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TANDBERG and Wireless LANs
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TANDBERG
D12809, Rev 1.0
This document is not to be reproduced in whole or in
part without the permission in writing from:
TANDBERG
TANDBERG
TANDBERG and Wireless LANs
1. Overview Of Wireless Standards
1.1 802.11 Wireless Ethernet
Ethernet was pioneered by Xerox in the 1970’s and was in fact a registered trademark of
Xerox Corporation. After further development, the technology was improved and became
known as Ethernet II. Xerox, with the help from Digital and Intel began establishing and
publishing the standards. Realizing the international community would not recognize the
standard, IEEE was charged with formalizing the standard along with other LAN
technologies. The 802 committee was assembled to investigate Ethernet, Token Ring, Fiber
Optic, and other LAN technology.
1.1.1 802.11a
The 802.11a specification applies to wireless ATM systems and is primarily used in access
hubs. This specification operates at 5GHz and 6GHz. By using a modulation scheme of
orthogonal frequency division multiplexing (OFDM), 802.11a can achieve speeds up to
54Mbps. However, speeds of 6Mbps, 12Mbps and 24Mbps are more common.
1.1.2 802.11b
The 802.11b specification, also known as Wi-Fi, uses complementary code keying (CCK)
phase-shift keying (PSK) instead of the traditional phase-shift keying (PSK) used in 802.11.
The use of CCK allows for higher data speeds and less interference to multipath-propagation
interference. 802.11b operates at 2.4GHz and allows for speeds up to 11Mbps.
1.1.3 802.11g
The 802.11g specification allows for speeds up to 54Mbps over short distances. The
802.11g standard also operates at 2.4GHz and is compatible with 802.11b.
1.2 BlueTooth
BlueTooth is another wireless standard named for the 10th Century Viking king Harald
Blåtand of Denmark. The Bluetooth wireless specification defines a low-power, low-cost
technology that provides a standardized platform for eliminating cables between mobile
devices and facilitating connections between products. Bluetooth operates at the unlicensed
2.4GHz frequency. The standard uses a spread spectrum, frequency hopping, full-duplex
signal at up to 1600 hops/sec. The signal hops among 79 frequencies at 1 MHz intervals to
give a high degree of interference immunity.
TANDBERG
TANDBERG and Wireless LANs
2. TANDBERG’s Implementation
TANDBERG has implemented the 802.11b standard into the
TANDBERG 1000 product, using a standard PC card, to deliver
768kbps of exceptional video and audio quality. This feature allows
for ‘hot desk’ applications where a video conferencing unit may be
shared from desk to desk without the need for expensive Ethernet
cabling.
2.1 Supported PC Cards
TANDBERG continues to develop drivers for different wireless cards
based upon market requests and availability of the PC cards. Currently, TANDBERG
supports the following PC cards for 802.11b based on their global availability and popularity
among the wireless community. While it is possible through the 802.11b standard to mix
wireless network interface cards (NIC) and access point vendors, TANDBERG
recommends using the same vendor for both to minimize any possible interoperability
problems.
B3.3 (and later)
B4 (and later)
v
v
v
v
v
v
v
Compaq WL110
Lucent Orinoco Silver
Lucent Orinoco Gold
Cisco Aironet 350
2.2 Features and Menu Settings
The following features are available through the user interface for set up.
2.2.1 SSID (Service Set Identification)
Requirement: Mandatory
The SSID, also known as ESSID (extended SSID), is the network name or network ID on
which the particular unit will operate. This is very similar in comparison to a NT domain and
can be comprised of text and/or numbers. It is important to use the same SSID as the
access point. If the SSID in the TANDBERG unit is incorrect (this includes case sensitive
mistakes) the unit will not be able to communicate with the access point. The SSID is a case
sensitive label.
2.2.2 Community
Requirement: Optional
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TANDBERG and Wireless LANs
The Community name, also known as Nickname, can be used to attach a TANDBERG unit
to a specific access point when all access points share the same SSID. The feature is not
required to function properly.
TANDBERG
TANDBERG and Wireless LANs
2.2.3 Mode
Requirement: Mandatory
The mode setting allows for two different modes of operation.
Also known as peer to peer and IBSS Ad Hoc. This mode is used when
Adhoc:
communication is required between two units and an access point is not available.
Additionally , if there is no need to communicate with a wired unit on a standard LAN, you
can use this option. This is similar to a ‘back to back’ Ethernet cable used to connect two IP
enabled devices without a LAN.
Also known as Infrastructure, Base Station, or Access Point. When using an
Managed:
access point to connect a wired LAN to a wireless LAN. This is the most popular
application. If this mode is used, the SSID in the TANDBERG unit must match the SSID in
the access point.
2.2.4 Security – Encryption
The TANDBERG wireless 802.11b feature also supports Wired Equivalent Privacy (WEP)
with the choice of 64-bit, 128-bit, or no encryption. This feature allows the wireless network
to prevent an unauthorized person from using the network resources. It is important to
remember that the encryption keys in the access point and in the TANDBERG unit must
match. If the encryption keys do not match, and the SSID is correct, you will get an IP
address but will not be able to transmit video and audio.
The encryption keys can be entered as a hexadecimal or as ASCII using a ‘*’ prefix.
Example:
Deffe57563dee
*secretkey
hexadecimal
ASCII
The 64-bit key can be 10 hexadecimals or ‘*’ + 5 ASCII characters. The 128-bit keys can
be 26 hexadecimals or ‘*’ + 13 ASCII characters.
Additional security is offered in some access points by requiring the MAC addresses of the
802.11b NIC cards to be registered in the access point. Only units with the MAC
addresses can use the access point.
3. Applications
3.1 Why Wireless?
The IP network is becoming a viable network for video conferencing. Now that more
companies are beginning to switch to IP for their video conferencing needs, alternate
methods of transmission are becoming necessary. The use of wireless 802.11b is allowing
TANDBERG
TANDBERG and Wireless LANs
the rollout of videoconferencing to be seamless and quick. Wireless LANs offer the
following productivity, convenience, and cost advantages over traditional wired networks:
: Wireless LAN systems can provide video users with the ability to make
Mobility
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video calls anywhere in their organization regardless if they have an Ethernet
connection in the room. This mobility supports productivity and service opportunities
not possible with wired networks.
: Installing a wireless LAN system can be fast
Installation Speed and Simplicity
and easy and can eliminate the need to pull cable through walls and ceilings. This is
the concept behind ‘hot desking’.
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: Wireless technology allows the network to go where wire
Installation Flexibility
cannot go and allows the user to be more creative in deploying their video
conferencing needs.
: While the initial investment required for wireless
Reduced Cost-of-Ownership
LAN hardware can be higher than the cost of wired LAN hardware, overall
installation expenses and life-cycle costs can be significantly lower. Long-term cost
benefits are greatest in dynamic environments requiring frequent moves and changes.
: Wireless LAN systems can be configured in a variety of topologies to
Scalability
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meet the needs of specific applications and installations. Configurations are easily
changed and range from peer-to-peer networks suitable for a small number of users
to full infrastructure networks of thousands of users that enable roaming over a broad
area.
How Wireless LANs Are Used in the Real World
Wireless LANs frequently augment rather than replace wired LAN networks—often
providing the final few meters of connectivity between a wired network and the mobile user.
The following list describes some of the many applications made possible through the power
and flexibility of wireless LANs:
Doctors and nurses can use video in any room and not be limited to only using the
room with the system.
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Network managers in dynamic environments minimize the overhead caused by
moves, extensions to networks, and other changes with wireless LANs.
Training sites at corporations and students at universities use wireless connectivity to
minimize the cables to the desktop
Network managers installing networked computers in older buildings find that
wireless LANs are a cost-effective network infrastructure solution.
Trade show and branch office workers minimize setup requirements by installing pre-
configured wireless LANs needing no local MIS support.
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TANDBERG and Wireless LANs
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Network managers implement wireless LANs to provide backup for mission-critical
applications running on wired networks.
4. Glossary
Adhoc – A mode used to allow two 802.11b units to communicate without the use of an
access point.
ESSID – Extended SSID. See SSID.
Infrastructure – See Managed
Managed – A mode used to communicate to a 802.11b access point. This mode is
necessary to communicate to a wire LAN through an access point.
NIC – Network Interface Card.
Peer to Peer – See Adhoc
SSID – Service Set Identifier. This defines a local network ID similar to a NT domain
WEP – Wired Equivalency Privacy. This is an encryption standard that allows for security
across 802.11b networks between the NIC and the access point.
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