200-901 Question #399: Real Exam Question with Answer & Explanation

Question

Drag and Drop Question Drag and drop the functions from the left onto the networking devices on the right. Answer:

Explanation

This drag-and-drop question tests the understanding of fundamental functions performed by common networking devices such as switches, routers, firewalls, and load balancers.

Approach. The correct approach is to match each networking function to the device that primarily performs that role:

1. 'forwards by default' should be dragged to 'switch'. A network switch operates at Layer 2 (data link layer) and forwards Ethernet frames based on MAC addresses. Once it learns a MAC address-to-port mapping, it forwards traffic for that MAC address out the correct port by default. If it doesn't know the destination MAC, it floods the traffic to all ports (except the source port).

2. 'distributes unicast traffic over devices' should be dragged to 'load balancer'. A load balancer's primary function is to distribute incoming unicast client requests across multiple backend servers or resources to ensure high availability and optimal resource utilization.

3. 'uses traffic inspection to make forwarding decisions' should be dragged to 'firewall'. A firewall inspects network traffic (at various layers, including packet headers and sometimes payload) against a set of security rules to determine whether to allow, deny, or block the traffic, effectively making a forwarding decision based on security policy.

4. 'distributes multicast traffic over devices' should be dragged to 'router'. Routers are responsible for routing multicast traffic between different network segments (subnets) using protocols like PIM (Protocol Independent Multicast). While switches handle multicast within a segment using IGMP snooping, the distribution 'over devices' (implying different networks) is a router's function.

Common mistakes.

• common_mistake. A common mistake might be confusing the roles of a switch and a router, or misattributing specific traffic management functions. For example, dragging 'forwards by default' to 'router' would be incorrect because a router's primary job is to route packets between different networks, not simply 'forward by default' within the same network segment like a switch. Dragging 'distributes unicast traffic over devices' to 'router' or 'switch' would be wrong because while they forward unicast traffic, the term 'distributes over devices' implies the intelligent load distribution provided by a load balancer. Attributing 'traffic inspection' to a switch or router instead of a firewall would be incorrect as firewalls specialize in deep packet inspection and rule-based forwarding/blocking for security purposes, beyond basic routing or switching decisions.

Concept tested. Core functions and distinctions of fundamental networking devices: Switches, Routers, Firewalls, and Load Balancers.

No community discussion yet for this question.