Cisco Cisco Aironet 350 Wireless Bridge Guía Para Resolver Problemas
emerged specifically for wireless application. Refer to Cisco Wireless LAN Controller Command Reference,
Release 6.0 for more information.
Release 6.0 for more information.
Homogeneous Clients
In an environemnt where homogeneous clients are found to exist, data rates are higher than in a mixed
environment. For example, the presence of 802.11b clients in a 802.11g environment, 802.11g has to
implement a protection mechanism in order to co−exist with the 802.11b client, and therefore results in
decreased data rates.
environment. For example, the presence of 802.11b clients in a 802.11g environment, 802.11g has to
implement a protection mechanism in order to co−exist with the 802.11b client, and therefore results in
decreased data rates.
The Test Design
The following information is specifically related to the actual testing of the aggregation of three Cisco Aironet
350 Series bridges. The equipment used included six Cisco Aironet 350 bridges, two Cisco Catalyst® 3512
XL switches, and two Cisco 2621 routers. This design may also be used with two bridge pairs instead of three.
The test design used Enhanced IGRP as the routing protocol with equal−cost load balancing, and CEF as the
forwarding mechanism.
350 Series bridges. The equipment used included six Cisco Aironet 350 bridges, two Cisco Catalyst® 3512
XL switches, and two Cisco 2621 routers. This design may also be used with two bridge pairs instead of three.
The test design used Enhanced IGRP as the routing protocol with equal−cost load balancing, and CEF as the
forwarding mechanism.
Most likely you will be using some hardware other than the specific models tested. Here are some guidelines
when choosing the equipment to be used to aggregate bridges.
when choosing the equipment to be used to aggregate bridges.
Routers
The routers used for testing had two Fast Ethernet (100−Mbps) ports and supported 802.1q trunking and
CEF−based switching. It's possible to use a single 100−Mbps port to trunk all traffic to and from a switch.
However, the use of a single Fast Ethernet port was not tested and could interject unknown issues or
negatively impact performance. A router with four Fast Ethernet ports would not require the use of a VLAN
trunking protocol. Other router considerations include:
CEF−based switching. It's possible to use a single 100−Mbps port to trunk all traffic to and from a switch.
However, the use of a single Fast Ethernet port was not tested and could interject unknown issues or
negatively impact performance. A router with four Fast Ethernet ports would not require the use of a VLAN
trunking protocol. Other router considerations include:
For 802.1q trunking support, Cisco 2600 and 3600 Series routers require Cisco IOS® Software
Release 12.2(8)T or higher.
Release 12.2(8)T or higher.
•
If the routers don't support 802.1q trunking, check if they support ISL trunking, a Cisco proprietary
trunking mechanism that can be used in place of 802.1q. Before you configure the routers, verify that
your switch supports ISL trunking.
trunking mechanism that can be used in place of 802.1q. Before you configure the routers, verify that
your switch supports ISL trunking.
•
For Cisco 2600 and 3600 Series routers, IP Plus code is required for 802.1q trunk support (this would
be a cost upgrade from IP code).
be a cost upgrade from IP code).
•
Depending on the hardware and its intended use, the base flash and DRAM may need to be increased.
Take into consideration additional memory−intensive processes such as CEF tables, routing protocol
requirements, or other processes running on the router that are not specifically related to the bridge
aggregation configuration.
Take into consideration additional memory−intensive processes such as CEF tables, routing protocol
requirements, or other processes running on the router that are not specifically related to the bridge
aggregation configuration.
•
CPU utilization may be a consideration depending on the configuration and features used on the
router.
router.
•
Consult the Feature Navigator (registered customers only) for Cisco IOS Software support for IEEE 802.1q
VLAN trunking on your specific hardware platform.
VLAN trunking on your specific hardware platform.
Switches
The switches in the tested design require support for VLANs and 802.1q trunking. Using inline
power−enabled switches such as the Cisco Catalyst 3524PWR when using Cisco Aironet 350 Series bridges is
recommended, as this will make the setup less cumbersome. To collapse the switch and routing functionality
into a single box, the Catalyst 3550 was tested and works quite well.
power−enabled switches such as the Cisco Catalyst 3524PWR when using Cisco Aironet 350 Series bridges is
recommended, as this will make the setup less cumbersome. To collapse the switch and routing functionality
into a single box, the Catalyst 3550 was tested and works quite well.