Physical and Logical Infrastructure Requirements

In this sample chapter from CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide: Designing & Implementing Cisco Enterprise Wireless Networks, you will learn how to determine physical infrastructure requirements including AP power, cabling, switch port capacity, mounting, and grounding. You will also learn how to determine logical infrastructure requirements such as WLC/AP licensing requirements based on the type of wireless architecture.

This chapter discusses the following topics:

Physical Infrastructure Requirements: Powering an access point with Power over Ethernet (PoE) has several variants, including delivering power directly from a switch or through a power injector. However, PoE itself comes in several flavors that have cabling infrastructure dependencies. This section discusses the main types of PoE, including PoE, PoE+, UPoE, and UPoE+, and the types of cables that support them. In addition, as modern 802.11 standards begin to push beyond 1Gbps, traditional Ethernet connections over twisted pair cable is no longer enough to support the maximum performance capabilities of the access point. This section discusses the improved performance characteristics of mGig and the network requirements necessary. This section also discusses AP mounting and grounding strategies.

Logical Infrastructure Requirements: This section discusses the logical elements of a wireless network, such as the communication flow of the CAPWAP control and data channels as they traverse the network, and their implications on the underlying physical infrastructure. In addition, this section discusses controller and AP licensing mechanisms.

This chapter covers the following ENWLSD exam topics:

• 2.1 Determine physical infrastructure requirements such as AP power, cabling, switch port capacity, mounting, and grounding

• 2.2 Determine logical infrastructure requirements such as WLC/AP licensing requirements based on the type of wireless architecture

The focus of wireless network design often revolves around the RF aspects of the deployment—and indeed, as discussed throughout this book, RF design is the foundation of any successful wireless network and almost always involves a robust site survey. However, there are key infrastructure components that are just as important in any wireless design exercise. These are generally grouped into two major classes: the physical infrastructure components and logical infrastructure components.

The physical infrastructure includes components of the physical networking gear. This involves the physical gear itself, as well as how the access points are cabled, powered, mounted, and even grounded. This design aspect goes far beyond just the access points and the controller. For example, if a switch is used to deliver PoE to an AP, the switch must be able to accommodate the power requirements of the AP. If it cannot, either the AP will not power on or certain capabilities (such as secondary radios) will not work.

Additionally, the reachability of the APs over standard Ethernet cabling becomes a design criterion as distances from the switch grow and as higher data rates are used. When the existing cable plant cannot support the distances demanded by the placement of APs, suboptimal AP placement may be used, which in turn may lead to poor RF coverage. Understanding the design requirements of the physical infrastructure is a crucial aspect of developing a successful wireless design.

The second infrastructure aspect is the logical network—in other words, the path the communication flows take through the network, regardless of the underlying physical infrastructure. Controller-based wireless networks use CAPWAP (Control And Provisioning of Wireless Access Points), both as a control channel as well as to encapsulate client data traffic, effectively tunneling client traffic directly from the AP to the controller, and vice versa. This gives the logical appearance that the APs and controller are Layer 2 adjacent, when in reality they may be traversing many hops of the underlying physical network. Understanding the behavior and function of these logical elements introduces important considerations when developing the infrastructure side of the wireless design.

This chapter focuses on these two infrastructure aspects, beginning with the physical infrastructure and followed by the logical infrastructure.

“Do I Know This Already?” Quiz

The “Do I Know This Already?” quiz allows you to assess whether you should read this entire chapter thoroughly or jump to the “Exam Preparation Tasks” section. If you are in doubt about your answers to these questions or your own assessment of your knowledge of the topics, read the entire chapter. Table 4-1 lists the major headings in this chapter and their corresponding “Do I Know This Already?” quiz questions. You can find the answers in Appendix D, “Answers to the ‘Do I Know This Already?’ Quizzes and Review Questions.”

Table 4-1 “Do I Know This Already?” Section-to-Question Mapping

1. An access point has been deployed with full features, including dual radios and hyperlocation. The AP requires 38W of power. Which of the following Power over Ethernet capabilities should you recommend be used?

   1. PoE

   2. PoE+

   3. UPOE

   4. UPOE+

2. A group of new Wi-Fi 6 (IEEE 802.11ax) APs has just been installed in a building to replace the older Wi-Fi 5 (802.11ac wave 1) APs. What is a design consideration you need to be aware of when deploying the physical infrastructure?

   1. Mounting of the new APs to reflect changes in the 802.11ax RF radiation pattern.

   2. An increase of power will be required. The switch will need to be upgraded to support either UPOE or UPOE+.

   3. The number of Wi-Fi 6 APs required will be less than the older APs thanks to better performance and coverage patterns.

   4. The switch connected to the APs may need to be upgraded to support mGig.

3. For security reasons, the building facilities team abides by a policy that no devices (APs included) may be visible from the office floor. As an alternative, the network team is looking to deploy the APs above the suspended ceiling. What should they be aware of?

   1. Positioning APs above the ceiling will result in significant RF degradation, so a new site survey may be required.

   2. This configuration is not supported by Cisco.

   3. Specialized mounting brackets will be needed.

   4. The APs should be positioned as close to the T-bar rails as possible.

4. When deploying higher throughput wireless technologies in Local mode, what design aspect must be considered related to possible oversubscription of the physical infrastructure?

   1. Uplink capabilities of the access switch should be considered.

   2. Physical connections between the access switch and AP should be considered.

   3. Performance of the backbone network connecting to the controller should be aligned with overall wireless performance demands.

   4. Performance capabilities of the controller should be considered.

   5. All of the above.

5. What interfaces on a physical controller (such as the WLC 5520) are used to communicate to key services such as ISE and CMX? (Choose two.)

   1. The service port

   2. The Management Interface

   3. The virtual port

   4. Any LAN interface port on the controller

   5. The AP-Manager interface

6. Which Cisco wireless licensing model involves pooling of licenses?

   1. Right-to-Use (RTU) licensing

   2. Perpetual licensing

   3. Term licensing

   4. Product Activation Key (PAK) licensing

   5. Smart Licensing

Foundation Topics

Physical Infrastructure Requirements

The physical infrastructure of a wireless network includes all physical elements, including the access points, controllers, switches and routers, and any other physical network devices that facilitate communication between the wireless users and the network they are trying to access. In addition to networking devices, the physical infrastructure includes power delivery, cabling, mounting, and grounding of access points.

PoE and PoE+

Power over Ethernet (PoE) is a widely used infrastructure technology that allows DC power to be provided to an endpoint over a twisted pair Ethernet cable. Power is passed from power sourcing equipment (PSE), such as a PoE-capable switch, over the existing twisted pair Ethernet cable that carries data communications to powered devices (PDs), such as IP phones, video cameras, wireless access points, point-of-sale machines, access control card readers, LED luminaires, and many more. Through the use of PoE, external powering of endpoints is not required, thus greatly reducing the cost and effort required to deploy electrical power throughout the infrastructure. Typically, for a company to deploy electrical cabling in the ceiling requires a certified electrician to perform the task, whereas the deployment of Ethernet cables (which can run PoE) can be done by anyone, thus greatly simplifying the job of deploying access points wherever they need to go.

The power requirements of endpoints varies based on their power consumption requirements, which is typically a function of the physical function, application, and complexity of the device. For example, basic IP phones might draw approximately 6W of power, whereas contemporary LED lighting fixtures can draw up to 50W for routine operation. Wireless APs draw different power levels depending on which features are enabled and how many radios are concurrently active. For example, the Cisco 3800 typically draws ~30W with all features turned on.

Power delivery over Ethernet twisted pair is based on the IEEE 802.3af (2003) standard and delivers up to 15.4W of DC power per port of the PSE; however, due to power dissipation in the cable, only 12.95W of this is available to the PD.

After the initial introduction of PoE in 2003, endpoints were soon demanding greater power than 802.3af could deliver. Thus, in 2009, IEEE 802.3at was standardized, known as PoE Plus (PoE+). PoE+ delivers up to 30W of DC power per port, ensuring 25.5W of power to a PD due to power dissipation.

In both of these cases, PoE delivers power over two of the four twisted pairs of Class D/Category 5e or better cabling. The PSE uses only signal pairs—that is, the pairs formed by pins 1 and 2 and pins 3 and 6—to transport power from the PSE to the PD and leaves the spare pairs idle (consisting of pins 4 and 5 and pins 7 and 8). Note that PoE does not affect the network performance of Ethernet links to the PD.

UPOE and UPOE+

In recent years the enterprise workspace has continued to evolve, resulting in increasing numbers of devices and workloads converging onto the IP network. This has fueled increasing demand for higher PD power draw, far in excess of what PoE and PoE+ can offer (more than 25.5W).

To meet this demand, Cisco has developed extended PoE capabilities, including Universal PoE (UPOE), capable of delivering 60W per port, and Universal PoE Plus (UPOE+), which is capable of delivering up to 90W per port. Note that while PoE and PoE+ have been standardized by the IEEE, UPOE and UPOE+ are Cisco proprietary. In 2018, the IEEE defined 802.3bt as a standard to deliver up to 90W (sometimes referred to as PoE++).

The network’s ability to deliver higher levels of power to endpoints has, in turn, significantly expanded the PoE-capable endpoint landscape. Thanks to these higher PoE capabilities, a wide variety of devices with higher power requirements can now be powered over Ethernet without requiring separate electrical wiring. These include video endpoints, LED lighting fixtures, digital signage, compact switches, and, of course, larger and more robust access points.

802.3bt, UPOE, and UPOE+ all use the same cabling standard as PoE/PoE+; however, instead of delivering power over just two of the twisted pairs, these higher power embodiments of PoE utilize all four twisted pairs of standard Ethernet cabling (Category 5e or better). They does this by using two PSE controllers to power both the signal pairs and the spare pairs. Figure 4-1 presents the difference between PoE/PoE+ and Cisco UPOE/UPOE+.

In the case of PoE, PoE+, or UPOE, the minimum Ethernet cable type is Category 5e. In the case of UPOE+, Category 6a is required at a minimum. Regardless of the method of power over Ethernet, the maximum cable distance remains the same at 100 meters.

It is also important to note that support for the type of PoE desired depends on the capabilities of the Ethernet switch. For example, older switches may only support PoE/PoE+; however, modern switches (such as the Catalyst 9300) support UPOE, and certain higher-end switches support UPOE+ (such as the Catalyst 9400).

Table 4-2 summarizes the various PoE options available to power network devices.

Table 4-2 A Summary of Power over Ethernet Standards and Capabilities

Power Injectors

PoE delivered by an access switch is a natural choice to power APs in most wireless deployments. This greatly reduces the wiring required and allows flexible AP placement throughout a building. That being said, there are still use cases where PoE delivered by the access switch is not practical, and power injectors must be considered. For example, there may be places where the switch simply doesn’t support the necessary PoE mode, or perhaps the switch has no available PoE-capable ports, or it may even have a severely limited power budget due to too many other PDs. In some cases, certain APs with full features enabled may have greater power demands than a legacy PoE switch can offer. In these situations, using a power injector is a simple and often appealing alternative.

Power injectors generally have two Ethernet inputs: one connected to the upstream switch and another connected to the PD (that is, the access point). The power injector is also plugged into a power source via the 48V DC power supply, which then injects power into the two pairs, supporting PoE and PoE+.

Cisco power injectors are offered in two form factors. The first variant supports copper Category 5e or better cables both on the input and output (connected to the switch and to the access point). In this case, maximum cable distance from switch to AP remains at 100 meters—that is, the power injector does not function as a repeater and increase the maximum transmission distance over the twisted pair cable.

The second variant is a fiber optic link between the switch and the power injector. In this case, the power injector functions as a media converter and injects power onto the twisted pair cable that connects to the access point. Using single-mode fiber allows the power injector to be placed up to 2 kilometers from the switch, making it a practical option for places where the AP is far away, such as large factories, warehouses, and other places with sparse wiring closets.

Figure 4-2 illustrates the two power injector options for Cisco access points.

MultiGigabit

With increasing performance speeds of 802.11ac Wave 2 (Wi-Fi 5) and more recently 802.11ax (Wi-Fi 6), the maximum theoretical wireless throughput of an access point is pushing well beyond the 1Gpbs capability of traditional Ethernet access, potentially making the single wired uplink between the AP and switch a chokepoint.

To solve this problem, Cisco has championed the development of MultiGigabit (mGig) technology that delivers speeds of 2.5Gbps, 5Gbps, or 10Gbps on existing cables. The NBASE-T Alliance (created in 2014) initially led the standards development of MultiGigabit over Ethernet, but it was eventually merged with the Ethernet Alliance in April 2019 and is now marketed as mGig by Cisco. In addition to traditional Ethernet speeds over Category 5e cable, Cisco mGig supports speeds of 2.5Gbps, 5GBps, and 10Gbps. The technology also supports PoE, PoE+, and Cisco UPOE.

The main characteristics mGig are as follows:

• Variable speeds: Cisco mGig technology supports auto-negotiation of multiple speeds on switch ports (100Mbps, 1Gbps, 2.5Gbps, and 5bps on Cat 5e cable, and up to 10Gbps over Cat 6a cabling).

• Flexible cable types: mGig supports a wide range of cable types, including Cat 5e, Cat 6, and Cat 6a or above.

• PoE power: The technology supports PoE, PoE+, and UPOE (up to 60W) for all the supported speeds and cable types, providing access points with additional power for advanced features, such as hyperlocation and modularity.

Figure 4-3 illustrates the use of mGig between a capable access switch and an access point.

Cisco 3800 and 4800 series access points (802.11ac Wave 2) and Cisco Catalyst 9100 series APs (Wi-Fi 6 / 802.11ax) support Cisco mGig technology at speeds of 2.5Gbps and 5Gbps. This technology protects the investment in the cabling infrastructure, allowing for newer and faster wireless technologies to be transported over the same physical Ethernet infrastructure without becoming a chokepoint.

To summarize, Table 4-3 illustrates the different mGig speeds and supported cable categories.

Table 4-3 Supported mGig Speeds with Associated Cable Categories

Mounting Access Points

Wireless deployments often require a variety of different AP mounting options depending on the physical attributes and accessibility of each location. To address this, Cisco offers several different mounting bracket options. In addition, several third-party vendors provide mounting brackets and enclosures for less common scenarios.

This section discusses the three most common options for mounting Cisco APs:

• Ceiling and wall mounting

• Mounting below ceiling tiles

• Mounting above ceiling tiles

Ceiling and Wall Mounting Access Points

When mounting on a horizontal or vertical surface, you can use one of the two standard mounting brackets:

• AIR-AP-BRACKET-1: This mounting option features a low profile, making it a popular choice for ceilings.

• AIR-AP-BRACKET-2: This is a universal mounting bracket that is often used if the AP will be mounted on the wall or placed in a NEMA (National Electrical Manufacturers Association) enclosure.

Figure 4-4 illustrates the two mounting bracket options.

When wall mounting is desired, the installer should understand that walls can be a physical obstacle to the RF signal; therefore, maintaining 360-degree coverage can be compromised by the wall if the AP is not placed correctly. If the wall is an outside wall and/or if the goal is to transmit the signal in a narrower beam (such as down a food aisle in a grocery store), a directional antenna may be a better choice, assuming the external antenna model of an AP is used.

In most cases, it is recommended to avoid wall-mounting APs with internal antennas, as the antenna orientation of these APs is optimally designed for ceiling mount, providing RF coverage in a 360-degree pattern to the space below the floor. If the AP is wall mounted, it is recommended to use either a right-angle mount (where the AP is still oriented downward) or external antennas that project the RF energy into the space as expected. For this reason, it is generally recommended to mount indoor APs on the ceiling rather than on a wall.

Mounting Access Points Below a Suspended Ceiling

To facilitate mounting APs below a suspended ceiling, specialized mounting brackets are available that clip onto the rail of a T-bar ceiling. Figures 4-5 and 4-6 illustrate the mounting bracket for these types of ceilings.

Mounting Access Points Above the Ceiling Tiles

Mounting access points below the ceiling tiles is the preferred option; however, in some cases, wireless engineers may prefer to position the access points so that nothing is visible from the ground, or there may be a building facilities policy that prohibits any device from attaching to the suspended ceiling. Mounting above the ceiling tiles may also be preferred for aesthetic reasons, or it may be done as a way to reduce theft in vulnerable areas (such as public hotspots where theft or damage may be a problem). In such circumstances, Cisco indoor access points (such as the Catalyst 9120i and 9120e) are rated for installation in the plenum area above the suspended ceiling (UL-2043), allowing them to be attached to the T-bar mesh but suspended above the tile.

Figure 4-7 illustrates a mounting schematic for an AP above the ceiling tiles.

When mounting the AP above the ceiling tiles, it is important to remember that the tiles must not be conductive, as this would have a degrading effect on the RF performance of the AP and may interfere with wireless LAN features that depend on uniform coverage, such as voice and location services. Additionally, the AP should be mounted as close to the center of the ceiling tile as possible and away from any possible obstructions that could interfere with RF performance.

Grounding and Securing Access Points

Grounding is not always required for indoor installations because access points are classified as low-voltage devices and do not contain internal power supplies. However, electrical grounding is always recommended for outdoor access points. It is always best to check with local electrical standards to determine if grounding is necessary.

Although grounding is not mandatory for most indoor access points, it is required in certain scenarios. For example, in unground scenarios such as mining operations, indoor access points that are mounted too close to an electromagnetic source of interference may reboot suddenly or suffer hardware damage (such as APs deployed near a fluorescent light). This may occur even if the AP is not physically touching the electrical source but is just in close proximity to the electromagnetic source of interference. Grounding this access point or the mounting bracket helps prevent this issue from occurring. It is recommended that a certified electrical technician verify whether the installation requires grounding.

Figure 4-8 shows an outdoor access point with the grounding connector.

Logical Infrastructure Requirements

The path in which traffic flows through a network appears differently depending on your point of view. For example, from a network technician’s point of view, a packet travels through the network in a hop-by-hop path across each physically connected device. However, from a wireless end user’s perspective, if traffic is tunneled in an overlay, the user may only see one hop between an access point and the controller, when in reality numerous physical hops were encountered along the path of the underlying network. This is the difference between the physical and logical network.

Traffic also flows differently depending on the deployment model chosen: autonomous access points act as direct links between the wireless and the wired sides of the network, whereas centrally controlled access points in Local mode must forward all wireless client traffic to the controller over an encapsulated CAPWAP tunnel. In FlexConnect mode, some WLANs may be locally switched at the AP, while others may be centrally switched on the controller.

The following section will explore some of the logical infrastructure characteristics of a wireless network, including flow of the CAPWAP channels, logical connections to services supporting the wireless infrastructure such as AAA and DHCP servers, and finally the licensing options that are available to support the wireless deployment.

CAPWAP Flow

CAPWAP is a logical network connection between access points and a wireless LAN controller. CAPWAP is used to manage the behavior of the APs as well as tunnel encapsulated 802.11 traffic back to the controller.

CAPWAP sessions are established between the AP’s logical IP address (gained through DHCP) and the controller’s management interface. (In older versions of AireOS, the CAPWAP session terminated on the ap-manager interface; however, this has been changed to the management interface in more recent versions of AireOS.)

Whether in Local or FlexConnect mode, CAPWAP sessions between the controller and AP are used to manage the behavior of the AP. When in Local mode, CAPWAP is additionally used to encapsulate and tunnel all wireless client traffic so that it can be centrally processed by the controller. CAPWAP sessions use UDP for both the control and data channels, as follows:

• CAPWAP Control Channel: Uses UDP port 5246

• CAPWAP Data Channel: Uses UDP port 5247 and encapsulates (tunnels) the client’s 802.11 frames

• Figure 4-9 illustrates the different CAPWAP channels between an AP and a controller.

If there is a firewall or router with access control lists (ACLs) along the logical path between the AP and the controller, it is important to ensure that rules are in place to allow both the CAPWAP control and data channel ports through the firewall so that the AP and controller are able to communicate correctly. A complete list of recommended firewall rules can be found here:

https://www.cisco.com/c/en/us/support/docs/wireless/5500-series-wireless-controllers/113344-cuwn-ppm.html

As the number of APs grows, so does the number of CAPWAP tunnels terminating on the controller. Figure 4-10 illustrates the logical connection of multiple CAPWAP sessions over the physical infrastructure.

Considering that all APs in Local mode use CAPWAP to tunnel 802.11 client traffic back to the controller, an important design criterion related to traffic load must be considered. With 802.11ac Wave 2, the maximum theoretical throughput of a single AP is ~1.3Gbps. 802.11ax (Wi-Fi 6) promises even greater speeds, with the theoretical throughput expected to be in excess of 10Gbps from a single AP (based on multiple streams). Considering the CAPWAP data channel will need to support increasing levels of data throughput (not to mention framing and packet overhead), the demands of the logical infrastructure have a direct correlation to capabilities of the underlying physical infrastructure. In this vein, careful analysis must be taken at various places in the network to determine if the performance demands of the wireless network can be met. This includes the following design aspects:

• The physical connection between the AP and the access switch (evaluate if mGig is required)

• An estimation of oversubscription of the uplink of the access switch to the network

• Backbone capacity of the core network

• WAN connection speeds if the controllers are centralized and APs are in Local mode

• Network access speeds to the controller

• Performance capabilities of the controller

From a design perspective, the theoretical maximum bandwidth consumption of an AP is usually never attained. However, if enough APs are simultaneously generating a high volume of traffic, a controller can quickly run out of resources. Take the example of a controller that is licensed for 500 APs. If these were all Wi-Fi 6 APs passing an excessively high volume of traffic, the aggregate bandwidth capacity of the physical connection to the controller could be quickly exhausted, meaning more controllers wither fewer APs may be necessary.

Performance issues at the controller may manifest in two possible ways: (1) the underlying network’s ability to aggregate all CAPWAP data traffic and forward it without oversubscription of the physical links connected to the controller, and (2) the controller’s own performance limitations in being able to process the volume of data it is receiving.

If either of these two cases emerges, certain design changes can be considered. One change is decentralizing and splitting the function of the controllers such that less data is being managed by a single controller. Another option is to simply reduce the number of APs that each controller manages. If decentralizing the controllers is preferred, the roaming path must also be considered. While roaming between APs connected to the same controller is simple and should be seamless, if clients roam to an AP connected to a different controller, the roaming path will involve intercontroller communication and greater network complexity.

Another area where oversubscription may be an issue is on the access switch where the APs are physically connected. Take the example of an access switch with several dozen APs connected with mGig, all running Wi-Fi 6. If the clients associated to these APs are generating large amounts of aggregate data, the throughput demands could quickly exhaust even a 10Gbps uplink from the access switch. Thus, it is imperative to assess not only how many APs are being deployed (and how many of each type), but also careful calculation must be made to determine if the uplink capacity of the access switches can accommodate expected traffic demands, including how much oversubscription is acceptable. If it is found that the oversubscription rate is excessive, then either multiple uplinks will be needed (which requires port channeling) or a fewer number of APs should be deployed on each access switch.

AAA and DHCP Services Logical Path

Another area where the logical path requires careful consideration is the path between the controller and the key services, such as the AAA and DHCP servers. Services such as AAA (ISE), DHCP, DNS, MSE/CMX, DNA Spaces, and many more may be placed at locations throughout the network that have firewalls protecting them. Understanding the logical path between these services will often require opening of firewall rules for the service to interface with the controller.

As with CAPWAP, the controller’s management interface is used to communicate with AAA servers, as well as a host of other services, including MSE/CMX, directory servers, other controllers, and more.

For DHCP, controllers proxy communication to the DHCP sever on behalf of clients using the controller’s IP address in the VLAN associated to the WLAN of those clients.

Table 4-4 summarize the ports that must be open to allow the controller to communicate with key services.

Table 4-4 Summary of AAA and DHCP Services and Ports Used for the Wireless Infrastructure

Licensing Overview

In addition to purchasing the controller itself, Cisco wireless deployments require licenses to activate the use of the access points. The following section provides a summary of how Cisco wireless controllers and APs are licensed.

Cisco AireOS wireless controllers support two types of licensing models: Right to Use (RTU) licensing and Smart Licensing.

Right to Use Licensing

Right to Use (RTU) licensing is an honor-based licensing mechanism that allows AP licenses to be enabled on AireOS controllers (such as the 5520 and 8500 series controllers) with end user license agreement (EULA) acceptance. The RTU license scheme simplifies the addition, deletion, and transfer of AP licenses and does not require specialized license keys or product activation key (PAK) licenses.

With RTU licensing, there are three types of licenses:

• Permanent licenses: The AP count is programmed into nonvolatile memory at the time of manufacturing. These licenses are not transferable from one controller to another.

• Adder access point count licenses: These are additional licenses that can be activated through the acceptance of the agreement. These licenses are also transferable between controllers and types of AireOS controllers.

• Evaluation licenses: These are used for demo and/or trial periods and are valid for 90 days, and they default to the full capacity of the controller. The evaluation license activation is performed through the AireOS command-line interface (CLI).

Smart Licensing

In addition to the RTU licensing model, AireOS controllers support Smart Licensing. Smart Licensing is a cloud-based flexible licensing model that simplifies the way licenses are managed across an organization rather than on a per-controller basis. The intent of Smart Licensing is to make it easier to manage and deploy Cisco software licenses from a central repository without having to track how licenses are used on individual products.

Instead of using product activation keys (PAKs) or RTU licensing, Smart Licenses establish a central pool of AP software licenses in a customer-defined Smart Account that can be used across the enterprise and across all controllers or APs. Smart Licensed products self-register upon configuration and activation with a single token, removing the need to register products individually with separate PAKs or to accept a license agreement. Thus, instead of licensing each individual controller for the number of APs that the administrator anticipates it to manage, the pool of licenses can be shared across all controllers in the enterprise and be used as needed. This approach has a distinct advantage over legacy licensing models by greatly simplifying and optimizing the use of licenses.

In the RTU model, one controller may be licensed for far more APs than it is currently managing, whereas another controller may not have enough licenses for what it needs. Smart Licensing eliminates the overhead and waste by simply putting all AP licenses in a central pool that can be managed and budgeted for as the need arises. As new APs are added or moved across the organization, the administrator no longer needs to determine the current license count on a per-controller basis—only the Smart Licensing pool of AP licenses needs to be monitored and maintained. This not only provides better utilization of licenses but also it makes it easier to procure and deploy licenses as the organization grows.

To use Smart Licensing, the following steps must be followed:

Step 1. Create a Smart Account:

1. Create a Smart Account at the following link: https://software.cisco.com/software/company/smartaccounts/home#accountcreation-account.

2. Go to Cisco Software Central at software.cisco.com.

3. An editable profile appears.

4. An email is automatically sent to the customer Smart Account administrator.

Step 2. Register the Cisco controller using the Smart Account.

1. For existing customers, deposit existing licenses, if any, into the Smart Account.

2. For a new purchase, purchase a Cisco DNA license for access points connecting to the Cisco Catalyst controller.

Step 3. Configure the license level on the controller, as desired.

Summary

This chapter focused on both the physical and logical infrastructure requirements of wireless LAN deployments. In this chapter you have learned the following:

• The various PoE options available for different APs as well as the capabilities and function of each PoE mechanism.

• How higher-performance wireless standards, such as 802.11ac Wave 2 (Wi-Fi 5) and 802.11ax (Wi-Fi 6), can be supported through mGig

• AP mounting options, including above and below a tile ceiling mount and wall mount options

• The importance of grounding APs in certain situations

• The need to consider the logical path and its impact on the underlying physical infrastructure, including the CAPWAP control and data channels as well as AAA and DHCP services

• Different types of licensing models available for different Cisco Wireless LAN controllers, including RTU licensing and Smart Licensing, which is as a method of pooling licenses across the enterprise

References

For additional information, refer to these resources:

Cisco Enterprise Wireless—Intuitive Wi-Fi Starts Here: https://www.cisco.com/c/dam/en/us/products/collateral/wireless/nb-06-wireless-wifi-starts-here-ebook-cte-en.pdf

Catalyst 9120 Access Point Deployment Guide: https://www.cisco.com/c/en/us/products/collateral/wireless/catalyst-9100ax-access-points/guide-c07-742311.html

Network World—Best Practices When Cabling an Access Point: https://www.networkworld.com/article/3290459/what-are-the-best-practices-when-cabling-for-wi-fi.html

Power over Ethernet: Empowering Digital Transformation: https://www.cisco.com/c/dam/en/us/products/collateral/switches/catalyst-9000/nb-06-upoe-plus-wp-cte-en.pdf

Transform the Workspace with Cisco MultiGigabit Ethernet White Paper: https://www.cisco.com/c/en/us/solutions/collateral/enterprise-networks/catalyst-multigigabit-switching/white-paper-c11-733705.html

Cisco Smart Licensing Overview: https://www.cisco.com/c/dam/en/us/products/collateral/software/smart-accounts/q-and-a-c67-741561.pdf

Exam Preparation Tasks

As mentioned in the section “How to Use This Book” in the Introduction, you have a few choices for exam preparation: the exercises here, Chapter 18, “Final Preparation,” and the exam simulation questions in the Pearson Test Prep Software Online.

Review All Key Topics

Review the most important topics in this chapter, noted with the Key Topic icon in the outer margin of the page. Table 4-5 lists these key topics and the page numbers on which each is found.

Table 4-5 Key Topics for Chapter 4

Define Key Terms

Define the following key terms from this chapter and check your answers in the glossary:

• PoE

• PoE+

• UPOE

• UPOE+

• Power Sourcing Equipment (PSE)

• Powered Device (PD)

• Power Injector

• Cisco MultiGigabit

• Right to Use (RTU)

• End User License Agreement (EULA)

• Smart Licensing