APs are the devices that connect to the LAN, providing wireless access to the network. Wireless clients communicate with APs to access LANs or WLANs, as shown in Figure 1-1. Figure 1-1. Wireless Clients Connect to the LAN via an AP
APs serve either as the core of an all-wireless network or as a point of connection between the wired and wireless networks. In addition, APs can be located throughout an organization to ensure access at remote locations in a facility. Cisco features several models of APs. The model that fits best for your organization depends on a number of factors, which include:
The following sections examine the Cisco Aironet APs, with specific details of each model. Cisco Aironet 1100 SeriesThe Aironet 1100 AP (shown in Figure 1-2) includes a single radio and supports the 802.11g protocol. 802.11g is backward compatible to support the earlier 802.11b protocol. The most important distinction between 802.11b and 802.11g is the data rate802.11b provides 11 Mbps, whereas 802.11g allows up to 54 Mbps. Figure 1-2. Cisco Aironet 1100 AP
The 802.11b device can be upgraded to 802.11g capability. The 802.11g version allows wireless networks to leverage their investment on existing 802.11b equipment. It is also capable of 54-Mbps speeds with any new equipment. The Aironet 1100 AP allows the use of up to 16 virtual LANs (VLANs) and quality of service (QoS) functions. The AP also features hot standby and load balancing, which allow an organization to deploy intelligent network services and ensure network reliability and availability. VLANs allow an organization to segment its users into their own discrete LANs. Thus, individual LAN policies, services, security levels, and QoS levels can be established for different groups of users. The Cisco Wireless Security Suite manages the security for the Aironet 1100 AP. This product is based on the 802.1X standard for port-based network access, and makes use of Extensible Authentication Protocol (EAP) for user-based authentication. EAP and other security mechanisms are explained in more detail in Chapter 4, "Wireless Security." The Aironet 1100 uses the Cisco Internetworking Operating System (IOS), which provides common command-line feel for Cisco veterans. Alternately, the device can be managed through a browser-based graphical user interface (GUI), such as the one shown in Figure 1-3. Figure 1-3. The Aironet 1100 Can Be Managed Using a Browser-Based InterfaceThe Aironet 1100 AP can be used as a single point of access to the WLAN, or several APs can be placed throughout the site to provide wireless access anywhere on the premises. Cisco offers various pieces of hardware to mount the device to the ceiling, the wall, or the edge of a cubicle. Aironet 1130AG Series APThe 1130AG AP builds on the functionality and utility of the Aironet 1100 Series AP. This AP uses two built-in radios (802.11a and 802.11g) for optimal coverage and usability. Shown in Figure 1-4, the 1130AG AP employs two internal antennas for omnidirectional coverage. The ring on the front of the device changes color, depending on its current state. For example, when nothing is associated, the ring glows a pale green. When one or more devices have associated, it glows blue. If an error occurs, it glows red. Figure 1-4. Cisco Aironet 1130AG AP
Because the AP employs both 802.11a and 802.11g radios, it affords a capacity of up to 108 Mbps. In addition, because both radios are used, it can handle 15, nonoverlapping channels (12 from the 802.11a radio and 3 from the 802.11g radio). In a future firmware upgrade, this capacity will increase to 22 channels. This will ensure less interference with neighboring WLANs and fewer transmission errors. Note Because the AP uses an 802.11g radio, existing 802.11b legacy devices are supported. For example, multiple 1130AGs can be installed in a ceiling to provide continuous coverage as users roam from room to room in a facility. As this device is somewhat of an "entry-level" model, it is easy to connect and deploy. Additional benefits include ongoing maintenance and an overall reduction of costs. To ensure security, the Aironet 1130AG uses the Cisco Wireless Security Suite, supporting 802.11i, Wi-Fi Protected Access (WPA), WPA2, and many types of EAP. In addition, the radio's power can be adjusted to fine-tune the device for operation in various environments. Cisco Aironet 1200 SeriesThe big brother to the Aironet 1100 is the Cisco Aironet 1200. The 1200 series (shown in Figure 1-5) incorporates single or dual radios, and it allows connectivity in both the 2.4-GHz (802.11g) or 5-GHz (802.11a) bands. The device can be configured for optimal flexibility (as shown in Figure 1-6), and it can be set up to operate solely in the 802.11a, 802.11b, or 802.11g mode. Alternately, it can be set in dual mode, which allows connectivity for clients operating in two different protocols. Ultimately, it can be set in trimode, to offer simultaneous service for all three protocols. This functionality provides great flexibility and return on investment because devices using any of the popular protocols can be used. Figure 1-5. Cisco Aironet 1200 AP
Figure 1-6. The Aironet 1200 Allows Connections in Single, Dual, or Trimode
Like the Aironet 1100 series, the Aironet 1200 offers up to 16 VLANs, QoS capabilities, and Cisco Wireless Security Suite manages its security set. The Aironet 1200 series is an important component in the Cisco Structured Wireless-Aware Network (SWAN). SWAN is a framework for deploying, operating, and managing thousands of Aironet APs when using a Cisco infrastructure. For 802.11a networks, the Aironet 1200 series offers a variety of antennas including one that can be configured omnidirectionally (in a circle surrounding the AP) or as a patch antenna that directs a hemispherical signal from the wall and across the room. Note Antennas are explained in greater detail in Chapter 2, "Cisco Antennas." Like the Aironet 1100 series, the Aironet 1200 Series is managed either via the command line using IOS or via a browser-based GUI. Aironet 1230AG Series APThe Aironet 1230AG Series AP provides many of the same features as its younger brother, the 1130AGchiefly dual 802.11a and 802.11g radios. However, the Aironet 1230AG is designed for environments in which omnidirectional antennas would be lacking. The 1130AG AP employs only internal antennas, but the 1230AG AP features connectors for external antennas. This is ideal in environments such as factories, warehouses, or large retail facilities that require specialized antennas for proper functionality. Figure 1-7 shows this device. Figure 1-7. Cisco Aironet 1230AG AP
Like other AP offerings from Cisco, the Aironet 1230AG AP is a component of the Cisco SWAN framework that delivers an integrated wired and wireless network. Because the device uses both 802.11a and 802.11g radios, up to 15 nonoverlapping channels are available. This number will increase to 22 channels in a future firmware release. The Aironet 1230AG AP is rugged enough to withstand high levels of heat. Cisco Aironet 1300 SeriesFor outdoor wireless applications, Cisco offers its Aironet 1300 Series of APs, shown in Figure 1-8. These APs are encased in a tough, durable exterior, which makes them well suited for operation in the elements. In addition to its work as an AP, this device is also used as a network bridge (which is explained in greater detail in the "Cisco Wireless Bridges" section). Figure 1-8. Cisco Aironet 1300 AP
Note Although the Aironet 1300 is designed for outdoor environments, it can still be used indoors. The Aironet 1300 supports the 802.11g standards, providing data transfer rates of up to 54 Mbps. These APs are not just for employees to take their laptops outside during lunch breaks. A number of organizations that benefit from an outdoor AP include the following:
The AP can manage 16 VLANs and 24 Voice over IP (VoIP) circuits on a point-to-point link. It also uses the Cisco Wireless Security Suite for its security chores. The Cisco Aironet 1300 can be easily managed as part of a Cisco SWAN solution (Chapter 3, "Cisco Wireless Technologies," covers SWAN in more detail). In addition, the command line or browser-based GUI can manage it. AP Quick ComparisonWhen considering which AP is best for your organization's needs, a number of variables come into play. Table 1-1 through Table 1-5 compare popular traits of these Cisco APs.
For more information on connecting your APs, flip ahead to Chapter 5. Note You might still see Cisco Aironet 350 APs in organizations that were early adopters of wireless networking technology. These devices operated using only the 802.11b protocol. Cisco has phased out this device and no longer supports it. However, because it employs the 802.11b protocol, it is still compatible with other 802.11g devices. The Aironet 350 bridge is still available. Bridge devices are discussed in the section, "Cisco Wireless Bridges." |