What is a Service Set Identifier?

Quick Definition: Service Set Identifiers, more commonly known as SSIDs, are the names associated with wireless networks. SSIDs help users join the correct networks or connect to the correct Bluetooth devices.

You have definitely used at least one SSID, or Service Set Identifier, in your lifetime. As a matter of fact, you’re probably using one right now as you read this article — but do you know what they are and how they work? 

An SSID is what networks and devices use to advertise themselves. They can be just about anything within certain guidelines, which we will discuss later in this article. 

How Does SSID Work in Wireless Standards and Technologies?

As computers became more connected and even wireless, the Institute of Electrical and Electronics Engineers (IEEE) began establishing and improving standards for wireless connectivity. 

Connections became more reliable, transmission speeds became faster, and wireless connections have increased the distances at which they can broadcast. This is why you may be able to maintain a reliable connection to your home network as you walk away from the house, scrolling on your phone. 

We need SSIDs to connect to devices and networks, and for the same reason, we need URLs to reach various websites — it’s easier to remember a word or phrase than a string of random letters and numbers. 

Even better, SSIDs, like URLs, can include context in their naming convention. We’ll discuss naming conventions and standards in greater detail in the next section.

It is important to note that SSIDs can impact security. For example, a hotel naming one of its networks something like “Admin Control Network” might be a little too enticing for potential hackers. 

A coffee shop naming one of its networks “payment terminal network” might be great from a network segmentation perspective, but it’s also going to tell attackers exactly which network to target to access financial information. 

Network administrators can choose to hide the SSID, which means they won’t be broadcast at all, but they will still be discoverable to certain tools, many of which are often used by hackers. Hiding the SSID may just raise interest among hackers because what’s cooler than finding something you weren’t supposed to?

What are the Components of SSID Naming Conventions?

Let’s talk about SSID naming conventions. An SSID can be any string up to 32 characters consisting of letters, numbers, dashes, and underscores. SSIDs are case sensitive, so it’s important to confirm you are joining the correct network, especially if you’re joining a public network such as a coffee shop, as attackers are known to set up rogue access points to intercept your data. 

You may be joining “coffee-shop Wi-Fi” when the shop’s actual network is “Coffee_Shop_WiFi” which means someone in or near the coffee shop is looking for victims. 

While there are no official rules for SSID naming conventions, there are some best practices to ensure SSIDs provide enough context to be both user-friendly and easy to work with from a networking perspective. 

Ideally, SSIDs find the right balance between being just descriptive enough and not being too descriptive. SSIDs can even include the bandwidth, such as either 2.4 GHz or 5 GHz, to make it easier to determine which network certain devices should join. 

We’ll list some examples of good SSIDs below:

• “CoffeeShopStaff”: Using your SSID to differentiate between staff, guest, and other networks is a great way to help keep users on the correct network. 

• “Pack-n-Print 2.4 GHz”: Including the bandwidth within the SSID helps identify which network might be best for connecting devices like security cameras and printers. 

• “Neighborhood Dental Guest”: Naming your SSID the same name as your business is great when there are multiple networks within the same range, as it helps customers connect to the correct network and not some other network that just so happens to be within range.

We’ll also look at some examples of some SSIDs whose names aren’t as helpful.

• “Store Wi-Fi”: Imagine you’re connecting to a network at the mall, where there are plenty of stores to choose from. Can you tell which store this network belongs to? 

• “Patient Database Network”: This SSID is far too descriptive for a medical facility network since it could help attackers identify the network with highly sensitive information.

• “8Tp1-Linksys”: This SSID might be fine for your home network, but it is far from user-friendly for customers and employees in a corporate, commercial, or retail environment. 

While the general consensus is that fewer SSIDs are better, your organization may benefit from having separate SSIDs for various reasons, such as separating guests from the corporate network. Most modern networking equipment will handle multiple SSIDs, but you should confirm with your equipment.

How to Use SSID via the Installation of Wireless Access Points (WAPs)

There are several factors to consider when preparing to install one or more Wireless Access Points, more commonly referred to simply as WAPs or access points. 

Two of the main considerations are environmental factors and usage. If you are installing access points for a large building with several users, you will want to install more access points and ensure they can provide enough coverage to carry a reliable connection as users move from one area to another. 

Let’s look at an example of installing access points for a college campus. 

Using the SSID “Student Network,” you want to ensure students can walk from one end of campus to the other while staying connected. Consider factors such as how many devices will be connecting to any one access point at a single time and how many simultaneous connections your equipment can handle. This will determine the number of access points you will need to deploy. 

Also, consider environmental factors that may disrupt connectivity such as physical obstructions like other buildings or trees. If the campus has a large open space, such as a quad, you will need to figure out how to provide coverage for the areas farthest from other access points. 

You may be able to deploy WAPs with a significant range, or you may opt to deploy additional access points throughout the quad by mounting them to structures such as light poles. You may also opt for some form of point-to-point equipment to bridge any gaps in coverage. 

One final consideration is the physical requirements for deploying access points. You’ll need a power supply, a switch or router, and physical cables to connect it all together. This will almost certainly impact how and where you deploy access points within your environment. Adequate planning is crucial to the successful deployment of wireless access points in any environment.

How to Configure SSID on Wireless Access Points

Configuring your network device’s SSID will vary by its make and model. You may be able to connect to a graphical user interface (GUI) or use the command line interface (CLI), but either option should allow you to manipulate the SSID name and settings. 

Regardless of your device, you should be able to modify settings, including the SSID name, authentication method (including username and password), what VLAN (virtual local area network) the SSID should be assigned to, and whether the SSID should be broadcast. 

Ideally, each SSID will map to a dedicated VLAN, so if you haven’t already created separate VLANs for each SSID, it’s best to go ahead and do so prior to configuring new SSIDs. Remember, the goal with multiple SSIDs is to segment traffic, so you will also want to restrict access based on the purpose of each VLAN and SSID combination. 

For example, a guest or customer network should not be able to access internal corporate resources, and internal corporate networks might want to restrict access to specific external resources, such as inappropriate or dangerous websites. 

As we mentioned earlier in the article, it’s a good idea to name your SSIDs in a way that indicates what that network might be used for. Although it might sound counterintuitive, hiding a network’s SSID often leads to more trouble than broadcasting the name openly.

Troubleshooting SSID Configuration Issues

Networking will inevitably require troubleshooting at some point, but thankfully, it doesn’t have to be complicated. Some of the common issues you will experience when dealing with SSIDs and wireless networking include not seeing the SSID as an available network, connecting to the network but not having Internet access, and unreliable connections. 

If you know there should be a network SSID visible, but it’s not showing as available or you're experiencing unreliable connections, take these steps: 

• Verify that your wireless device has WiFi and/or Bluetooth enabled: If WiFi/Bluetooth is enabled and you still don’t see an available SSID, try turning it off and back on again. 

• Restart the access point: If you’re within range and you still don’t see the SSID available, the access point may need to be restarted.

• Verify encryption and authentication are correct: If you’re able to connect but still don’t have network access, verify that the encryption and authentication information is correct and supported by the device you’re trying to connect to. If needed, try removing that network from your device history and reconnecting to it. 

• Reduce distance: Unreliable connections on a particular network can occur when you're too far from the access point, or environmental factors such as trees or other buildings may limit the optimal range. 

• Use load balancing: Too many simultaneous connections and improper load balancing can cause issues. We’ll discuss this in the next section, but network engineers and administrators should be implementing some form of network load balancing to help distribute traffic among access points in a given area. 

How to Monitor and Manage SSID Performance

If you’re curious about network performance or need additional help troubleshooting network issues, several types of packet analysis tools are available. These tools provide detailed information about transmission speeds, packet size, source and destination IP addresses, protocol, and more. 

There is so much data to cover when discussing packet analysis that it could be an entire course, and it is! Check out our Wireshark course to learn about one of the more common packet analysis tools in the industry.

Load balancing can help improve network performance by evenly distributing connections across one or more network devices. In networks with multiple wireless access points, load balancing occurs when a device attempts to connect. 

If the access point can handle additional connections, it will allow them. If not, it will either send the request to other nearby access points or simply deny the connection request, forcing the device to rebroadcast the request. The exact methods by which load balancing works depend on factors such as how they are implemented, the network size, and the quantity of access points. 

Conclusion

SSIDs, or Service Set Identifiers, are the names network devices use to advertise themselves to other devices looking to establish a connection. It’s how you know which WiFi network or Bluetooth speaker your phone should connect to.

SSIDs exist in just about every network, from corporate offices to your home router. They can be attached to their own VLAN, and they can be almost any name, so long as it is 32 characters or fewer. That name can be indicative of what the network is used for and who it belongs to. 

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