Audio broadcast using 802.11 (ip radio)
Some terms from http://www.ic.gc.ca/eic/site/smt-gst.nsf/eng/sf08479.html#aa9
Master mode is an operating mode in which the LE-LAN device has the capability to transmit without receiving an enabling signal. In this mode, the device is able to select a channel and initiate a network by sending enabling signals to other LE-LAN devices.
Slave mode is an operating mode in which the transmissions of the LE-LAN device are under control of the master.
The real issue is to over come the required handshake (link between server and device) the device should always receive and the server should always deliver.
http://en.wikipedia.org/wikiwireless_LAN#Roaming
Roaming
Here is the research found on this type of software.
Roaming between Wireless Local Area Networks
There are 2 definitions for wireless LAN roaming:
• Internal Roaming (1): The Mobile Station (MS) moves from one access point (AP) to another AP within a home network because the signal strength is too weak. An authentication server (RADIUS) assumes the re-authentication of MS via 802.1x (e.g. with PEAP). The billing of QoS is in the home network. A Mobile Station roaming from one access point to another often interrupts the flow of data between the Mobile Station and an application connected to the network. The Mobile Station, for instance, periodically monitors the presence of alternative access points (ones that will provide a better connection). At some point, based upon proprietary mechanisms, the Mobile Station decides to re-associate with an access point having a stronger wireless signal. The Mobile Station, however, may lose a connection with an access point before associating with another access point. In order to provide reliable connections with applications, the Mobile Station must generally include software that provides session persistence.[11]
• External Roaming (2): The MS(client) moves into a WLAN of another Wireless Internet Service Provider (WISP) and takes their services (Hotspot). The user can independently of his home network use another foreign network, if this is open for visitors. There must be special authentication and billing systems for mobile services in a foreign network.
http://www.dailywireless.org/2004/06/28/ugly-truth-about-mesh-networks/
1- Radio is a shared medium and forces everyone to stay silent while one person holds the stage. Wired networks, on the other hand, can and do hold multiple simultaneous conversations.
http://en.wikipedia.org/wiki/Shared_mesh
http://en.wikipedia.org/wiki/802.16
http://en.wikipedia.org/wiki/FCC_Part_15
A Sip live audio feeding agent. The agent captures audio from sound card and sends live audio stream(uLaw) to caller(sip phone) using RTP. It is based on Peers 0.3(http://peers.sourceforge.net/). Can be used in IP telephony to broadcast live audio.
https://sourceforge.net/projects/sipaudiofeeding/
AirJack is a device driver (or suit of device drivers) for 802.11(a/b/g) raw frame injection and reception. It is ment as a development tool for all manor of 802.11 applications that need to access the raw protocol.
https://sourceforge.net/projects/airjack/
A simple Python program to simplify control of the AcerHK radio's -- Wifi and Bluetooth. It enables users to turn on / off the Bluetooth and Wifi Radios. It depends on the AcerHK driver to function.
https://sourceforge.net/projects/acerhkgui/
butt (broadcast using this tool) is an easy-to-use, multi-OS streaming tool. It supports ShoutCast and IceCast. butt runs on Linux, Mac OS, and Windows.
https://sourceforge.net/projects/butt/
This project aims to create an applet and panel tools to manage a wireless interface card, such as IEEE 802.11 cards. The development will focus on Linux, asthis is the most accessible platform, but will expand as we get access to more platforms
https://sourceforge.net/projects/gwifiapplet/
This software is provided as a proof of concept and demonstration of maintaining the presence of a number of radio based systems, such as 802.11. This is proof of concept.
http://erpres.sourceforge.net/
CGI-Wifi is a perl/CGI program designed to aid in the setup of Wireless cards in Linux Operating systems. It uses a user friendly interface to allow the user to completely manipulate the wireless setup files.
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https://sourceforge.net/projects/cgi-wifi/support
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apboot is a way for standard 802.11 access points to discover and bootstrap with a wireless LAN
This article describes the methods for wireless connections
http://www.vias.org/wirelessnetw/wndw_05_04.html
IEEE 802.11
Search sourceforge with the term WRT for a list of open source Router firmware including
the invitation to try these other free firmwares:
Wireless Networks
Before packets can be forwarded and routed to the Internet, layers one (the physical) and two (the data link) need to be connected. Without link local connectivity, network nodes cannot talk to each other and route packets.
To provide physical connectivity, wireless network devices must operate in the same part of the radio spectrum. As we saw in chapter two, this means that 802.11a radios will talk to 802.11a radios at around 5GHz, and 802.11b/g radios will talk to other 802.11b/g radios at around 2.4GHz. But an 802.11a device cannot interoperate with an 802.11b/g device, since they use completely different parts of the electromagnetic spectrum.
More specifically, wireless cards must agree on a common channel. If one 802.11b radio card is set to channel 2 while another is set to channel 11, then the radios cannot communicate with each other.
When two wireless cards are configured to use the same protocol on the same radio channel, then they are ready to negotiate data link layer connectivity.
Each 802.11a/b/g device can operate in one of four possible modes:
1. Master mode (also called AP or infrastructure mode) is used to create a service that looks like a traditional access point. The wireless card creates a network with a specified name (called the SSID) and channel, and offers network services on it. While in master mode, wireless cards manage all communications related to the network (authenticating wireless clients, handling channel contention, repeating packets, etc.) Wireless cards in master mode can only communicate with cards that are associated with it in managed mode.
2. Managed mode is sometimes also referred to as client mode. Wireless cards in managed mode will join a network created by a master, and will automatically change their channel to match it. They then present any necessary credentials to the master, and if those credentials are accepted, they are said to be associated with the master. Managed mode cards do not communicate with each other directly, and will only communicate with an associated master.
3. Ad-hoc mode creates a multipoint-to-multipoint network where there is no single master node or AP. In ad-hoc mode, each wireless card communicates directly with its neighbors. Nodes must be in range of each other to communicate, and must agree on a network name and channel.
4. Monitor mode is used by some tools (such as Kismet, chapter six) to passively listen to all radio traffic on a given channel. When in monitor mode, wireless cards transmit no data. This is useful for analyzing problems on a wireless link or observing spectrum usage in the local area. Monitor mode is not used for normal communications.
When implementing a point-to-point or point-to-multipoint link, one radio will typically operate in master mode, while the other(s) operate in managed mode. In a multipoint-to-multipoint mesh, the radios all operate in ad-hoc mode so that they can communicate with each other directly.
It is important to keep these modes in mind when designing your network layout. Remember that managed mode clients cannot communicate with each other directly, so it is likely that you will want to run a high repeater site in master or ad-hoc mode. As we will see later in this chapter, ad-hoc is more flexible but has a number of performance issues as compared to using the master / managed modes.
Now that your wireless cards are providing physical and data link connectivity, they are ready to start passing around packets on layer 3: the internet-working layer.
Hinternet and others working on this type of project
Often referred to as hinternet or High-speed_multimedia_radio
http://en.wikipedia.org/wiki/Talk:High-speed_multimedia_radio
Security != encryption
It's a common assumption that security requires encryption. Even the FCC seems to have this belief, given that it allows encryption in space command communications.
In fact this is incorrect. I've pointed this out to some people involved in HSMM work (and hope to write an article about it one of these days). Access control needs strong authentication. That can be done quite easily, without encryption of any kind. IPsec in authentication-only mode has all the necessary mechanisms.
I suspect in the HSMM context the picture gets muddled because there isn't an authentication-only mode in WEP or WPA. Then again, WEP at least is junk. WPA seems to be better, but personally I would just turn all that stuff off and rely on IPsec, which definitely has been designed by skilled cryptographers (unlike WEP).
73, ni1d. Paul Koning (talk) 02:28, 26 January 2008 (UTC)
I think the point is that if you've reason enough to use authentication, then you've reason enough to use encryption too. Correct me if I'm misunderstanding, but you wouldn't want anyone stealing your packets. --AB (talk) 00:40, 8 February 2008 (UTC)
Not necessarily. In network security they are different services and the reasons for using one vs. the other are not the same. In any case, amateur radio is a special case: by law, amateur radio communication is not allowed to hide the content of the communication. So encryption is prohibited. On the other hand, there is no prohibition on authentication, and in fact in some places the regulations imply you are supposed to use it (for example auxiliary links).
Also, what do you mean by "stealing your packets"? If it means (a) reading the contents -- then the answer is that the amateur radio service specifically requires that the contents be readable, and if you need to communicate something that shouldn't be publicly visible, your only option is to avoid the amateur radio service. If it means (b) having Y take a copy of the packets sent by X and pretend they were created by Y -- I agree, and that is precisely what authentication does. In fact, only authentication does that -- encryption alone does not. That's why the FCC's rule allowing encryption in space command traffic is flat out technically wrong. (See Bellovin, Steven M. (1996). "Problem Areas for the IP Security Protocols". Proceedings of the Sixth Usenix Unix Security Symposium. San Jose, CA. pp. 1-16. for a detailed explanation of that point.) Paul Koning (talk) 18:19, 8 February 2008 (UTC)
Pros and cons??
Can the article be edited to remove the Pros and Cons sections? It currently reads like a product review rather than an encyclopedia article.--Kharker (talk) 23:02, 26 February 2008 (UTC)
"Also AMSAT has requested that HSMM operators stay away from 802.11b/g channel 1 to prevent interference to satellite operations. It was recommended in CQ magazine that users use channels 3 and 5."
This is no longer the case. In an email from John Champa he said "When the "Channel 1 is Ver Botten" message (HI) was sent out there was an active Phase 3 OSCAR using that band segment. That is no longer the case. So that guideline is outdated. Forget about it. ;o)" Kmoravec (talk) 14:48, 15 May 2008 (UTC)Kmoravec
http://www.oreillynet.com/etel/blog/2003/01/enter_the_hinternet.html
Enter the Hinternet
* listen Speech Icon
Wednesday January 15, 2003 8:21PM
by Rob Flickenger
Hams are fascinating people. They have tremendous command of the art of wireless networking, and are very conscious of their community, and the importance of its place in the world.
Particularly interesting to me is where Hams and their networking efforts interface with the Community Networks agenda of bringing ubiquitous wireless networking to the masses.
The HSMM project seems to be a tremendous leap in a very exciting direction. If Hams and Part 15′ers can leverage each other’s experience and resources, all sorts of interesting possibilities open up. Imagine a coordinated effort to use Part 15 networks as client endpoints, and aggregate traffic through high-power (and high profile) Ham repeaters. Of course, we’ve imagined it before, and have always run up against a couple of basic tenets of Amateur operations that forbid such matter-of-course elements as encryption, commercial traffic, rebroadcasting of music, and even basic unattended third party communications. If the ARRL is behind interconnecting Ham networks with the Internet, then I must have misinterpreted the rules. I certainly hope so, and it’s very likely, as I’m still studying for my Technician Class license.
I just wrote to the organizers of HSMM (I’m just dying for more details), and hope to hear back soon…
Hardware
Open source hardware companies for example.
http://www.metrix.net/metrix-mark-ii-kit-p-14.html?zenid=e5026517007599d20e4e8ec53b8291a5
With a Mark II kit running Pyramid Linux, you have the ultimate in flexibility and performance without overloading your budget. With increased processing power and two radios, the potential applications are endless. Whether you need a Multi-band Access Point, an Active Repeater, a Core Infrastructure Node, an Advanced Wireless Portal, an Access Point also running Kismet for Rogue AP Detection, or a Dual Radio Mesh Network Node, the Mark II can do it all.
Need storage? Get the Mark II USB cable and add a hard drive, more flash, or just about any other USB device.
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