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•

Choose placement carefully.

For best results, place your router:

–

Near the center of the area in which your computers will operate.

–

In an elevated location such as a high shelf where the wirelessly connected computers

have line-of-sight access (even if through walls).

–

Avoid obstacles to wireless signals.

–

Keep wireless devices at least 2 feet from large metal fixtures such as file cabinets,

refrigerators, pipes, metal ceilings, reinforced concrete, and metal partitions.

–

Keep away from large amounts of water such as fish tanks and water coolers.

•

Reduce interference.

–

Avoid windows unless communicating between buildings.

–

Place wireless devices away from various electromagnetic noise sources, especially those

in the 2400–2500 MHz frequency band. Common noise-creating sources are:

•

Computers and fax machines (no closer than 1 foot)

•

Copying machines, elevators, and cell phones (no closer than 6 feet)

•

Microwave ovens (no closer than 10 feet)

•

Choose your settings.

–

Use a scanning utility to determine what other wireless networks are operating nearby, and

choose an unused channel.

–

Turn off SSID broadcast, and change the default SSID. Other nearby devices might

automatically try to connect to your network several times a second, which can cause

significant performance reduction.

•

Use WMM to improve the performance of voice and video traffic over the wireless link.

Using WMM for Wireless Multimedia Applications

The Wireless-G Router supports Wi-Fi Multimedia (WMM) to prioritize wireless voice and video

traffic over the wireless link. WMM provides prioritization of wireless data packets from different

applications based on four access categories: voice, video, best effort, and background. For an

application to receive the benefits of WMM, both it and the client running that application must be

WMM enabled. Legacy applications that do not support WMM, and applications that do not

require, are assigned to the best effort category, which receives a lower priority than voice and

video. WMM QoS is enabled by default.

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Changing the MTU Size

The Maximum Transmission Unit (MTU) is the largest data packet a network device transmits.

When one network device communicates across the Internet with another, the data packets travel

through many devices along the way. If any device in the data path has a lower MTU setting than

the other devices, the data packets must be split or “fragmented” to accommodate the one with the

smallest MTU.

The best MTU setting for NETGEAR equipment is often just the default value, and changing the

value might fix one problem but cause another. Leave MTU unchanged unless one of these

situations occurs:

•

You have problems connecting to your ISP, or other Internet service, and either the technical

support of the ISP or of NETGEAR recommends changing the MTU size. These might require

an MTU change:

–

A secure Web site that will not open, or displays only part of a Web page

–

Yahoo e-mail

–

MSN

–

America Online’s DSL service

•

You use VPN and have severe performance problems.

•

You used a program to optimize MTU for performance reasons, and now you have

connectivity or performance problems.

Note:

An incorrect MTU setting can cause Internet communication problems such as the

inability to access certain Web sites, frames within Web sites, secure login pages,

or FTP or POP servers.

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If you suspect an MTU problem, a common solution is to change the MTU size to 1400. If you are

willing to experiment, you can gradually reduce the MTU size from the maximum value of 1500

until the problem goes away.

Table 5-1

describes common MTU sizes and applications.

To change the MTU size:

1.

In the main menu, under Advanced, select

WAN Setup

.

2.

In the

MTU Size

field, enter a new size between 64 and 1500.

3.

Click

Apply

to save the new configuration.

Overview of Home and Small Office Networking

Technologies

Common connection types and their speed and security considerations are:

•

Broadband Internet

.

Your Internet connection speed is determined by your modem type,

such as ADSL or cable modem, as well as the connection speed of the sites to which you

connect, and general Internet traffic. ADSL and cable modem connections are asymmetrical,

meaning they have a lower data rate

to

the Internet (upstream) than

from

the Internet

(downstream). Keep in mind that when you connect to another site that also has an

asymmetrical connection, the data rate between your sites is limited by each side’s upstream

data rate. A typical residential ADSL or cable modem connection provides a downstream

throughput of about 1 to 3 megabits per second (Mbps). Newer technologies such as ADSL2+

and Fiber to the Home (FTTH) will increase the connection speed to tens of Mbps.

Table 5-1.

Common MTU Sizes

MTU

Application

1500

The largest Ethernet packet size and the default value. This is the typical setting for non-

PPPoE, non-VPN connections, and is the default value for NETGEAR routers, adapters,

and switches.

1492

Used in PPPoE environments.

1472

Maximum size to use for pinging. (Larger packets are fragmented.)

1468

Used in some DHCP environments.

1460

Usable by AOL if you do not have large e-mail attachments, for example.

1436

Used in PPTP environments or with VPN.

1400

Maximum size for AOL DSL.

576

Typical value to connect to dial-up ISPs.

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•

Wireless

.

Your Wireless-G Router Model WGR614v9 provides a wireless data throughput of

up to 300 Mbps using technology called multiple input, multiple output (MIMO), in which

multiple antennas transmit multiple streams of data. The use of multiple antennas also

provides excellent range and coverage. With the introduction of the newer WPA and WPA2

encryption and authentication protocols, wireless security is extremely strong.

To get the best performance, use RangeMax NEXT adapters such as the WN511B for your

computers. Although the RangeMax NEXT router is compatible with older 802.11b and

802.11g adapters, the use of these older wireless technologies in your network can result in

lower throughput overall (typically less than 10 Mbps for 802.11b and less than 40 Mbps for

802.11g). In addition, many older wireless products do not support the latest security

protocols, WPA and WPA2.

•

Powerline

.

For connecting rooms or floors that are blocked by obstructions or are distant

vertically, consider networking over your building’s AC wiring. NETGEAR’s Powerline HD

family of products delivers up to 200 Mbps to any outlet, while the older-generation XE

family of products delivers 14 Mbps or 85 Mbps. Data transmissions are encrypted for

security, and you can configure an individual network password to prevent neighbors from

connecting.

The Powerline HD family of products can coexist on the same network with older-generation

XE family products or HomePlug 1.0 products, but they are not interoperable with these older

products.

•

Wired Ethernet

.

As gigabit-speed Ethernet ports (10/100/1000 Mbps) become common on

newer computers, wired Ethernet remains a good choice for speed, economy, and security.

Gigabit Ethernet can extend up to 100 meters with twisted-pair wiring of Cat 5e or better. A

wired connection is not susceptible to interference, and eavesdropping would require a

physical connection to your network.

Assessing Your Speed Requirements

Because your Internet connection is likely to operate at a much lower speed than your local

network, faster local networking technologies might not improve your Internet experience.

However, many emerging home applications require high data rates. For example:

•

Streaming HD video requires 10 to 30 Mbps per stream. Because latency and packet loss can

disrupt your video, plan to provide at least twice the capacity you need.

Note:

Actual data throughput will vary. Network conditions and environmental factors,

including volume of network traffic, building materials and construction, and

network overhead, can lower actual data throughput rate.

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•

Streaming MP3 audio requires less than 1 Mbps per stream and does not strain most modern

networks. Like video, however, streaming audio is also sensitive to latency and packet loss, so

a congested network or a noisy link can cause problems.

•

Backing up computers over the network has become popular due to the availability of

inexpensive mass storage.

Table 5-2

shows the time to transfer 1 gigabyte (1 GB) of data using

various networking technologies.

Table 5-2.

Theoretical Transfer Time for 1 Gigabyte

Network Connection

Theoretical Raw Transfer Time

Gigabit wired Ethernet

8 seconds

RangeMax NEXT Wireless-N

26 seconds

Powerline HD

40 seconds

100 Mbps wired Ethernet

80 seconds

802.11n wireless

45 seconds

802.11g wireless

150 seconds

802.11b wireless

700 seconds

10 Mbps wired Ethernet

800 seconds

Cable modem (3 Mbps)

2700 seconds

Analog modem (56 kbps)

144,000 seconds (40 hours)