Two employees have created a direct wireless connection between their laptops with no access point present. Which type of 802.11 wireless topology have they formed?

Introduction / Context:
Wireless LANs based on IEEE 802.11 can be deployed in several topologies, including basic service sets, extended service sets, and independent basic service sets. Many certification exams test your ability to recognize when a particular scenario describes a centralized access point based design versus a direct peer to peer ad hoc network between wireless clients.

Given Data / Assumptions:

• Two workers are using wireless laptops.
• They have established communication directly between the laptops.
• No access point or wireless controller is mentioned in the scenario.
• The question asks which topology has been created by this direct connection.

Concept / Approach:
A basic service set (BSS) uses an access point as the central device that all wireless clients associate with. An extended service set (ESS) consists of multiple BSSs connected through a distribution system such as a wired Ethernet backbone. An independent basic service set (IBSS) is different: it is an ad hoc network in which wireless clients communicate directly with one another without any access point. The key phrase in the scenario is that the workers connected their laptops directly, which immediately suggests an IBSS.

Step-by-Step Solution:
1. Identify whether an access point is present in the scenario. The text explicitly states that the laptops connect directly, and no access point is named.2. Recall that a BSS always includes a single access point that forms the center of that wireless cell.3. Recall that an ESS is built from multiple BSSs and therefore still depends on one or more access points connected by a distribution system.4. Recognize that an IBSS is defined as an independent basic service set, commonly referred to as ad hoc mode, in which stations communicate peer to peer without infrastructure.5. Because the laptops are communicating directly with each other and no infrastructure device is present, this scenario exactly matches an IBSS.

Verification / Alternative check:
If you configure two laptops in ad hoc mode in a lab, you will see that they form a temporary network without requiring an access point. Tools such as wireless configuration utilities will label this as ad hoc or peer to peer. In contrast, when connecting to a typical office Wi-Fi, you always see an access point or wireless router as the device you associate with, which is characteristic of a BSS or ESS, not an IBSS.

Why Other Options Are Wrong:
Option A, BSS, is incorrect because a BSS requires an access point. Option B, SSID, is not a topology at all; it is simply the name string used to identify a wireless network. Option D, ESS, describes multiple BSSs tied together by a distribution system, again requiring one or more access points, which are absent in this scenario.

Common Pitfalls:
Candidates sometimes confuse the term IBSS with BSS and forget that the presence or absence of an access point is the key difference. Another common issue is thinking that any two clients on the same Wi-Fi network are in ad hoc mode, when in fact they may both be associated to the same access point in a BSS or ESS. Always look for phrases like direct connection with no access point to identify an IBSS.

Final Answer:
Independent Basic Service Set (IBSS, ad hoc mode)