Free Nokia SRA Composite Exam Practice Questions

Sample Practice Questions

Try these 10 sample questions from the Nokia SRA Composite Exam practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1What information does BGP primarily exchange between routing systems?

   1. A.Reachable IP networks and associated path informationCorrect answer: A
   2. B.Every link's state in a shared interior routing area
   3. C.Hosts' Ethernet addresses and switch-port locations
   4. D.Interface error counters and physical cable diagnostics

   Explanation: RFC 4271 states, "The primary function of a BGP speaking system is to exchange network reachability information with other BGP systems." This describes BGP reachability exchange; link-state flooding, MAC learning and physical diagnostics serve different purposes.

   Reference: RFC 4271 — A Border Gateway Protocol 4 — Section 3, Summary of Operation

2. 2In the Nokia service model, which information identifies a service access point (SAP)?

   1. A.A remote AS number and BGP community
   2. B.A local port and encapsulation valueCorrect answer: B
   3. C.A route target and VPN label
   4. D.A router ID and MPLS tunnel metric

   Explanation: Nokia lists "a SAP identifying a port and encapsulation value". A SAP identifies the local service attachment, rather than an AS policy, VPN route attribute or tunnel metric.

   Reference: Nokia SR OS Services Overview — Global Service Entities — Basic service configuration elements

3. 3Two VPN customers both advertise 10.20.0.0/16. What is the purpose of adding different route distinguishers to those prefixes?

   1. A.To select the set of VRFs permitted to import the route
   2. B.To identify the provider's IGP path for the VPN packet
   3. C.To make the VPN-IPv4 routes distinct in BGPCorrect answer: C
   4. D.To choose the outgoing service label for the destination

   Explanation: RFC 4364 says the RD allows creation of "distinct routes to a common IPv4 address prefix." It distinguishes overlapping VPN-IPv4 routes; it is not an encryption mechanism or the import policy itself.

   Reference: RFC 4364 — BGP/MPLS IP Virtual Private Networks — Section 4.1, The VPN-IPv4 Address Family

4. 4Which network conditions specifically impair the real-time applications discussed in the Integrated Services architecture?

   1. A.Variable queueing delays and congestion lossesCorrect answer: A
   2. B.Stable propagation delay and available spare capacity
   3. C.Fixed packet sizes and separate forwarding classes
   4. D.Predictable scheduling and reserved bandwidth

   Explanation: The source states, "real-time applications often do not work well across the Internet because of variable queueing delays and congestion losses." Real-time traffic requires attention to delay variation and loss; predictable resources and scheduling are remedies rather than these impairments.

   Reference: RFC 1633 — Integrated Services in the Internet Architecture — Section 1, Introduction

5. 5Which BGP attribute records the autonomous systems through which an advertised route has passed?

   1. A.NEXT_HOP
   2. B.AS_PATHCorrect answer: B
   3. C.LOCAL_PREF
   4. D.MULTI_EXIT_DISC

   Explanation: RFC 4271 explains that AS_PATH "identifies the autonomous systems through which routing information carried in this UPDATE message has passed." NEXT_HOP identifies a forwarding next hop; the other attributes express preferences rather than the traversed AS sequence.

   Reference: RFC 4271 — A Border Gateway Protocol 4 — Section 5.1.2, AS_PATH

6. 6Two distributed services use the same far-end Nokia router. Which statement about sharing a service distribution point (SDP) is correct?

   1. A.An SDP is dedicated to exactly one service
   2. B.Each service type requires an exclusive SDP
   3. C.More than one service can be bound to an SDPCorrect answer: C
   4. D.An SDP can be shared only by local services

   Explanation: Nokia states, "An SDP can have more than one service bound to it." The SDP is therefore not inherently exclusive to a single service or service type; the question concerns distributed, not purely local, connectivity.

   Reference: Nokia SR OS Services Overview — Global Service Entities — Configuring an SDP — SDP characteristics

7. 7A PE has received a VPN-IPv4 route. What Route Target condition makes it eligible for import into a particular VRF?

   1. A.The route's RD must equal the VRF's interface address
   2. B.The route must have no extended community attributes
   3. C.Every export target must match every local import target
   4. D.At least one route target must match a VRF import targetCorrect answer: D

   Explanation: RFC 4364 requires "some Route Target" shared by the route and the VRF import set. A single matching target establishes eligibility, although route-selection rules still determine installation; an RD match or matching every target is not required.

   Reference: RFC 4364 — BGP/MPLS IP Virtual Private Networks — Section 4.3.1, The Route Target Attribute

8. 8What delivery assurance do Nokia's best-effort forwarding classes provide?

   1. A.A reserved minimum rate for each individual application
   2. B.A fixed maximum end-to-end transit delay
   3. C.No delivery guarantees for their packetsCorrect answer: C
   4. D.Lossless delivery whenever a packet is marked BE

   Explanation: The source states, "The best-effort forwarding classes have no delivery guarantees." A BE classification alone does not reserve throughput, bound delay or promise lossless delivery.

   Reference: Nokia SR OS Quality of Service Guide — Section 2.2.3, Best-effort classes

9. 9An SR OS router cannot establish its BGP transport connection because a firewall blocks the protocol's listening port. Which destination transport and port must the firewall permit?

   1. A.UDP port 179
   2. B.TCP port 646
   3. C.TCP port 179Correct answer: C
   4. D.UDP port 520

   Explanation: RFC 4271 states, "BGP listens on TCP port 179." Therefore TCP/179 is the required transport endpoint; changing to UDP or an LDP/RIP port does not establish this BGP connection.

   Reference: RFC 4271 — A Border Gateway Protocol 4 — Section 3, Summary of Operation

10. 10In an LDP-signaled VPLS, an unknown source MAC address first arrives over a pseudowire. What association should the receiving PE learn?

    1. A.The destination MAC to the arriving pseudowire
    2. B.The source MAC to every pseudowire in the service
    3. C.The source MAC to the destination's local attachment
    4. D.The source MAC to the arriving pseudowireCorrect answer: D

    Explanation: RFC 4762 says that an unknown source MAC "needs to be associated with the PW". This is source-address learning in the data plane, not learning the destination or creating an external routing neighbor.

    Reference: RFC 4762 — VPLS Using LDP Signaling — Section 4.2, Address Learning