Authentic Nokia Certification Exam 4A0-100 Questions Answers

Abroadcast IP addressis used tosend a message to all deviceson a specific IP subnet. This address is thehighest 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 Brefers tomulticast, not broadcast.

Option Cmight refer toanycast, which is different.

Option Ddescribes aunicastaddress.

Address summarization(also called route aggregation) is a technique used in IP routing to combine several contiguous network prefixes into asingle summarized route.

This reduces the number of routes that need to be advertised and stored in routing tables, improvingscalability and performance.

Option A is correct– summarization replaces many specific routes with a single aggregated route.

Option Brefers to best path selection (not summarization).

Option Cis incorrect; duplicate advertisements are still processed and filtered based on metrics.

Option Dis unrelated to summarization; directly connected routes are always advertised unless specifically filtered.

Ahubis aphysical layer (Layer 1)networking device used to connect multiple Ethernet devices in a network. Unlike switches or routers, hubs donot 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 hubdoes not examine Layer 2 (MAC addresses) or Layer 3 (IP addresses)and doesnot perform intelligent forwarding. It merelybroadcasts all incoming traffic to every other connected device, often resulting inhigh collision domainsand poor efficiency.

Option Adescribes arepeater, not a hub.

Option Cdescribes aswitch(Layer 2 device).

Option Ddescribes arouter(Layer 3 device).

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