Are we allowed to reclasify a part 15 device for amateur use?
Equipment that has been certified for use in another service may be used on amateur frequencies by a licensed amateur as long as it meets all appropriate standards. (97.315) Hams of been repurposing Part 90 year for years.
Since wireless ethernet cards use a tcp/ip variant digital protocol to communicate is this legal?
Any digital code may be used as long as the technical characteristics are publicly documented. To further this, if commercial products are available that facilitate the transmission and reception of the communications incorporating these codes they are considered to be "specified." Therefore wireless ethernet is legitimate. Even if it were not publicly documented such as a homebrew protocol it would be classified as an unspecified digital code which is also permitted under [97.309(a)]
If we re-classify these wireless ethernet cards under Part 97, how do we legally ID?
Careful review of 97.119(3) shows that identification for data emissions may be made by transmitting your callsign using a specified digital code [see 97.309 (3) & (4)] such as ASCII, or you may ID by some other method that is publicly documented. I suggest embedding your callsign in a ping packet to be sent out every 10 minutes. Another method to embed your callsign within the ethernet datagram is to configure your callsign as part of your network name. Your callsign will at least be encapsulated inside an ethernet frame. This is perfectly acceptable and reasonable since the technical characteristics of wireless ethernet are publicly documented. The rules no longer really specify how you must ID. Anyone with a sniffer on the link will be able to see your callsign.
Is streaming/ transferring MP3's or other types of music over a wireless amateur data link permitted?
The music prohibition concerns the playing of music itself on the air as a phone emssion. So there is no problem here. Please refer to the famous 'trading of MIDI synthesizer commands over the air' example.
Are there any speed and or bandwidth constraints for data that we need to pay attention to?
Frequency Range Speed Limit for Maximum Bandwidth for Specified Codes Unspecified Codes 50.1 - 148 MHz 19.6 kilobauds 20 kHz 222 - 450 MHz 56 kilobauds 100 kHz Above 902 MHz No speed limit No bandwidth limit [97.307(f)(1)]Please note that with modulation like OFDM, these limits pertain to individual carriers not the cumulative sum. See: http://www.arrl.org/arrlletter?issue=2007-04-27
"In fact, 3 kHz bandwidth would have been a new limitation, because the present baud rate limit applies to individual carriers," he said. "Therefore, for emissions such as OFDM [orthogonal frequency-division multiplexing], which use multiple carriers, there is no effective bandwidth limit in the HF bands now." Sumner notes that under current rules, a single OFDM signal could conceivably -- and legally -- occupy an entire HF band.
Also see: http://www.qsl.net/kb9mwr/projects/wireless/70cm-ATV-HSMM.html
Wouldn't accessing a manufacturer's web site over an amateur data link violate 'no commercial' activity rules of ham radio? What about other content restrictions?
Since the rules now allow you to conduct commercial transactions (as long as they are only for your own private use), presumably you could even buy radio equipment on line from a manufacturer's website, as long as you instigated the transaction, not the store. I can't think of why this is any different that the famous "buying a pizza with an autopatch" case that was specifically decided by the FCC a number of years ago. Is there something about doing this via the Internet that would make it fundamentally different than doing it via an autopatch? [John, W2FS] As for other mythical content restrictions see 97.101a "each amateur station must be operated in accordance with good amateur practice." 97.311 lists prohibited transmissions. Basically unless you run your own business and have a pecuniary interest, or intend to access obscene/ indecent sites (defined by contemporary community standards for the broadcast medium), there shouldn't be any real issues. This shouldn't be an issue with a private network, a proxy filter may be a good idea if accessing internet sites.
As an amateur (Part 97) (internet) data link, only hams would be allowed to legally use it.
True, but I see no reason why someone else in your family (a third party) couldn't view web info over an amateur data link. As long as the responsible licensed amateur is supervising the operation (locally or remotely).
How would you limit access (to this repeater) to just hams?
All DSSS and FHSS systems have some sort of user setable security ID, which restricts what equipment talks to what. Also you can implement common TCP/IP tricks (firewalling, MAC address registration, ect) for further security. The ARRL proposed standardized WEP key for authentication.
As a Part 97 network we can't encrypt our network can we? What about eavesdroppers (people running sniffers) grabbing our passwords?
This probably isn't much of an issue for a private network, but I can see it being an issue when porting traffic over the internet. Keep in mind how the FCC rules are stated: "An amateur station shall not intentionally obscure the meaning ..." Encrypting just login & password strings doesn't obscure the meaning does it? Also using encryption can be classified as an "unspecified" digital code, which is permitted as long as you provide public documentation for it. Which can be fulfilled by posting your encryption key on your internet webpage, for example. Interesting to note that ham satellite command uplinks have been encrypted for years with the FCCs specific blessing ... all quite legal. The encryption's purpose is not to "obscure" but to provide security. Again this is furthered by the ARRL standardized WEP key used for authentication.
Article 25.2A (1A) at the 2003 World radio Conference no longer specifically prohibits the use of encryption and other strong security measures on transmissions between Amateur Radio stations within the same jurisdiction.
How about using 802.11b devices under ham radio authority in other countries? What are the rules?
According to Document BR68 for VK: (Australia/Great Britain), any emission mode/modulation technique is legal above 420 MHz, without any bandwidth restrictions. The identification requirement is basically the same as here in the USA. You need to ID using the same transmission type. So nesting your call in the ethernet datagram should fulfill this. (ASCII callsign beacons riding on UDP, or even 802.11b MAC address set to your callsign). Again VK allocations are much the same as in the USA. They have secondary allocations (to ISM) from 2400-2450 MHz. With a PEP of no more than 400W (26dBW). But if you're running an unattended system you have to: a) write a letter to the local RIS officer. b) Only run 14dBW (25W) ERP. In some countries in which authorized modes are not spelled out, you may need to reference the ITU emission classification. http://www.itu.int/radioclub/rr/aps01.htm The best anyone has come up with so far for 802.11b is: 22M0DXWWW, or possibly: 22M0DXWWC
Are 802.11a/g or other OFDM modes classified as Spread Spectrum?
No. A few years ago a company called WiLAN submitted an OFDM 802.11g
device to the FCC for certification under 15.247, arguing that, since it could
pass the "CW jammer test" (intended to assure that devices exhibited
the then-required 10 dB of process gain), it met the requirements of 15.247.
The FCC labs rejected the request for certification, stating that OFDM did not meet the definition of DSSS and therefore the device did not comply with the rules. See: http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-01-158A1.pdf