IgniteNet SunSpot AC1200, Руководство пользователя

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Chapter 4
| Wireless Settings
VLAN Settings
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STBC — Space-time Block Coding sends multiple copies of the same data over
a number of antennas, using the various received versions to improve the
reliability of data transfer. The transmitted signal may traverse a difficult
environment with scattering, reflection, and refraction which may then be
further corrupted by thermal noise in the receiver, so some of the received
copies will be better than others. This redundancy results in a higher chance of
being able to use one or more of the received copies to correctly decode the
received signal. (Default: Disabled)
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AMPDU — Enables or disables the use of Aggregated MAC Protocol Data Units.
Physical layer (PHY) data rate improvements do not increase real throughput
beyond a point because of 802.11 protocol overheads. The main media access
control feature that provides a performance improvement is aggregation.
Aggregation of MAC protocol data units (MPDUs) is referred to as MPDU
aggregation or (A-MPDU). (Default: Enabled)
VLAN Settings
VLANs (virtual local area networks) are turned off by default. If turned on they will
automatically tag any packets passed to the LAN port from the relevant VAP (virtual
access point).
The access point can employ VLAN tagging to control access to network resources
and increase security. VLANs separate traffic passing between the access point,
associated clients, and the wired network. You can configure a VLAN for up to 13
VAP interfaces.
Note the following points about the access point’s VLAN support:
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If an Ethernet LAN port on the access point is assigned a VLAN ID, any traffic
entering that port must be also tagged with the same VLAN ID.
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A management VLAN can be used for managing the access point through
remote management tools, such as the web interface, SSH, Telnet or SNMP.
The access point can be configured to only accept management traffic that is
tagged with the specified management VLAN ID. This ID must be assigned to
the Ethernet ports or radio interfaces which are designated to handle
management traffic.
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Wireless clients associated to the access point can be assigned to a VLAN.
Wireless clients are assigned to the VLAN for the VAP interface with which they
are associated. The access point only allows traffic tagged with correct VLAN
IDs to be forwarded to associated clients on each VAP interface.
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When VLAN support is enabled on the access point, traffic passed to the wired
network is tagged with the appropriate VLAN ID. When an Ethernet port on the
access point is configured as a VLAN member, traffic received from the wired