A variety of help start using wireless Linux tools and projects
Level: primary
Roman VICHR
Roman@rdmax.com)
Subject expert
With the popularity of Wi-Fi, Linux has also joined this ranks. In this article, Roman Vichr illustrates how Linux provides help for many wireless tools and projects - simultaneously gets help.
Linux, Linux, Linux - This universal, stable, scalable, variable, and competitive platform has been wired. From desktops and servers that support wireless access to wireless access systems, it is becoming almost all of all common tools, and has already occupied a place in a wireless solution. In-depth understanding of Linux promotes how to promote wireless network.
Linux wireless access point: Build or purchase?
The basic problem is whether the Linux system has the ability to combine with other access points in the wireless network to provide a connection for fixed nodes and roaming wireless clients?
The actual installation of wireless LAN is not so important; the key depends on what you purchased, and it is supported under Linux system. Check and make sure you have hardware for a specific operating system driver. Keep in keeping, if you want to get high performance (that is, gigabit's data transfer speed), then choose wireless to you; even the latest standard, the transfer speed is less than 100 Mbps . Roaming Another challenge: maintains the connection between different access points. To help achieve this, set a Wired Equivalent Privacy, WEP button to detect access points you can connect. Remember, in practice, the main purpose of the access point is to be a bridge; that is, it should put the packet from a network route to another network.
This article focuses on various options and tools for managing these access points. Basically, you have to choose whether to use a wireless extensions. (Wireless extension is a name of a normal API, which allows the driver to inform users about the space structure and statistics details of common wireless LANs.) To get a detailed steps for installing access point software under Linux, please read articles
Build a wireless access point on Linux. To have a full overview of the bridge between the wireless network structure and the LAN and WLAN, please read Linux Wireless Access Point Howto (see Resources for more information).
Wireless signal strength
If you want to be a user who knows how to see, then you should know how to estimate the intensity of the wireless signal. Here is a simplified formula that reflects the wireless frequency signal loss of the 2.45 GHz frequency band used by the 802.11b / g of access point:
Signalloss = 40 20 * log (d);
Here, Signalloss is in units of DB, D is a distance from the meter. This is a simplified formula because it does not consider the signal loss caused by the wall material; despite this, it can still have a basic understanding of the wireless signal coverage.
Do not use wireless expansion
There are some technologies that don't use wireless extensions to help you create Linux wireless networks, including Linux-Irda and Bluez, the latter is Linux Bluetooth stack. in
Detailed description of the two in Linux wireless network technology. Another option is Rose (Refer to the reference information to get more information), this is a platform for building an 802.11 wireless access point. The advantage of ROSE is that it can be compiled for any platform (such as MIPS, X86, ARM, PowerPC). The supported WLAN card is based on INTERSIL PRISM CHIPSET 2 / 2.5 / 3. It also provides support for 5 GHz frequencies. The following is an additional ROSE feature: - Access point development kit.
- 802.11 Agreement and safety, MAC address filtering, IPv4 routing, firewall, Radius, QoS, Bridge, NAT, DHCP. Additional drivers such as 802.11a / g / h are also supported.
- For good support and maintainability, the Rose compiler is written with Python (with the available C compiler Gzip, with the Python language version 2.x - 2.x-2.1 and 2.2 of the standard Python library have been tested).
Basically, you can build a Linux-based wireless access point using ROSE (and Linux 2.4 core) and WLAN card based on 802.11 Intersil Prism.
Select wireless extension
The advantage of wireless extension is that a single set of tools can support all kinds of wireless LANs, regardless of their type (as long as the hardware driver supports wireless expansion). Another advantage is that these parameters do not need to restart the driver (or Linux) to modify during use.
A set of Linux tools for operating wireless extensions is often referred to as wireless tools. They use the text interface and are very simple. The main use in Linux implementation:
- IWCONFIG: Operate basic wireless parameters.
- IWLIST: Initialization Scan Frequency, list frequency, bit rate, and key.
- IWSPY: Gets the connection quality of each node.
- IWPRIV: Allows operations for wireless extensions specific to the Wi-Fi driver.
- IFRENAME: Allows the use of a fixed-standard name interface.
Friendly tool
Now come to see some tools, they provide a more friendly user front end for additional management tools for managing Wi-Fi. You will find links to all of these tools in the reference part.
Ifplugd / waproamd
WAPROAMD is a roaming daem that supports Linux wireless extensions (V15 or update versions), which has been tested on debian Linux. Its use is to configure the WEP key based on the network found. The WAProAMD tool scans repeatedly for wireless networks. When the NIC is associated with a available network, WaproAMD will no longer scan, but connect the NIC card to the discovered access point. Scan can be tested through the IWList scan command. If the Host AP driver is defined, WaproAMD supports host_roaming. Don't forget to install a firewall when using WAProAMD; the tool itself cannot prevent invasion.
KWIFIMANAGER
KwifiManager is a tool for configuring and monitoring your wireless LAN PC card in a kde environment on Linux; the tool itself is written for the 3.x version of KDE. It uses Linux kernel wireless extensions, so most of the wireless card has been supported by the PCMCIA-CS package. However, if your card uses drivers from the WLAN-NG project, there may be problems because these drivers are not 100% compatible with wireless extensions. Anyway, you can try it, or you can use the Host AP driver for the same block, which is compatible with wireless extensions. KwifiManager is issued in the form of an RPM package; however, there are some prerequisites for installation. These prerequisites are Qt toolkit (version 3.0.3 or more), KDE 3.x and GlibC2.2. These packages have the standard ./configure make make install compile and install this tool after the standard. - CONFIGURE Make Make Install. This app provides some display interfaces: Signal Quality, Connection Speed, Current Configuration, Access Point Monitor, Statistics Viewer, and Configuration Editor (the last display interface can be accessed).
GLINK is a link monitor and configurator for 802.11b card (this card using wireless extended Linux kernel), which is generally equivalent to the KwifiManager tool in GNOME.
APHUNTER
Aphunter is written with Perl and can give an Output of an IWLIST scan in a text file. You can call the documentation of this tool using the Perldoc -t. / APHUNTER command. This tool provides some switches to control their output and indicators.
Gkrelmwireless
This tool requires a wireless extended Linux kernel. This tool requires a C library to compile, of course, is installed using (g) make. (In BSD, in order to install you, you will need to add additional header files: if_wavelan_ieee.h and if_aironet_ieee.h.) This tool displays wireless link quality, link level, and noise. Its latest version can display level and noise in dbm in linux.
Collaborative work ability
When deploying wireless on the Linux platform, the collaborative work capability between different cards using the Linux driver is an important thing to consider. You should also ensure that different hardware parts themselves have a collaborative work ability; they should all understand the signals of each other in the same spectrum. Don't forget, it looks like a product, it may not have a collaborative work ability. For example, 802.11 and 802.11-FH products cannot work with 802.11-DS products, and vice versa.
chipset
Considering that some products may be supported while other products of the same brand may not be supported, the use of multiple chipsets in different wireless products may be a challenge. Sometimes, even if the same model number can be used, it may be different chipsets, which leads to difficult to determine if a card can be supported by Linux. However, most of the 802.11b cards used are all INTERSIL PRISMII chipsets, and this chipset has been well supported by Linux.
The 802.11b specification is only an extension of 802.11-DS, which increases the speed, but in any case, both products can be collaboratively working at at least 2 MBs (802.11-DS mode). The 802.11g standard is 802.11b non-direct expansion; its purpose is to increase bandwidth under the condition of the frequency. When you try to work with 802.11a products (frequency is 5 GHz), you must understand that they can only work with products based on exactly the same chipset, but cannot work directly with 802.11b products, unless you have one available At 802.11b, it is useful for 802.11a. To fully review Wi-Fi frequency and standard collaborative work ability, please read
The 802.11g standard - IEEE and
The Abcs of 802.11.
When considering your Linux wireless device driver, don't forget that the driver will not always implement the full features of the corresponding Window driver. This limits the ability to work together. On Linux, security features are especially easy to backward. The next section describes some details on enhancement and management.
Flexibility and wireless plan
In order to enable wireless networks to have flexibility and secure security, some plans have been initiated, such as Wireless Freenetwork Allocations and NodeDb.com (see Resources for more information). Basically, these are all sites where they can list their location and information about access points or fixed client connectivity, so others can easily position themselves based on a geodic directory service.
Linux's soul - its open, user is the spirit of owner and manager - has an impact in some wireless plans, regardless of whether Linux is indeed part of the solution. In some plans, such as nodedb.com, Linux is just one of the platforms. In Wiana and Nocatauth plans, it is a planned backbone because it has the ability to customize privileges at the operating system level (which is on the access point level).
Wiana
Wireless Assigned Numbers Authority is also known as WIANA program (see Resources for more information), which attempts to create a structure for wireless address management. Traditional IP address registry relies on a static score structure, which does not meet wireless applications. WiANA must handle special features of the wireless network, in the wireless network, the node only moves from one level from one level because of the change in the position. Under WiANA's guidelines, the management network is user rather than the provider. Large-scale Wi-Fi is based on a physical medium different from a traditional Internet. The high connection fees in the traditional Internet make the wireless user no longer use the same method to get IP addresses. In WiANA, these addresses are available free of charge. WIANA also tries to concentrate on the processing of abuse and blocking. WIANA supports compatible wireless software and hardware that are constrained by the mission declaration provided by LocustWorld.com. Those hardware and software are designed to be completely compatible with 802.11 Wi-Fi on any platform. The main idea is to provide open community wireless WAN, which are managed by users to give users more flexibility.
Nocatauth
You can think that the plan named NOCATAUTH is also a similar plan. It initially constructs to support Sonoma County, California's 802.11b wireless network. This implementation method will form a shared Internet service of the authentication code to a possible point (similar to WIANA). In order to follow an open source license to use NOCATAUTH, Perl programming languages, GNU Make, and GPGV must be installed in your Linux system. Linux's wireless future
Linux has become one of the options platforms such as Bluez (Running on Linux Kernel 2.4 and 2.6) and Linux-Irda and other products and solutions, and is also a platform for mobile phones. With the more powerful and mature mobile phone hardware, it will provide a huge opportunity for smaller providers, allowing them to create components that are easy to use and provide users with more powerful control of the environment. Most Linux phones have been applied in Asia where Linux is becoming the first choice for the 3G telephone development platform. The reason is very simple - Linux approaches to developers and consumers with greater flexibility and freedom.
Reference
- View wirelessly running SUSE PROFESSIONAL 9.0
Linux Storage Server.
- IBM
Linux Portal demonstrates how IBM software running on Linux can meet your needs.
- Investigate how IBM Linux server
Support Qualcomm wireless results.
- IBM
The BlueDrekar project helped the bridge between Linux and Bluetooth.
- If you are trying to build a Linux-based AP, then you need to read
Wireless Access Point Howto.
- After reading Howto, please continue reading
Build a wireless access point on Linux (DeveloperWorks, July 2003).
- To learn more about Linux and Wi-Fi networks, please read
Wireless lanhow. This page is also specially given
Wireless Lan Hardware Survey.
- understand deeper
Wireless Assigned Numbers Authority, or WIANA, is a plan to ensure the easy-to-use and stable operation of wireless addresses.
- View
Community Wireless project, it is an organization that describes wireless community networks.
-
LocustWorld helps install a worldwide wireless network.
- understand deeper
Nodedb This wireless node database project.
-
The target of the NOCATNET project is to generate a community-supported Wi-Fi network in Sonoma County. NOCATAUTH is the project's certification client.
-
Freenetworks.org organizes a lot of free networks in the world to prevent conflicts and duplication of IP addresses.
- Learn
RF ProPagation (PDF format) Basic concept.
- understand deeper
Rose Net Access Point Development Kit (PDF format).
- View SourceForge
The home page of the Linux-Irda project.
- To learn more about Irda and Bluez, please read
Linux Wireless Network Technology (DeveloperWorks, March 2004).
-
KwifiManager is a set of KDE tools using wireless extensions.
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WaproAMD is an automatic roaming Linux background program between access points.
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Aphunter is a Perl Packor for Linux Wireless Tools.
- understand deeper
Gwireless This wireless card configurator is used. GLINK is part of this project. - understand deeper
Host AP Driver This Linux driver for wireless LAN cards.
-
The 802.11g Standard - IEEE (DeveloperWorks, March 2003) introduced the formation and development trajectory of 802.11g.
-
The ABC's Of 802.11 (DeveloperWorks, Aug 2002) explains the agreement above 802.11.
-
Linux Emerging AS A Cell Phone Platform (Mobile Pipeline, May 2004) describes how mobile managers pay attention to Linux to meet their needs of more complex software without relying on large providers.
- Access
Developer Bookstore to get a detailed list of technical books, including hundreds of
Wireless related books.
- Immediately
Wireless zone tutorial page for from
DeveloperWorks' focus on wireless free tutorial fully list.
About author
Roman Vichr is a discipline expert who is committed to wireless technology and wireless robot technology. He provides solutions in this field for a variety of wealth 500 customers and has fun from it. In the past decade, the aspects of his interested include financial services, data sharing, and integration, Web services, and XML technology. You can pass
Roman@rdmax.com Contact him.
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