Deploying a Fast and Stable Wireless Mesh Network
- Mesh Code Releases
- Mesh Deployments
- How Mesh Works
- Ethernet Bridging
- Troubleshooting Mesh
- Summary
This chapter is from the book
This chapter is from the book
This chapter is from the book
The wireless mesh deployment access points (AP), along with the wireless controllers, allow you to provide a secure wireless solution for outdoor environments such as a college campus or an entire city. The mesh feature allows you to place APs in areas where you have no wired Ethernet network connection. A mesh deployment consists of a root AP (RAP) and one or more mesh APs (MAP). The RAP provides the wired link back to the controller for the MAPs. In order to avoid confusion throughout the rest of the chapter, when referring to the mesh series of APs, they will be called 'mesh APs', whereas the term 'MAP' will refer to a mesh AP that is connected to the controller wirelessly through a RAP.
Originally, only the 1500 and 1520 series APs, outdoor mesh APs, supported mesh deployments. In later code releases, however, Cisco introduced Enterprise Mesh, indoor mesh APs, which allows you to use 1130 and 1240 series APs to install a mesh wireless network indoors.
MAPs use their 802.11a radios as a wireless backhaul to join the controller and send client traffic to the wired network through the RAP. The wireless clients in a mesh network associate to the mesh AP's 802.11b/radio.
Currently, you can find four different models of outdoor mesh APs in the field:
- 1505
- 1510
- 1522
- 1524
The 1505 model is a 802.11b/g only radio, so client access and the backhaul use the single radio. The 1510 model has both an 802.11a and 802.11b/g radio, which allows the AP to have a dedicated radio for the backhaul and a dedicated radio for client access. The 1505 and 1510 series APs are difficult to troubleshoot because they do not have LEDs or standard console cable access. Therefore, without taking the units down and connecting them in a lab environment, it would be nearly impossible to determine if the APs were actually powered up and working. The 1500 series models are end of sale and no longer available for purchase. In November 2013, Cisco will no longer support the 1500 series APs.
The 152x series APs are a dramatic improvement over the 1500s. They have LEDs and standard console connections. You can even enable remote Telnet on the APs and run debug and show commands directly on the APs to help with problem analysis.
Mesh Code Releases
Before the 4.2 release of code, mesh features were included in the main code base for all controllers. Mesh development, bug fixes, and features, however, were being delayed because of mainline code release timelines. To facilitate the development of mesh and get bug fixes to customers faster, Cisco split mesh into its own code branch. The original mesh-only branch uses the 4.1 code base and retains the 4.1 naming convention with an M at the end. An example is 4.1.192.22M.
Although splitting the mesh and mainline code into two separate code bases allowed Cisco to release mesh enhancements and bug fixes faster, it introduced two limitations:
-
With the early mesh releases, only the 1500 and 1520 series APs were supported.
This meant that if you had other APs models, you had to have two controllers: one for mesh and one for the indoor APs. With mesh Release 4.1.191.24M, Cisco added support for the 1000, 1100, 1200, 1230, 1130, 1240, and 1300 series APs.
- Because the base code is 4.1, 1250, 1140, and 801 series APs are not supported.
Starting with the 5.2 release of code, Cisco merged the mesh-only and mainline code releases. The 1500 series APs are not supported on 5.2 code. To address security vulnerabilities inherent in the 4.1 code base for customers who have deployed 1500 series APs, Cisco released 4.2.176.51M code in June 2009.