WAN for Enterprise Networks (20%)

ENSLD · 60 questions

• A regional bank branch has primary MPLS and backup Internet VPN with a floating static route. The business needs sub-second failure detection on the primary path and automatic failover only when the remote data-center prefix becomes unreachable. Which backup connectivity and failover trigger design meets both timing and reachability goals?
• A regional bank connects two data centers 80 km apart with sustained 40 Gbps replication, low latency, and full control of encryption keys. It leases dark fiber and needs deterministic performance without sharing bandwidth. Which DWDM-based leased optical connectivity use case best fits these requirements?
• A retailer is rolling out 200 SD-WAN branches with zero-touch onboarding, centralized templates and monitoring, secure device authentication, and distributed routing decisions. Which mapping of Cisco SD-WAN orchestration, management, control and data plane functions achieves this design?
• A retail chain with 40 stores needs any-to-any inventory traffic between stores and two data centers, plus a separate low-latency point-to-point link for payment processing between the primary data center and a bank cage. The carrier offers Metro Ethernet services with different forwarding and isolation options. Which Metro Ethernet design best fits these connectivity requirements?
• A retail chain is adding 40 small stores and wants the provider to carry routing between sites so the small IT team avoids managing a full mesh of tunnels or a large enterprise routing domain. Overlapping private addresses are not required, but simple adds and provider-managed path selection matter. Which WAN service should the designer recommend to meet the routing ownership and scaling need?
• A retailer dual-homes its headquarters to ISP-A and ISP-B with its own public /22, hosting e-commerce that must stay reachable if one ISP fails. Management wants outbound browsing to prefer ISP-A and inbound customers to enter via ISP-A when healthy. Which BGP multihoming path-control design should the designer propose for inbound and outbound preference?
• A city government needs to connect five downtown offices in one bridged domain for legacy applications, plus a separate isolated point-to-point link for data-center replication between two sites. Carrier offerings list E-Line and E-LAN options. Which Metro Ethernet design should the designer select to satisfy both connectivity patterns?
• A port operator runs primary fiber to a terminal and a 5G backup, needing sub-second detection of gateway loss to trigger floating static failover, but must ignore momentary jitter that causes flapping. Which backup connectivity and failover trigger design should the designer propose for fast yet stable detection?
• A utility operates remote substations where trenching fiber is cost-prohibitive and wired outages last days. Sites need backup connectivity for SCADA telemetry and occasional primary use for new locations. Which 4G/5G transport design as primary or backup best meets resilient requirements?
• A research university needs to transport 200 Gbps between two campuses 60 km apart for genomics replication, with strict loss and latency budgets, dedicated fiber control, and future growth to 400 Gbps. Carrier packet services cannot guarantee the optical performance and upgrade path required. Which optical connectivity approach best satisfies capacity and control needs?
• A logistics company is rolling out 60 SD-WAN branches with zero-touch provisioning, centralized configuration, loop-free route distribution, and encrypted site-to-site transport. The design must assign each task to the right plane. Which SD-WAN function mapping correctly places orchestration, management, control and data duties?
• An energy company must onboard 120 remote substations with limited local IT skills, strict certificate-based identity, and staged rollout by region. Templates should minimize per-site CLI. Which SD-WAN onboarding and provisioning approach best meets rapid secure deployment?
• A regional bank connects two data centers 70 km apart and needs 40 Gbps of low-latency replication, full control of encryption keys, and capacity to add wavelengths later without ordering new carrier circuits. The carrier offers dark fiber between sites and managed MPLS VPN. Which DWDM connectivity approach best meets the low-latency scaling requirement?
• A retailer with 80 stores is evaluating Cisco SD-WAN to replace costly MPLS, payment data must stay encrypted across broadband, stores need basic Internet protection, and IT wants integrated threat functions without adding appliances. Which SD-WAN built-in security capability best addresses this distributed retail need?
• A retail chain with 40 small stores needs backup connectivity for POS traffic when wired broadband fails, has limited IT staff, requires rapid deployment, and must maintain encrypted transport over the carrier network. Which WAN connectivity design using 4G/5G best meets the resiliency requirement?
• A retail chain with 200 stores is planning Cisco SD-WAN and the architect must assign Validator for initial authentication, Manager for configuration, Controller for route distribution, and WAN Edge for forwarding. The rollout needs zero-touch onboarding and centralized policy. Which SD-WAN plane assignment correctly aligns each component with its primary function?
• An enterprise has a headquarters campus, three large hybrid branches needing voice and ERP, plus small sales offices and bursty cloud analytics. Budget is tight and MPLS renewals are expensive. Which WAN connectivity selection balances performance, cost, and cloud agility across on-premises, hybrid, and cloud sites?
• A retailer must bring up 80 new branch SD-WAN routers with limited on-site skill, centralized templates, and secure identity verification before they join the overlay. Which SD-WAN onboarding and provisioning approach meets zero-touch deployment with authentication requirements?
• A retail chain with 120 small stores needs connectivity where wired broadband takes 60 days to install, POS traffic is low bandwidth but critical, and outages must fail over automatically with centralized policy. Which 4G/5G transport design as primary or backup best meets the retail requirement?
• A logistics company must onboard 150 WAN Edge routers to Cisco SD-WAN with minimal site visits, strict serial-number authorization, and centralized templates applied after authentication. Some sites sit behind NAT with no public reachability. Which SD-WAN onboarding and provisioning approach meets zero-touch, authorization, and NAT needs?
• A multinational manufacturer has factories in three continents, most traffic flows to two regional data centers, inter-factory traffic is rare, and IT wants simple control with predictable failover. Which SD-WAN control plane and overlay design best matches this traffic pattern?
• A logistics company runs DMVPN over broadband with a hub in each region and 200 spokes needing direct spoke-to-spoke voice without hairpinning through hubs. Future summarization at hubs is planned. Which DMVPN phase design provides spoke-to-spoke behavior with route summarization support?
• A bank is adopting SD-WAN across branches and must ensure controller authentication, encrypted overlay traffic, and integrity validation even if underlay networks are untrusted. Which SD-WAN built-in security design provides control, data, and device protection together?
• An enterprise runs a headquarters data center, two regional hubs, and new SaaS-heavy branches that need direct cloud access with low latency, while legacy client-server apps remain centralized and require predictable performance. Which WAN connectivity design for on-premises, hybrid and cloud sites best balances the needs?
• A bank is designing Cisco SD-WAN for 80 branches over public internet to carry cardholder data, requiring authenticated devices, encrypted transport, and isolated payment traffic from guest traffic. The board wants native overlay protections before adding perimeter firewalls. Which built-in SD-WAN security capability should the designer specify to satisfy these transport needs?
• A retailer has a hub in Dallas and 120 small stores needing direct voice traffic between stores, dynamic spoke addresses on broadband, and no permanent spoke-to-spoke tunnels to save router memory. Which DMVPN phase and spoke-to-spoke behavior best fits these dynamic-mesh requirements?
• A retailer connects 40 stores to headquarters over the Internet, needing EIGRP routing updates and multicast inventory feeds over encrypted paths while accepting extra overhead. A second project needs simple site-to-site encryption for unicast file transfer only. Which IPsec versus GRE-over-IPsec tradeoff guides the design?
• A retailer has a headquarters data center, 30 branch stores needing direct cloud SaaS access, and a new AWS-hosted inventory app that must scale for holiday bursts. Branches suffer backhaul delay, the data center needs stable high capacity, and cloud workloads must burst without new circuits. Which WAN connectivity mix should the designer recommend for on-premises, hybrid and cloud needs?
• A 300-user branch uses two Cisco SD-WAN routers sharing one LAN switch block, with voice, data, and guest VLANs, dual Internet transports, and a need for seamless gateway failover without host reconfiguration. Routing must stay simple and loop-free toward the overlay. Which LAN-side design with VRRP and routing should the designer select?
• A global manufacturer has headquarters in Chicago, regional hubs in London and Singapore, and 150 branches needing direct branch-to-branch collaboration, including between branches in different regions. Leadership wants resilient control, localized breakouts, and efficient overlay paths without hairpinning everything. Which SD-WAN control-plane and overlay design best fits these considerations?
• A retailer plans SD-WAN for 500 stores with dual transports per store, centralized policy, and no single failure taking down management or overlay establishment. Growth to 1000 sites is expected within two years. Which SD-WAN high availability and scale design should the architect propose to sustain resilient growth?
• A bank runs a private MPLS core to 60 branches with low-latency voice needing any-to-any encryption without per-tunnel overhead and centralized key policy. Internet backhaul is prohibited for this traffic. Which GET VPN group key model fits the private transport requirement?
• A retail bank is adding SD-WAN routers in parallel to existing branch routers at 80 sites. Tellers need sub-second failover between LAN gateways, and branch prefixes must fail over without redistribution loops. Which LAN-side design at SD-WAN sites meets these routing needs?
• A logistics firm connects two data centers over the Internet, needs encrypted voice plus dynamic routing with multicast for RP discovery, and must minimize overhead for small packets. Which IPsec versus GRE-over-IPsec tradeoff best meets this secure transport need?
• A multinational has headquarters in three continents, each with dual data centers and hundreds of branches that mostly access regional resources but occasionally need inter-region collaboration. The WAN must limit control overhead, keep latency low, and avoid hairpinning all traffic centrally. Which SD-WAN control-plane and overlay design should the designer propose for these regional traffic patterns?
• A manufacturer with 80 spokes on DMVPN needs hub-routed traffic today but wants direct spoke-to-spoke voice for new plants without permanent full mesh, using multipoint GRE and NHRP. Which DMVPN phase behavior should the designer specify to enable on-demand direct spoke tunnels?
• A retail chain with 120 stores needs any-to-any inventory traffic with provider-managed routing, guaranteed latency, and isolation from Internet threats. The provider offers MPLS L3VPN and the team also considered Internet IPsec overlay. Which enterprise VPN choice best fits this MPLS versus overlay requirement?
• A bank runs any-to-any voice between branches over private MPLS, must encrypt without new tunnel headers or routing changes, and needs scalable rekey to all encryptors at once. Which site-to-site VPN group key design fits the private transport constraint?
• A manufacturing firm connects a Detroit plant to a Monterrey plant over the public internet. Engineers must carry EIGRP routing updates plus legacy non-IP protocols for shop-floor controllers, while security mandates encrypted transport for all inter-site traffic. Which site-to-site VPN tradeoff decision correctly balances multiprotocol support with encryption overhead?
• A regional retail chain connects 45 stores with Cisco SD-WAN over broadband and LTE using centralized control and IPsec overlay tunnels. Stores need prioritized voice for POS support, fair sharing for inventory and guest Wi-Fi, and weekly training video that headquarters sources as IP multicast. Underlay loss and latency vary by site. Which SD-WAN QoS and multicast design consideration best fits this fabric?
• A retail chain is deploying SD-WAN at 80 stores, each with two edge routers connecting to a single LAN switch stack for POS and staff VLANs. The stores need sub-second gateway failover without routing flaps, plus loop-free handoff toward the overlay. Which LAN-side design using VRRP and routing best fits these store requirements?
• A national logistics firm with 250 branches needs dual-transport SD-WAN with no single controller failure isolating sites and room to add 150 more sites without redesign. Which SD-WAN high availability and scale design meets dual-transport redundancy for these branches?
• A bank operates 60 MPLS branches carrying voice that cannot tolerate tunnel overhead or added latency. Security policy requires any-to-any encryption without spoke-to-hub tunnels, and the WAN provider guarantees no packets ever traverse the public internet. Which GET VPN group key design best satisfies low-overhead encryption over trusted private transport?
• A logistics firm with 60 sites on private carrier links needs isolated routing for voice, inventory, and guest, wants the carrier to manage VPN membership and QoS, and lacks staff to run overlay tunnels. Which enterprise VPN design best matches private transport and outsourcing?
• A branch clinic depends on a single router and ISP link for telehealth and loses all connectivity during any access failure. The redesign must survive a device, link, or provider failure without extending fate-sharing. Which high-availability branch design best limits this failure-domain requirement?
• A media company connects three studios over SD-WAN and must prioritize live video, limit file-transfer bandwidth during shows, and deliver one-to-many streams efficiently across the overlay. Which SD-WAN QoS and multicast design serves prioritized video over the fabric for these studios?
• A logistics firm with 80 sites wants any-to-any connectivity, minimal internal routing burden, and easy addition of new warehouses without reconfiguring every router. The carrier offers point-to-point Ethernet and a shared MPLS backbone with per-customer tables. Which WAN service choice best addresses routing ownership and scaling for this growth?
• A bank is rolling SD-WAN to 300 branches with dual transports, needing controller survival during outages, deterministic failover for edge tunnels and a clear plan for device and site growth. The design must avoid single points of failure without oversubscribing control capacity. Which high availability, redundancy and scale approach fits?
• A regional bank connects a headquarters and five branches in one metro area, requiring any-to-any Layer 2 connectivity for clustered servers and seamless VLAN extension. The carrier offers E-Line and E-LAN services with strict storm-control needs. Which Metro Ethernet service type fits the multipoint bridging requirement?
• A bank with 120 branches needs any-to-any connectivity and strict traffic separation for branches and partners, and security policy mandates customer-controlled end-to-end encryption and direct Internet backup. The carrier offers a managed MPLS L3VPN with its own routing and no encryption. Which enterprise VPN comparison best guides the choice between MPLS L3VPN and overlay VPN?
• A manufacturer connects its data center to two different ISPs for high availability and must keep voice and ERP outbound on the low-latency ISP during normal operation while allowing inbound customers to reach its public prefix through either ISP if one fails. Which multihomed BGP inbound and outbound path control design provides resilient high availability?
• A manufacturer uses Cisco SD-WAN across MPLS and Internet underlays with voice, ERP, and regional video feeds needing prioritization and efficient delivery. Which QoS and multicast design suits traffic treatment over the SD-WAN fabric?
• A retail chain has 80 small stores on a single ISP link with LTE backup, while two distribution centers use two ISPs and dual routers to sustain outages and maintenance. Store outages remain isolated but cost must stay low. Which WAN resilience comparison guides single-homed versus dual-homed branch design for failure domains?
• A logistics firm with 60 sites needs any-to-any branch routing, centralized Internet breakout, and minimal in-house routing operations. The carrier offers a managed MPLS Layer 3 VPN and a Layer 2 VPLS service. Scale and staffing drive the decision. Which WAN choice correctly reflects routing ownership and scaling for this enterprise?
• A city government must connect a data center to three service yards for a shared permit system needing multipoint bridging, plus a separate point-to-point backup link for nightly replication between two sites. The carrier proposes Metro Ethernet options. Which Metro Ethernet service design fits the bridging and point-to-point needs?
• A regional retailer has 60 small branches with one MPLS link and one router, where a recent carrier cut isolated six stores for hours and the business now wants bounded failure domains and sub-minute recovery for high-revenue sites while keeping small sites cheap. Which single-homed versus dual-homed branch design best balances resilience and cost?
• A healthcare system must interconnect two data centers 80 km apart with sustained 100 Gbps encrypted replication, deterministic latency, and full control of wavelengths for future growth. Packet services share fate and oversubscribe at peak. Which DWDM and leased optical design choice addresses the capacity requirement?
• A branch office uses a primary MPLS path and a backup Internet VPN with dynamic routing, and tellers cannot tolerate long blackholes when the primary degrades silently without interface down. Designers need fast failure detection and automatic path switchover. Which backup connectivity and failover trigger design best meets availability needs?
• A regional headquarters multihomes to two ISPs with its own public ASN, needing primary outbound use of ISP-A and inbound preference for critical application prefixes via ISP-A while keeping ISP-B as backup without causing transit between providers. Which BGP path control design balances inbound and outbound traffic?
• A logistics firm with 60 sites needs any-to-any connectivity, fast new-site turn-up, and minimal in-house routing operations while retaining control of internal address planning. Which Layer 2 VPN versus MPLS Layer 3 VPN choice fits routing ownership and scaling?