25 of 100 questions · Page 2/2 · Spcor Architecture topic · Answers revealed
A service provider wants to automate service provisioning using NSO. Which protocol is typically used by NSO to configure network devices?
Correct. NETCONF is used for configuration management with YANG models.
Why this answer
NSO uses NETCONF as the primary protocol for device configuration, leveraging YANG models for service modeling.
Which TWO are benefits of using EVPN over traditional VPLS for L2VPN services? (Choose two.)
EVPN uses BGP to advertise MAC routes.
Why this answer
EVPN offers better control plane (BGP) and supports multi-homing with all-active load balancing.
Which THREE are MEF-defined Ethernet service types? (Choose three.)
Multipoint-to-multipoint Ethernet service.
Why this answer
MEF defines E-Line, E-LAN, and E-Tree. E-Access is also defined but is not part of the three main types. E-WAN is not a standard MEF service.
What is the function of the admin plane in IOS XR architecture?
Correct. The admin plane manages SDR creation and system-level configuration.
Why this answer
The admin plane is a separate management context for administrative tasks such as configuring SDRs, managing hardware, and system-level settings. It provides isolation from the default SDR.
A service provider is designing a network to support mobile backhaul for eMBB, uRLLC, and mMTC services. Which technology allows the physical network to be divided into virtual networks with dedicated resources for each service type?
Network slicing is the correct technology.
Why this answer
Network slicing enables multiple virtual networks on a shared physical infrastructure, each with tailored performance characteristics.
Which THREE are benefits of using EVPN over traditional VPLS? (Choose three.)
EVPN advertises MACs via BGP, allowing mobility.
Why this answer
EVPN offers BGP-based control plane, multi-homing support, and MAC mobility. VPLS traditionally uses LDP and does not natively support multi-homing or MAC mobility as effectively.
A service provider is migrating from LDP to Segment Routing (SR) in the core. They need to support MPLS forwarding without maintaining LDP sessions. Which SR data plane is appropriate?
Correct. SR-MPLS uses IGP to advertise labels, no LDP needed.
Why this answer
Segment Routing with MPLS data plane (SR-MPLS) uses IGP to distribute labels, eliminating the need for LDP. SR-MPLS is the direct replacement for LDP in MPLS networks.
In IOS XR, what is the commit/rollback configuration model?
This is the correct description.
Why this answer
The commit/rollback model applies changes atomically and allows reverting to previous configurations if needed.
Which THREE are characteristics of EVPN? (Choose three.)
Correct. EVPN supports all-active and single-active.
Why this answer
EVPN uses BGP control plane, supports multi-homing with ESI, and can provide both L2 and L3 services. It does not use LDP for signaling; it uses BGP. VPLS is older.
A metro Ethernet provider needs to scale customer VLANs beyond the 4,096 limit by encapsulating customer VLAN tags with an outer service provider tag. Which IEEE standard is used?
802.1ad allows double tagging with an outer service provider tag.
Why this answer
Q-in-Q (802.1ad) adds an outer VLAN tag to extend VLAN space. 802.1ah is for MAC-in-MAC, 802.1Q is the basic standard, and 802.1ak is not related.
A service provider wants to deploy network slicing for 5G services. Which THREE of the following are typical requirements for network slicing?
Automation is key for slice management.
Why this answer
Network slices require resource isolation (A), dedicated control plane functions (B), and end-to-end orchestration (E). Slices share physical resources (C is false) and do not necessarily require separate BGP AS (D).
VRF isolates routing per customer.
An SP uses Cisco NSO for automation. Which protocol does NSO typically use to push configuration changes to network devices?
NETCONF is the standard protocol for NSO.
Why this answer
NSO uses NETCONF as the primary protocol to push configuration changes, leveraging YANG data models.
Which MEF service type is used for multipoint-to-multipoint Ethernet connectivity, such as a corporate LAN extension across multiple sites?
E-LAN supports any-to-any communication.
Why this answer
E-LAN provides multipoint-to-multipoint connectivity, emulating a LAN across multiple locations.
In the context of network slicing for 5G, which type of slice is optimized for massive IoT with low data rates and high connection density?
mMTC supports massive IoT with high connection density.
Why this answer
Massive IoT corresponds to mMTC (massive Machine Type Communications) slice, designed for many devices with low data rates.
Correct. Each protocol runs as an independent process, ensuring fault isolation.
Why this answer
IOS XR uses a distributed OS where each protocol runs as a separate process (process separation). This prevents a crash in one protocol process from impacting others, enhancing stability.
Which access technology uses orthogonal frequency-division multiplexing (OFDM) and is commonly deployed for high-speed internet over copper telephone lines?
DSL uses copper telephone lines with OFDM.
Why this answer
VDSL2 and G.fast use OFDM, but DSL generally refers to xDSL technologies. However, the most common high-speed copper access is VDSL2, but the question is broad. The correct answer is DSL as a family.
A service provider wants to offer a service where a customer site can communicate with multiple other sites in a full mesh over MPLS. Which L2VPN technology is most appropriate?
VPLS provides multipoint connectivity.
Why this answer
VPLS (Virtual Private LAN Service) provides multipoint-to-multipoint Ethernet connectivity over MPLS, emulating a LAN.
An ISP wants to create separate virtual networks over a shared physical infrastructure to serve mobile broadband (eMBB), IoT (mMTC), and mission-critical services (uRLLC). Which technology enables this segmentation with per-slice resource guarantees?
Network slicing provisions isolated virtual networks with dedicated resources.
Why this answer
Network slicing divides the physical network into multiple virtual networks, each with dedicated resources for different service types. L3VPN, MPLS-TE, and VPLS do not provide per-slice resource guarantees natively.
Which access technology uses wavelength division multiplexing to provide symmetric gigabit speeds in fiber-optic networks?
XGS-PON uses WDM to deliver symmetric 10 Gbps.
Why this answer
XGS-PON uses wavelength division multiplexing to support symmetric 10 Gbps speeds, while GPON is asymmetric and DSL/cable are copper-based.
An SP is designing a metro Ethernet network using Q-in-Q. A customer uses VLAN ID 100 on their network, and the SP assigns service VLAN 200. Which frame format is used on the SP network?
Outer tag is service VLAN, inner is customer VLAN.
Why this answer
Q-in-Q adds an outer (service) VLAN tag (200) while preserving the inner (customer) VLAN tag (100).
Correct. Q-in-Q adds an outer tag to segregate customer traffic, allowing overlapping inner VLANs.
Which access technology is commonly used in service provider networks to deliver high-speed internet over existing telephone lines?
DSL uses telephone lines for broadband.
Why this answer
DSL (Digital Subscriber Line) uses existing telephone lines to provide high-speed internet access.
Which TWO of the following are benefits of using EVPN over traditional VPLS for L2VPN services?
EVPN uses MP-BGP to distribute MAC/VTEP information.
Why this answer
EVPN provides active-active multi-homing (B) and uses BGP for MAC learning (C), unlike VPLS which uses flooding and active/standby.
An SP uses Cisco ASR 9000 routers with IOS XR. Which statement correctly describes the commit/rollback configuration model in IOS XR?
This is the commit/rollback model.
Why this answer
IOS XR requires a 'commit' to apply changes; it supports rollback to previous committed configurations, allowing safe changes.
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