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Q1:How
to Enable WPA function for Wireless-B/G products? |
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A:For
your information Here |
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Q2:What
is wireless networking? |
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A:The
term wireless networking refers to technology that enables two or
more computers to communicate using standard network protocols, but
without network cabling. Strictly speaking, any technology that does
this could be called wireless networking. The current buzzword however
generally refers to wireless LANs. This technology, fuelled by the
emergence of cross-vendor industry standards such as IEEE 802.11,
has produced a number of affordable wireless solutions that are growing
in popularity with business and schools as well as sophisticated applications
where network wiring is impossible, such as in warehousing or point-of-sale
handheld equipment. |
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Q3:What
is a wireless network made up of? |
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A:There
are two kinds of wireless networks:
a. An ad-hoc, or peer-to-peer wireless network consists of a number
of computers each equipped with a wireless networking interface card.
Each computer can communicate directly with all of the other wireless
enabled computers. They can share files and printers this way, but
may not be able to access wired LAN resources, unless one of the computers
acts as a bridge to the wired LAN using special software. (This is
called "bridging")
Figure 1: Ad-Hoc or Peer-to Peer Networking.
Each computer with a wireless interface can communicate directly with
all of the others.
b. A wireless
network can also use an access point, or base station. In this type
of network the access point acts like a hub, providing connectivity
for the wireless computers. It can connect (or "bridge")
the wireless LAN to a wired LAN, allowing wireless computer access
to LAN resources, such as file servers or existing Internet Connectivity.
There are two types of access points:
i. Dedicated hardware access points (HAP) such as Lucent's WaveLAN,
Apple's Airport Base Station or WebGear's AviatorPRO. (See
Figure 2). Hardware access points offer comprehensive support
of most wireless features, but check your requirements carefully.
ii. Software Access Points which run on a computer equipped with a
wireless network interface card as used in an ad-hoc or peer-to-peer
wireless network. (See Figure 3) The
Vicomsoft InterGate suites are software routers that can be used as
a basic Software Access Point, and include features not commonly found
in hardware solutions, such as Direct PPPoE support and extensive
configuration flexibility, but may not offer the full range of wireless
features defined in the 802.11 standard.
With appropriate networking software support, users on the wireless
LAN can share files and printers located on the wired LAN and vice
versa. Vicomsoft's solutions support file sharing using TCP/IP.
Figure 2: Hardware Access Point.
Wireless connected computers using a Hardware Access Point.
Figure
3: Software Access Point.
Wireless connected computers using a Software Access Point.
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Q4:Can
I mix wireless equipment from different vendors? |
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A:Because
most wireless networking hardware vendors support the 802.11 standard
they can inter operate. However, we recommend verification as the
standard is a fairly recent one, and does specify two different methods
for wireless communications; Frequency Hopping (FH) and Direct Sequence
Spread Spectrum (DSSS or DS), which are not interoperable.
When purchasing wireless networking hardware from separate vendors
be sure to obtain guarantees from the vendors that the hardware will
interoperate and follows the standards.
Within a short time we expect all new wireless cards, like Ethernet
cards, to become inexpensive, ubiquitous and totally interoperable.
Also of note is that the latest version of the standard defines 11mbps
and 5.5mbps networking, with support for the older standard 1mbps
and 2mbps speeds. This provides some compatibility with different
or older equipment. Note that this new standard covers DS-type Networks,
not FH types.
Software access points such as InterGate which uses the wireless interface
of the host computer should have no compatibility issues with third
party wireless hardware, as long as standards are followed. Typically
wireless hardware is identified to the software as a network interface,
and therefore can be used in the same way as any other network card.
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Q5:If
my computer is connected to a wireless LAN, can it communicate with
computers on a wired LAN as well? |
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A:To
do this you will need some sort of bridge between the wireless and
wired network. This can be accomplished either with a hardware access
point or a software access point. Hardware access points are available
with various types of network interfaces, such as Ethernet or Token
Ring, but typically require extra hardware to be purchased if your
networking requirements change.
If networking requirements go beyond just interconnecting a wired
network network to a small wireless network, a software access point
may be the best solution.
A software access point does not limit the type or number of network
interfaces you use. It may also allow considerable flexibility in
providing access to different network types, such as different types
of Ethernet, Wireless and Token Ring networks. Such connections are
only limited by the number of slots or interfaces in the computer
used for this task.
Further to this the software access point may include significant
additional features such as shared Internet access, web caching or
content filtering, providing significant benefits to users and administrators.
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Q6:What
is the range of a wireless network? |
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A:Each
access point has a finite range within which a wireless connection
can be maintained between the client computer and the access point.
The actual distance varies depending upon the environment; manufacturers
typically state both indoor and outdoor ranges to give a reasonable
indication of reliable performance. Also it should be noted that when
operating at the limits of range the performance may drop, as the
quality of connection deteriorates and the system compensates.
Typical indoor ranges are 150-300 feet, but can be shorter if the
building construction interferes with radio transmissions. Longer
ranges are possible, but performance will degrade with distance.
Outdoor ranges are quoted up to 1000 feet, but again this depends
upon the environment. |
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Q7:How
many wireless networked computers can use a single access point? |
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A:This
depends upon the manufacturer. Some hardware access points have a
recommended limit of 10, with other more expensive access points supporting
up to 100 wireless connections. Using more computers than recommended
will cause performance and reliability to suffer.
Software access points may also impose user limitations, but this
depends upon the specific software, and the host computer's ability
to process the required information. |
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Q8:Can
I have more than one access point? |
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A:Yes,
multiple access points can be connected to a wired LAN, or sometimes
even to a second wireless LAN if the access point supports this.
In most cases, separate access points are interconnected via a wired
LAN, providing wireless connectivity in specific areas such as offices
or classrooms, but connected to a main wired LAN for access to network
resources, such as file servers. (See Figure
4)
Figure 4: Multiple Access Points.
Wireless connected computers using Multiple Access Points.
If a single area is too large to be covered by a single access point,
then multiple access points or extension points can be used. -- Note
that an "extension point" is not defined in the wireless
standard, but have been developed by some manufacturers. When using
multiple access points, each access point wireless area should overlap
its neighbors. This provides a seamless area for users to move around
in using a feature called "roaming. " (See the next question
for an explanation of Roaming)
Some manufacturers produce extension points, which act as wireless
relays, extending the range of a single access point. Multiple extension
points can be strung together to provide wireless access to far away
locations from the central access point. (See
Figure 5)
Figure 5: Extension Point.
Wireless connected computers using an Access Point with an Extension
Point.
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Q9:What
is Roaming? |
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A:A
wireless computer can "roam" from one access point to another,
with the software and hardware maintaining a steady network connection
by monitoring the signal strength from in-range access points and
locking on to the one with the best quality. Usually this is completely
transparent to the user; they are not aware that a different access
point is being used from area to area. Some access point configurations
require security authentication when swapping access points, usually
in the form of a password dialog box.
Access points are required to have overlapping wireless areas to achieve
this as can be seen in the following diagram:
Figure 6: Roaming.
A user can move from Area 1 to Area 2 transparently. The Wireless
networking hardware automatically swaps to the Access Point with the
best signal.
Not all access points are capable of being configured to support roaming.
Also of note is that any access points for a single vendor should
be used when implementing roaming, as there is no official standard
for this feature. |
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Q10:What
about security? |
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A:Wireless
communications obviously provide potential security issues, as an
intruder does not need physical access to the traditional wired network
in order to gain access to data communications. However, 802.11 wireless
communications cannot be received --much less decoded-- by simple
scanners, short wave receivers etc. This has led to the common misconception
that wireless communications cannot be eavesdropped at all. However,
eavesdropping is possible using specialist equipment.
To protect against any potential security issues, 802.11 wireless
communications have a function called WEP (Wired Equivalent Privacy),
a form of encryption which provides privacy comparable to that of
a traditional wired network. If the wireless network has information
that should be secure then WEP should be used, ensuring the data is
protected at traditional wired network levels.
Also it should be noted that traditional Virtual Private Networking
(VPN) techniques will work over wireless networks in the same way
as traditional wired networks.
Section Two - Wireless Networking and the Internet |
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Q11:How
can I use a wireless network to share an Internet connection? |
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A:Once
you realise that wireless cards are analogous to ethernet cards and
that empty space is analogous to ethernet cabling, the answer to this
question becomes clear. To share an Internet connection across a LAN
you need two things:
¥Ò¡B an Internet sharing hardware device or software program
¤A¡B a LAN
If your LAN is wireless, the same criteria apply. You need a hardware
or software access point and a wireless LAN. Any computer equipped
with a wireless network card running suitable Internet
sharing software can be used as a software access point. (See
Figure 8) A number of vendors offer hardware access points.
A hardware access point may provide Internet Sharing capabilities
to Wired LAN computers, but does not usually provide much flexibility
beyond very simple configurations. (See Figure
9)
Figure 8: Software Access Point.
Wireless connected computers using a Software Access Point for shared
Internet access.
Figure 9: Hardware Access Point.
Wireless connected computers using a Hardware Access Point for shared
Internet access.
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Q12:If
I have more than one hardware access point, how can I share a single
Internet connection? |
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A:If
an existing wired LAN already has an Internet connection, then the
hardware access points simply connect to your LAN and allow wireless
computers to access the existing Internet connection in the same way
as wired LAN computers.
Figure 10: Multiple Access Points.
Wireless connected computers using Multiple Access Points.
If there is no existing Internet connection, then this depends on
the access point:
Figure 11: Software Access Point sharing one Internet connection.
Wireless connected computers using Multiple Access Points. All wired
and wireless computers access the Internet through a single software
access point.
If an access point provides some form of Internet sharing itself,
then having multiple such access points connected to a wired LAN may
require some special configuration, or possibly may require an additional
Internet sharing device or software program. |
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Q13:If
I use a wireless network to connect to the Internet does my ISP need
a wireless network too? |
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A:If
you use a wireless network to connect to the Internet, the wireless
part only concerns your LAN. The communications link from your LAN
to your Internet service provider (ISP) would be identical whether
or not you had a wireless network. For example, if you connected an
Ethernet network to the Internet via a 56K modem, when you upgraded
your network to use wireless, you would still use the same 56K modem
to connect to the Internet. |
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Q14:How
to set up WDS (Wireless Distribution System) for WR-854? |
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A: |
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1.
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Click
Wireless tab to configure it, the ESSID value can be different from
others but all of Routers have the same channel on CWR-854. |
2.
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Enable
"Distribution System" and type MAC address of Router 1 of
CWR-854 on the "Peer AP MAC Address 1" field, and then click
on "apply" button. |
Router 1

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3.
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Enable
"Distribution System" and type MAC address of Router 2 of
CWR-854 on the "Peer AP MAC Address 1" field, and then click
on "apply" button. |
Router 2

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| 4. |
You must disable DHCP function for Router 2 then click on "apply"
button. |
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WDS
setting is completed now |
Router 2
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