Important Nokia 4A0-100 Exam Questions

Answer: D

Explanation:

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

Answer: A

Explanation:

In a typical MPLS/VPN service architecture:

PE (Provider Edge) router: Directly connects to the customer edge (CE) device.

P (Provider) router: Only forwards MPLS-labeled packets, does not touch customer routes.

LSR (Label Switch Router): General term, can be either PE or P depending on placement.

Correct Answer: A -- PE

It interfaces with CE devices and runs customer routing protocols (e.g., OSPF, BGP).

Nokia MPLS and VPN Guide -- PE vs P Role

Nokia SRA Study Guide -- PE-CE and Core Router Design

Answer: C

Explanation:

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

Answer: D

Explanation:

A MAC address (Media Access Control address) is a 48-bit identifier typically expressed in six groups of two hexadecimal digits (e.g., 00-20-60-CE-2B-28). It consists of two key parts:

OUI (Organizationally Unique Identifier) -- The first 24 bits (or first 3 octets, e.g., 00-20-60) are assigned by the IEEE to hardware manufacturers. This identifies the vendor or manufacturer.

Device Identifier (NIC Specific) -- The remaining 24 bits (e.g., CE-2B-28) are assigned uniquely by the vendor to each device/interface.

So in the address 00-20-60-CE-2B-28:

00-20-60 is the OUI

CE-2B-28 is the device-specific portion

Thus, the correct answer is D. 00-20-60.

IEEE MAC Address Standard (IEEE 802)

Nokia IP Networking Fundamentals Study Guide -- Chapter: 'Ethernet Addressing'

Answer: B

Explanation:

A hub is a physical layer (Layer 1) networking device used to connect multiple Ethernet devices in a network. Unlike switches or routers, hubs do not inspect or process frame headers. Instead, they perform a simple task:

Receive a signal (electrical or optical) on one port

Replicate that signal identically to all other ports

This means the hub does not examine Layer 2 (MAC addresses) or Layer 3 (IP addresses) and does not perform intelligent forwarding. It merely broadcasts all incoming traffic to every other connected device, often resulting in high collision domains and poor efficiency.

Option A describes a repeater, not a hub.

Option C describes a switch (Layer 2 device).

Option D describes a router (Layer 3 device).

Option B is correct: A hub does not inspect headers and replicates traffic blindly.

Nokia IP Networking Fundamentals Study Guide -- Chapter: 'Network Devices and OSI Model'

CompTIA Network+ and Cisco CCNA foundational guides (for universally accepted hardware behavior)