Extended Service Set


The Extended Service Set (ESS) is a concept in wireless networking that denotes a collection of connected Basic Service Sets (BSS). BSS is the basic building block of a wireless Local Area Network (LAN), and ESS allows users to roam freely within the area covered by these BSSs without losing connection. These ESSs ensure seamless communication as users move within the areas served by different access points.


The phonetics of “Extended Service Set” would be:Extended: ɪkˈstɛndɪd Service: ˈsɜːrvɪs Set: sɛt

Key Takeaways

Three Main Takeaways About Extended Service Set:

  1. Definition: An Extended Service Set (ESS) is a networking concept that involves the combination of two or more Basic Service Sets (BSS). This enables the creation of a bigger network where users can move around without losing connection, creating a seamless wireless environment.
  2. Components: ESS is mainly composed of Access Points (APs) and stations. Stations refer to devices such as laptops, computers, or smartphones. The APs are connected through a Distribution System which can be wired, wireless, or a combination of both.
  3. Advantages: ESS allows for greater mobility within a network as devices can move from one AP area to another without losing their connection. Additionally, due to its extended range coverage, it provides a more reliable and wider area of connectivity.


Extended Service Set (ESS) is a crucial term in wireless networking technology, particularly in Wi-Fi communication. ESS is critical because it allows the networking of multiple access points (APs) together, facilitating seamless mobility for users moving around within the areas covered by the APs without losing the connection. In an ESS, all access points share the same Service Set Identifier (SSID) and allow devices to roam freely within the coverage area without needing to re-establish connections or experiencing service disruption. This technology is especially important in large environments like office buildings, campuses, or hospitals where extended network coverage and uninterrupted Wi-Fi connectivity are essential. Through ESS, these environments can maintain comprehensive, reliable, and seamless wireless network service.


Extended Service Set (ESS) is a critical term used in wireless networking, specifically in the context of Wi-Fi deployment. Its primary purpose is to facilitate the creation of a larger coverage area for wireless networks. It achieves this by permitting the interconnection of multiple Access Points (APs), which then form a single large network. The ultimate aim is to allow clients to move seamlessly from one network to another without experiencing any disruptions in their service, a property known as roaming.ESS was designed to overcome the limitations of Basic Service Sets (BSS) – individual access points with their associated devices – that couldn’t support user mobility across a broad area. Using ESS, devices such as laptops or mobile phones can maintain consistent wireless connectivity while moving around a larger space, like a university campus, office building or hospital. This feature is possible because all access points within an ESS share the same Service Set Identifier (SSID) and channel, allowing a device to switch access points without changing network settings or losing connection.


Extended Service Set (ESS) is a concept used widely in the networking field, especially concerning wireless LAN technologies like Wi-Fi. It refers to a set of one or more interconnected Basic Service Sets (BSSs).1. College Campus Network: A vast university campus could have multiple buildings — each building equipped with its own wireless access point. To ensure students can move around the campus while maintaining a stable Wifi connection, the network is set up as an Extended Service Set. The different wireless access points are united together to form one bigger network.2. Shopping Malls: Large shopping malls often provide Wi-Fi service to shoppers. Each floor or department could have different basic service sets, i.e., different networks. These are interconnected to form an ESS, enabling users to maintain internet connection as they move between the areas in the mall.3. Corporate Offices: In a corporate office setup spread across multiple floors or departments, each zone may have its own network for efficiency and ease of management. But to ensure seamless connection for employees moving within the campus, these networks are interconnected as an ESS. This allows for uninterrupted connection, making it easier for employees to carry laptops from meeting to meeting without losing connectivity.

Frequently Asked Questions(FAQ)

**Q1: What is an Extended Service Set (ESS)?**A: An Extended Service Set (ESS) is a network architecture used in wireless networking that includes one or more interconnected Basic Service Sets (BSSs).**Q2: Is there any difference between Basic Services Set (BSS) and Extended Service Set (ESS)?**A: Yes, there is. A BSS is a single wireless network node, while an ESS is a combination of two or more BSSs linked together to form a larger network.**Q3: What components or devices are used in an Extended Service Set (ESS)?**A: An ESS utilizes devices like Access Points (APs) and wireless stations such as laptops or mobile phones. The APs in an ESS are interconnected via a Distribution System (DS) which can be wired or wireless.**Q4: What is the major advantage of using an Extended Service Set?**A: The major advantage of using an ESS is that it allows users to roam freely within the area of the service set and maintain their wireless network connection.**Q5: Can we connect ESS to the internet?**A: Yes, an ESS is typically connected to the internet through a router, allowing devices within the ESS to access internet services.**Q6: How secure is an Extended Service Set (ESS)?**A: The security of an ESS depends on the security measures that are in place, which can include encryption protocols like WEP, WPA, or WPA2. However, like any wireless network, they can be vulnerable if proper security measures are not taken.**Q7: Can one device connect to multiple ESS networks?**A: Yes, a device can connect to multiple ESS networks, but it can only be associated with one network at a time.**Q8: Is there a limit to how many BSSs can be included in an ESS?**A: Technically, there is no specific limit to how many BSSs can be included in an ESS. The main limiting factor would likely be the capacity of the Distribution System (DS) connecting the different BSSs. **Q9: What is the purpose of a Distribution System in an ESS?**A: The Distribution System (DS) is used for forwarding frames to their destination within the ESS, allowing communication between different BSSs.**Q10: How does data transmission work in an ESS?**A: In an ESS, a device (station) sends data to an Access Point (AP) which then transmits it through the Distribution System (DS) to the intended destination. If the destination is within the same network, the AP sends the data directly. If the destination is on a different network, the data is forwarded via the DS to the appropriate AP.

Related Finance Terms

  • EAP (Extensible Authentication Protocol)
  • BSSID (Basic Service Set Identifier)
  • SSID (Service Set Identifier)
  • WLAN (Wireless Local Area Network)
  • Wi-Fi Alliance

Sources for More Information


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