Руководство По Проектированию для Cisco Cisco Aironet 1522 Lightweight Outdoor Mesh Access Point

Скачать
Страница из 271
58
Cisco Mesh Access Points, Design and Deployment Guide, 7.2
OL-21848-03
  Architecture Overview
Figure 41
Wireless Mesh Frame
As this frame is sent, the transmitter and receiver addresses change on a hop-by-hop basis. AWPP is used 
to determine the receiver address at each hop. The transmitter address is known because it is the current 
mesh access point. The source and destination addresses are the same over the entire path.
If the RAP’s controller connection is Layer 3, the destination address for the frame is the default gateway 
MAC address, because the MAP has already encapsulated the CAPWAP in the IP packet to send it to the 
controller, and is using the standard IP behavior of using ARP to find the MAC address of the default 
gateway.
Each mesh access point within the mesh forms an CAPWAP session with a controller. WLAN traffic is 
encapsulated inside CAPWAP and is mapped to a VLAN interface on the controller. Bridged Ethernet 
traffic can be passed from each Ethernet interface on the mesh network and does not have to be mapped 
to an interface on the controller (see 
).
Figure 42
Logical Bridge and WLAN Mapping
Mesh Neighbors, Parents, and Children
Relationships among mesh access points are as a parent, child, or neighbor (see 
). 
A parent access point offers the best route back to the RAP based on its ease values. A parent can 
be either the RAP itself or another MAP. 
Ease is calculated using the SNR and link hop value of each neighbor. Given multiple choices, 
generally an access point with a higher ease value is selected.
A child access point selects the parent access point as its best route back to the RAP. 
A neighbor access point is within RF range of another access point but is not selected as its parent 
or a child because its ease values are lower than that of the parent.
Frame Control: 0x0308 (Normal)
Duration: 48
Receiver address: Airespac_53:03:40 (00:0b:85:53:03:40)
Transmitter address: Airspac_23:d5:60 (00:0b:85:23:d5:60)
Destination address: Airspac_40:23:a3 (00:0b:85:40:23:a3)
Fragment number: 0
Sequence number: 1410
Source address: Airspac_53:03:70 (00:0b:85:53:03:70)
148449
PAP:03:70
PAP:D5:60
PAP:03:40
Controller:23:a3
CAPWAP Tunnel
Bridged Ethernet
VLAN mapped to WLAN
WLANs
Bridged Ethernet
205684