator notices that MPLS labels for the prefix 10.4.4.0/24 are not being advertised from this router to its neighbors, although the prefix is present in the routing table. Which is the most likely cause?

An engineer is configuring MPLS LDP on a Cisco router. The router uses downstream unsolicited mode with liberal label retention. Which behavior describes the label distribution and retention on this router?

An engineer is deploying MPLS-TE with FRR using the 1:1 detour method. Which statement about link protection in this scenario is true?

In Segment Routing (SR-MPLS), which IGP TLV is used by IS-IS to advertise the Node SID for a prefix?

Which RSVP message is used to tear down an MPLS-TE LSP by being sent from the ingress toward the egress?

What is the primary purpose of the SRGB (Segment Routing Global Block) when configuring SR-MPLS on a network?

In EVPN-VPWS, which component is used to identify a multi-homed Ethernet segment and enable load balancing and fast convergence?

In MPLS-TE, what is the purpose of the Explicit Route Object (ERO) in the RSVP PATH message?

An engineer configures an SRv6 SID with the behavior End.DT6. What is the primary function of this SID?

An engineer is configuring EVPN IRB (Integrated Routing and Bridging) to provide IP connectivity between tenants across a service provider network. Which THREE components are essential for EVPN IRB operation? (Choose three.)

In MPLS, which label operation is performed by a Penultimate Hop Popping (PHP) router?

Which label distribution mode does LDP use by default in Cisco IOS?

In Segment Routing for MPLS (SR-MPLS), which TLV is used in IS-IS to advertise the Node SID?

Which label is used for an Adjacency SID in SR-MPLS?

What is the purpose of Constrained Shortest Path First (CSPF) in MPLS-TE?

In SRv6, what is the function of the 'End.DT4' behavior?

In MPLS-TE Fast Reroute (FRR), what is a 'detour'?

Which EVPN component ensures that only one of the multi-homed PEs forwards traffic to the CE for a given Ethernet segment?

In SR-MPLS, what is the purpose of the SRGB (Segment Routing Global Block)?

Which two statements about LDP liberal label retention are true? (Choose two.)

Which three are characteristics of SR-TE policies? (Choose three.)

Which two are benefits of using EVPN-VPWS over traditional VPWS? (Choose two.)

In MPLS, what is the term for the operation where the top label is removed and replaced with a new label?

In RSVP-TE, which message is sent by the headend router along the explicit route to reserve resources and establish an LSP?

An engineer is configuring MPLS-TE FRR for link protection. Which of the following options describes a 1:1 protection scheme where a dedicated detour LSP is created for each protected LSP?

Which SRv6 endpoint behavior is used for L3VPN decapsulation and IP forwarding to the destination in a VRF?

In SR-TE, a headend router is configured with an SR Policy that includes an explicit candidate path with segment list [16001, 16003, 16005]. What does this segment list represent?

Which of the following best describes the function of CSPF in MPLS-TE?

In MPLS, which forwarding table is used to determine the outgoing label and interface for a labeled packet?

Which TWO statements about MPLS label operations are correct? (Choose two.)

In MPLS, which operation occurs when a router receives a labeled packet and replaces the top label with a new label before forwarding?

Which LDP mode uses downstream unsolicited label distribution and liberal label retention?

An engineer configures an MPLS-TE tunnel with a bandwidth of 100 Mbps and an explicit path that avoids a specific link. Which RSVP message carries the Explicit Route Object (ERO) to signal the path?

Which SR-MPLS SID is advertised by an IS-IS router to identify a specific link and is distributed only to adjacent neighbors?

In SRv6, which SID behavior is used to achieve L3VPN IPv6 VPN forwarding, where the SID points to a VPN instance and performs decapsulation and IPv6 lookup?

Which component of an MPLS-TE FRR (Fast Reroute) configuration provides protection for the next-hop node by bypassing it?

An engineer wants to configure SR-TE without using RSVP. Which mechanism does SR-TE use to specify the explicit path?

In EVPN-VPWS, which identifier is used to uniquely identify an Ethernet Segment for multi-homing?

In CSPF (Constrained Shortest Path First) for MPLS-TE, which of the following is NOT a typical constraint considered during path computation?

Which MPLS label operation is performed by the penultimate hop router in PHP (Penultimate Hop Popping)?

An SRv6 SID is composed of three parts: Locator, Function, and Arguments. Which part identifies the SRv6-capable node in the network?

Which TWO statements correctly describe RSVP-TE reservation styles? (Choose two.)

Which TWO are characteristics of SR-MPLS when compared to LDP-based MPLS? (Choose two.)

An engineer is configuring MPLS LDP on a Cisco router. The router is using downstream unsolicited mode and liberal label retention. Which statement correctly describes the label advertisement behavior?

In an MPLS-TE tunnel configuration, which RSVP message carries the Explicit Route Object (ERO) that specifies the explicit path the tunnel must follow?

A network operator is implementing segment routing (SR-MPLS) using OSPF as the IGP. Which OSPF TLV is used to advertise the Node SID (Prefix SID) for a router's loopback address?

An engineer is configuring RSVP-TE fast reroute for link protection. Which protection method uses a pre-configured bypass tunnel that protects multiple LSPs on the same link?

In SRv6, which behavior is used for L3VPN decapsulation (removing the outer IPv6 header and SRH, and forwarding the inner IPv4 packet based on the VPN routing table)?

What is the purpose of the SRGB (Segment Routing Global Block) in SR-MPLS?

In an EVPN-VPWS (Virtual Private Wire Service) deployment, which identifier is used to uniquely identify an Ethernet Segment for multi-homing?

Which component of SRv6 SID format is used to identify the specific function (e.g., End, End.X) on the node?

Which label distribution protocol is replaced by segment routing in SR-MPLS deployments?

When configuring an MPLS-TE tunnel with affinity/constraint-based routing, what is the effect of assigning a link attribute of 'red' and setting the tunnel's affinity to include 'red' with the 'include-all' keyword?

An engineer is configuring MPLS on a Cisco router. Which label operation is performed on the ingress LSR when a packet enters the MPLS domain?

An MPLS TE tunnel is configured with an explicit path. Which RSVP message is used by the headend to signal the path and carry the Explicit Route Object (ERO) listing the hops?

In RSVP-TE, which filter spec style allows multiple senders to share the same reserved resources on a link, as long as their flows do not exceed the reservation?

In SRv6, which endpoint behavior is used for decapsulation and forwarding to a Layer 3 VPN IPv4 destination, removing the outer IPv6 header?

Which component in EVPN is used to uniquely identify an Ethernet segment across multiple PE devices in a multi-homing scenario?

Which THREE are valid SRv6 endpoint behaviors for VPN services? (Choose three.)

Which THREE are mechanisms used in EVPN to support multi-homing and load balancing? (Choose three.)

In an MPLS network using LDP, which statement correctly describes the label distribution behavior for a given FEC?

In SR-MPLS, which mechanism replaces LDP for label distribution?

An engineer configures an RSVP-TE tunnel with a bandwidth of 100 Mbps and an explicit path that excludes a specific interface. The tunnel fails to come up. Which term describes the path computation method used by RSVP-TE to find a feasible path given these constraints?

In SR-MPLS, when a router receives a packet with an MPLS label corresponding to an Adjacency SID, what operation does it perform?

An engineer is implementing MPLS-TE Fast Reroute for link protection. Which protection method provides a backup tunnel that bypasses a specific link, protecting all LSPs traversing that link?

In Segment Routing over IPv6 (SRv6), what is the function of the 'Locator' part of an SRv6 SID?

An operator is deploying EVPN-VPWS over an MPLS network. Which component uniquely identifies a multihomed Ethernet segment in EVPN?

In SR-MPLS TE, a headend router is configured with an SR Policy that includes an explicit candidate path with segment list [16001, 16003]. What do these numbers represent?

Which LDP label retention mode stores all received label bindings even if they are not currently used for forwarding?

In SRv6, which endpoint behavior is used for decapsulating the outer IPv6 header and performing an IPv4 lookup (e.g., for L3VPN)?

An engineer is troubleshooting an MPLS network where some routers are not exchanging labels via LDP. Which two steps are most appropriate for diagnosing the issue? (Choose two.)

In SR-MPLS traffic engineering, which three components are essential for configuring an SR Policy on a headend router? (Choose three.)

In EVPN multi-homing, which two mechanisms are used to avoid duplicate packets and ensure efficient forwarding? (Choose two.)

Which three statements accurately describe the benefits of Segment Routing over RSVP-TE for traffic engineering? (Choose three.)

A network engineer is designing a Segment Routing over IPv6 (SRv6) deployment. Which TWO statements are true about the SRv6 SID format and behaviors? (Choose two.)

An SP network uses RSVP-TE for MPLS traffic engineering with FRR link protection. Which THREE statements are correct about RSVP-TE operation and FRR? (Choose three.)

An engineer is configuring MPLS LDP on a Cisco router. Which TWO statements about LDP operation are correct? (Choose two.)

A service provider runs an MPLS L3VPN over an SR-MPLS core. The PE router connects to a customer edge (CE) device that uses a different routing protocol. The PE must redistribute the CE routes into the VPN routing and forwarding (VRF) instance and advertise them to remote PEs. Which of the following is the correct first step to ensure that the CE routes are advertised as VPNv4 prefixes to remote PEs?

A network engineer is deploying MPLS L3VPN on Cisco IOS XR routers. The PE router must maintain separate VRF routing tables and advertise VPNv4 prefixes to remote PEs. Which protocol is required to carry VPNv4 routes between PE routers?

An engineer is troubleshooting an MPLS L3VPN where the customer edge routers can exchange routes with the provider edge routers, but the provider edge routers are not exchanging VPNv4 routes with each other. The engineer verifies that the iBGP session between the provider edge routers is established using the loopback interfaces and that the underlying IGP is converged. Which action must be taken to allow the provider edge routers to exchange VPNv4 routes?

An engineer is configuring an SR-MPLS TE policy on a Cisco IOS XR headend router. The policy uses a dynamic path computed by a PCE, and the headend must signal the policy using the PCEP protocol. Which statement correctly describes the role of the PCE in this scenario?

A service provider runs an MPLS L3VPN with OSPF as the PE-CE routing protocol. A customer reports that routes from one site are not being installed into the VRF of another site's PE router, even though the MP-BGP session between the PEs is established and the VPNv4 prefixes are present. Which action should be taken to resolve this issue?

A network operator is configuring an MPLS L3VPN on a Cisco IOS XR PE router. The operator needs to define a VRF that will be used for a customer and must ensure that the customer's routes are imported into the correct VRF on remote PEs. Which of the following must be configured to identify the VRF and control route import?

A network administrator is configuring MPLS LDP on a Cisco IOS XE router. The router must establish LDP sessions with directly connected neighbors. Which command enables LDP on an interface?

A network engineer is configuring an MPLS L3VPN on a Cisco IOS XR PE router. The customer edge router is connected to the PE via a VRF interface. The engineer notices that the PE is not advertising the VPNv4 prefix to its remote PE peer. Which configuration step is most likely missing?

A service provider's MPLS core uses LDP for label distribution. The network operations team wants to migrate to Segment Routing (SR-MPLS) without disrupting existing LDP-based LSPs during the transition. On a Cisco IOS XR router, which configuration step allows both LDP and SR-MPLS to coexist and forward traffic simultaneously?

A network administrator is configuring MPLS LDP on a Cisco IOS XE router. The router must establish LDP sessions with its directly connected neighbors. Which transport protocol and port does LDP use for session establishment and label exchange?

A service provider is using MPLS L3VPN with BGP as the PE-CE routing protocol. A customer reports that routes from one site are not being installed in the VRF of another site. The engineer verifies that the PE routers have established BGP sessions with the CEs and that the VPNv4 routes are being exchanged between PEs. Which configuration element must be verified to ensure that the customer routes are imported into the correct VRF?

An engineer is troubleshooting an MPLS L3VPN where customer routes are not being installed in the VRF on a PE router. The PE receives VPNv4 routes from a remote PE, but the routes are not present in the VRF routing table. Which configuration element is most likely misconfigured?

A network engineer is deploying Segment Routing over an MPLS network using OSPF as the IGP. The engineer wants to enable SR-MPLS and ensure that Prefix-SIDs are advertised. Which TWO steps are required to accomplish this? (Choose two.)

A service provider is deploying EVPN with Integrated Routing and Bridging (IRB) to provide inter-subnet routing for a customer. The customer has two subnets, and the provider wants to enable routing between them on the PE routers. Which of the following is required to support IRB in an EVPN environment?

A service provider runs IS-IS as its IGP and is deploying Segment Routing MPLS. The network architect wants to ensure that MPLS forwarding entries for Prefix-SIDs are installed in the LFIB even before any SR policy traffic is sent. On a Cisco IOS XR router, which configuration step is required to enable SR-MPLS forwarding for the IS-IS domain?

A network engineer is deploying an SR-MPLS Traffic Engineering (SR-TE) policy on a Cisco IOS XR headend router. The policy uses a segment list with two SIDs: 16002 and 16005. The engineer wants to verify that the policy is correctly installed and that traffic is being forwarded along the intended path. Which two commands would provide the necessary verification? (Choose two.)

An engineer is configuring an MPLS L3VPN on a Cisco IOS XR PE router. The customer edge (CE) router is connected via a VRF named CUST1. The engineer must ensure that the PE router can forward traffic between the CE and the MPLS core. Which of the following is required to complete the configuration?

An engineer is configuring MPLS L3VPN on a Cisco IOS XR PE router. The customer edge router is connected via a VRF interface. Which of the following is required to enable the PE router to advertise VPN routes to other PE routers?

A service provider is using MPLS L3VPN with BGP as the PE-CE routing protocol. A customer reports that routes from one site are not being advertised to another site. The engineer checks the PE routers and finds that the VPNv4 prefixes are present in the BGP table but not installed in the VRF routing table. What is the most likely cause?

A service provider is deploying MPLS L3VPN services and wants to use Segment Routing instead of LDP for label distribution. The network uses OSPF as the IGP. Which configuration step is required on each router to enable Segment Routing for MPLS with OSPF?

A network engineer is deploying Segment Routing over an MPLS core using IS-IS as the IGP. The engineer wants to enable SR-MPLS on all routers. Which command is required under the IS-IS address family configuration on a Cisco IOS XR router to enable Segment Routing?

A service provider is migrating from LDP to Segment Routing in an IS-IS network. During the migration, the engineer notices that some routers are not advertising Prefix-SIDs for their loopback interfaces. Which of the following is the most likely cause?

A network administrator is verifying the MPLS forwarding table on a Cisco IOS XR router. The administrator wants to display the incoming label, outgoing label, and next-hop for all MPLS entries. Which command should be used?

An engineer is troubleshooting an SR-MPLS TE tunnel that is not coming up. The headend router is configured with an explicit candidate path that uses a segment list containing SIDs 16010, 16020, and 16030. The show segment-routing traffic-eng policy command indicates that the policy is down. Which of the following is the most likely cause?

An engineer is troubleshooting an SR-MPLS TE tunnel in a Cisco IOS XR network. The headend router has an SR Policy with an explicit candidate path that contains a segment list with the SIDs of the desired path. However, the tunnel is not forwarding traffic. The engineer checks the segment list and sees that the first SID is a node SID of an intermediate router, and the last SID is the node SID of the destination. What is the most likely cause of the issue?

A network engineer is configuring MPLS LDP on a Cisco IOS XR router. The engineer wants to restrict label advertisement to only those prefixes that are in the routing table and have a specific tag. Which LDP feature should be used?