Nokia 4A0-100 Exam Questions Instant Access

Question 1

Which of the following statements about the VPWS service on a Nokia 7750 SR is FALSE?

AVPWS is a point-to-point service.

BVPWS emulates a layer-2 connection between two customer sites.

CVPWS does not perform MAC learning.

DVPWS encapsulates layer-2 frames into IP datagrams.

Answer : D

VPWS (Virtual Private Wire Service) on Nokia 7750 SR:

Emulates a Layer 2 point-to-point connection.

Does not require MAC learning, unlike VPLS.

Uses MPLS encapsulation, not IP datagrams for transport.

Option D is FALSE -- VPWS uses MPLS labels, not IP encapsulation.

Nokia 7750 SR Service Router Guide -- VPWS Overview

Nokia SRA Study Guide -- Chapter: Layer 2 Services

Question 2

Which of the following is required if devices on different VLANs wish to communicate with each other?

AThey can communicate if they are connected to the same switch.

BThey can communicate if they are in the same broadcast domain.

CThey can communicate if there is a router to connect them.

DThey cannot communicate.

Answer : C

A Virtual Local Area Network (VLAN) is a logical separation of devices at Layer 2, even if those devices are connected to the same physical switch. Each VLAN forms its own broadcast domain, and traffic cannot cross from one VLAN to another without Layer 3 routing.

Option A is incorrect -- devices on the same switch but in different VLANs still cannot communicate directly.

Option B is incorrect -- VLANs explicitly create separate broadcast domains.

Option D is technically incorrect -- communication is possible with the right setup.

Option C is correct -- to enable communication between different VLANs, a router or a Layer 3 switch with inter-VLAN routing capability is required.

This process is called inter-VLAN routing, and it's a fundamental task in enterprise networks using VLANs.

Nokia IP Networking Fundamentals Study Guide -- Chapter: 'LAN Segmentation and VLANs'

Cisco CCNA and CompTIA Network+ -- Inter-VLAN Routing Concepts

Question 3

Which of the following statements about a physical router interface is FALSE?

AIt is associated with a port.

BIt is used to connect to other routers or to customer hosts.

CIt can be associated with an IP address and with a prefix length.

DIt can be of type system or loopback.

Answer : D

In Nokia SR OS:

A physical interface refers to a physical port on the router (e.g., port 1/1/1).

It can be configured with IP addresses, associated with services (e.g., IES, VPRN), and connects to other routers or customer devices.

System and loopback interfaces are logical interfaces, not physical.

Option D is FALSE, because a physical interface cannot be of type 'system' or 'loopback' --- those are virtual/logical interfaces in the Nokia router architecture.

Nokia SRA Study Guide -- Chapter: ''Interfaces and Ports''

Nokia SR OS Interface Configuration Guide

Question 4

From a customer's perspective, how does a VPRN service operate?

AAll sites are connected to a single wire.

BAll sites are connected to a switched network.

CAll sites are connected to a routed network.

DAll sites are connected to the Internet.

Answer : C

A VPRN (Virtual Private Routed Network) provides a Layer 3 VPN service over a service provider's network.

Each customer site connects to a PE router.

Sites are connected via a routed network using separate routing instances.

Customer routers see routed connectivity, as if connected to their own private WAN.

Option C is correct -- VPRN provides routed connectivity between sites.

Nokia Service Routing Guide -- Chapter: VPRN

Nokia SRA Guide -- Service Types and Operation

Question 5

Which of the following statements about the IP forwarding process on a router is TRUE?

AIt uses the routing table to find a match for the source IP address.

BIt uses the routing table to find a match for the destination IP address.

CIt uses the ARP table to find a match for the source MAC address.

DIt uses the ARP table to find a match for the destination MAC address.

Answer : B

When a router forwards a packet, it performs the following operations:

Looks up the destination IP address in the routing table to determine the next hop or egress interface.

Uses the ARP table to resolve the MAC address of the next-hop IP.

Option A is incorrect -- source IP is not used for route lookup.

Option C is incorrect -- routers don't resolve the source MAC.

Option D is partially true, but routing begins with the routing table, making B the most accurate.

Nokia IP Fundamentals Study Guide -- Chapter: ''IP Packet Forwarding''

RFC 1812 -- Requirements for IP Routers

Question 6

What is the purpose of a broadcast IP address?

ATo provide an address that refers to all the IP devices in a subnetwork.

BTo provide an address that refers to a specific group of devices in a network.

CTo provide an address that refers to a group of devices with the same IP address in different layer-2 domains.

DTo provide an address that refers to a single device on a given subnetwork.

Answer : A

A broadcast IP address is used to send a message to all devices on a specific IP subnet. This address is the highest address in the subnet (i.e., all host bits set to 1).

Example: In 192.168.1.0/24 broadcast is 192.168.1.255.

It is used for purposes like ARP requests or DHCP discovery.

Option A is correct -- refers to all hosts in a subnet.

Option B refers to multicast, not broadcast.

Option C might refer to anycast, which is different.

Option D describes a unicast address.

Nokia IP Fundamentals Study Guide -- Chapter: 'IP Addressing and Broadcast Communication'

RFC 919 -- Broadcasting Internet Datagrams

Question 7

Which of the following statements about IP route summarization is FALSE?

AIt divides a customer IP address pool into smaller portions, each of which is assigned to a different subnet.

BIt reduces the size of the routers' forwarding tables.

CIt improves scalability of the network.

DIt increases routing advertisement stability.

Answer : A

Route summarization (a.k.a. supernetting) is the process of combining multiple contiguous subnets into a single summarized route, which:

Reduces routing table entries

Enhances scalability and efficiency

Minimizes instability by localizing route changes

Option A is false because it describes subnetting, not summarization. Summarization works in the opposite direction -- combining smaller routes into a larger one.

Nokia IP Routing Guide -- Chapter: ''Route Summarization Techniques''

Cisco CCNA -- IP Routing Concepts

Nokia IP Networks and Services Fundamentals 4A0-100 Exam Questions