- cypherpunks-legacy - lists.cpunks.org

Wireless Routing, Position Inference (was Re: CNN.com - WiFi activists on free Web crusade)
by Major Variola (ret) 02 Dec '02

02 Dec '02

At 02:57 PM 12/2/02 +0000, Peter Fairbrother wrote: > >What I don't understand is how a node knows the location of a person who >moves about in the first place. > >Also, I don't like the idea that my location is known by the location of my >equipment. But I know very little about geographical routing. I'll bite. Lets think about fundamentals, and play the adversary game. If I know that you can receive in *any wireless* system, then I know something about your location. This includes nets with huge 'cells', like a 100,000 watt commercial broadcast station (are you listening to KFOO or WFOO?), and nets with smaller cells, like the 'cellular' phones and 802.11foo meshes. The only difference (albeit a significant one) is the size of the cell ---the smaller your cells the more bits I get about your location. (Barring cypherpunk jokesters who make cell calls from the foci of dishes to hit another base station...) Of course if you're needing to transmit, you give your location. If you're needing to receive, and you roam beyond the diameter of a single 'cell', you are going to have to transmit your location (think cell phones) for routing XOR the system has no routing and must broadcast to all cells (think pagers) (you might consider the physical cells merged into a large single virtual cell in this case.). This latter doesn't scale. ---- Got Yagis?

1 0

Re: A couple of book questions...(one of them about Completeness)
by Tyler Durden 02 Dec '02

02 Dec '02

>That any particular string can be -precisely- defined as truth or false >as required by the definition of completeness, is what is not possible. Here we come down to what appears to be at the heart of the confusion as far as I see it. "True", depending on who's saying it (even in a discussion of Godelian Completeness), may be different. Mathematical types may define "true" as being "provably true", meaning something like "this statement can be derived from the other statements in my system by building up from logic plus the fundamental axioms". In Godel, in any formal system there are statements that are true but unprovable in that system. This would seem to render the notion of "true" above meaningless. But what it means in a "practical" sense is that there may be truisms (such as, "there exists no solution to the problem of a^n + b^n = c^n, where a,b,c and n are integers and n>2"), which are true (and let's face it, this statement is either true or false) but which can not be proven given the fundamental axioms of the system. Thus, in order to build more mathematics with this "truth", it must be incoroprated as an axiom. (Godel also says that after this "incoporation" is done, there will now be new unprovable statements.) I originally mentioned Godel in the context of the notion of the dificulty of factoring large numbers. My point was that its possible that... 1) Factoring is inherently difficult to do, and no mathematical advances will ever change that. and 2) We may never be able to PROVE 1 above. Thus, we may have to forever live with the uncertainty of the difficulty of factorization. _________________________________________________________________ The new MSN 8: smart spam protection and 2 months FREE* http://join.msn.com/?page=features/junkmail

1 0

Re: CNN.com - WiFi activists on free Web crusade - Nov. 29, 2002 (fwd)
by David Howe 02 Dec '02

02 Dec '02

at Monday, December 02, 2002 8:42 AM, Eugen Leitl <eugen(a)leitl.org> was seen to say: > No, an orthogonal identifier is sufficient. In fact, DNS loc would be > a good start. I think what I am trying to say is - given a "normal" internet user using IPv4 software that wants to connect to someone "in the cloud", how does he identify *to his software* the machine in the cloud if that machine is not given a unique IP address? few if any IPv4 packages can address anything more complex than a IPv4 dotted quad (or if given a DNS name, will resolve same to a dotted quad) > The system can negotiate whatever routing method it uses. If the node > doesn't understand geographic routing, it falls back to legacy > methods. odds are good that "cloud" nodes will be fully aware of geographic routing (there are obviously issues there though; given a node that is geographically "closer" to the required destination, but does not have a valid path to it, purely geographic routing will fail and fail badly; it may also be that the optimum route is a longer but less congested (and therefore higher bandwidth) path than the direct one. For a mental image, imagine a circular "cloud" with a H shaped hole in it; think about routing between the "pockets" at top and bottom of the H, now imagine a narrow (low bandwidth) bridge across the crossbar (which is a "high cost" path for traffic). How do you handle these two cases?

1 0

Re: CNN.com - WiFi activists on free Web crusade - Nov. 29, 2002 (fwd)
by Eugen Leitl 02 Dec '02

02 Dec '02

On Sat, 30 Nov 2002, Dave Howe wrote: > without routing and name services, you have what amounts to a propriatory I believe I mentioned geographic routing (which is actually switching, and not routing) so your packets get delivered, as the crow flies. The question of name services. How often do you actually use a domain name as an end user? Not very often. People typically use a search engine. It doesn't matter how the URI looks like, as long as it can be clicked on, or is short enough to be cut and pasted, or written down on a piece of paper and entered manually, in a pinch. So you need (distributed) searching and document (not machine) address spaces, which current P2P suites create the architecture for. > NAT solution - no way to address an interior node on the cloud from the It depends on how large the network is. Wireless is potentially a much bigger node cloud, so the current Internet could became a 'proprietary niche' eventually. However, there is no reason why the nodes wouldn't have a second address, or the IPv6 address would double as a geographic coordinate. At least during the migration. > internet (and hence, peer to peer services or any other protocol that > requires an inbound connection not directly understood by the nat > translation - eg ftp on a non standard port or ssl-encrypted as ftps) Fear not. > under ipv6 you can avoid having to have a explicit naming service - the You obviously understand under naming service something other than DNS. > cloud id of the card (possibly with a network prefix to identify the cloud > as a whole) can *be* the unique name; routing is still an issue but that Anything which relies on global routing tables and their refresh will always has an issue. Which is why geographical local-knowledge routing will dominate global networks. > reduces to being able to route to a unique node inside the cloud - which > appears from a brief glance at the notes from Morlock Elloi (thanks again :) > to have at least a workable trial solution. if a IPv6 internet ever becomes > a reality, clouds would fit right in. It is a patch, not a solution. But wireless ad hoc meshes are really a first real reason to go IPv6. > TCP/IP tunnelling without a name service at at least one end isn't workable; > *static* NAT/PAT is of course a name service and can't be considered, but > SOCKS and socks aware p2p is a definite possibility. The best solution would seem to leave the multilingual node the choice of means of delivery. It would be completely transparent to the packet.

2 2

Re: Question on P=NP
by Peter Wayner 02 Dec '02

02 Dec '02

At 8:55 AM -0800 12/1/02, Sarad AV wrote: >hi, > >Is the problem P=NP or not 'Decidable'. I don't even think we know. I vaguely remember someone saying that it would be really fascinating if it turned out not to be decidable. -Peter

1 0

Re: CNN.com - WiFi activists on free Web crusade - Nov. 29, 2002 (fwd)
by Tyler Durden 01 Dec '02

01 Dec '02

"Photons are bosons, so they don't interact with each other. Photon detectors can and usually have anisotropic sensitivity. Sure you can never beat fiber, but line of sight is free..." Well, by interfere I meant in the detectors of course. So are you telling me that two WiFi receivers pointed in different directions will not receive the same information? I don't think WiFi (IR) is all that directional is it? If it is, then maybe we CAN have a new LAN segment. >From: Eugen Leitl <eugen(a)leitl.org> >To: Tyler Durden <camera_lumina(a)hotmail.com> >CC: <cypherpunks(a)lne.com> >Subject: Re: CNN.com - WiFi activists on free Web crusade - Nov. 29, 2002 >(fwd) >Date: Sun, 1 Dec 2002 11:39:37 +0100 (CET) > >On Sat, 30 Nov 2002, Tyler Durden wrote: > > > I just don't see how a single WiFi cloud will be able to scale very far. >All > > the WiFi users within "eyeshot" of each other are always going to >contend > > for bandwidth, no? It'll be just like the old half-duplex 10BaseT copper > >There is limited bandwidth within a cell, if you use omni radiators. How >high is the limit? No one knows, but you can get 100 MBits/s with current >ultrabroadband prototypes. Then you have stuff like > > http://www.mobileinfo.com/News_2002/Issue05/NTT_2.5gps.htm > >Wireless Transfer Rate of 10 Gbps Possible, NTT says > >Always stretching the boundaries of wireless communications is Japanese >telecom NTT. > >The company?s most recent accomplishment was achieving a peak data >transfer rate of 2.5 Gbps, breaking the recorded rate of 1 Gbps; NTT >researchers now believe they will eventually break the 10 Gbps barrier. > >As the airwaves become increasingly congested, exploring uncharted >airwaves could pay NTT high dividends in the future. > >As an article in ComputerWire explains, NTT's solution has been to harness >new electronic and optical technologies to access the empty 120 GHz radio >band. Optical systems are used to generate the original signal which is >passed, using amplitude modulation to a 300 GHz photodiode, which creates >an electrical signal that is passed to a direct slot antenna. The key to >the whole process is the 300 GHz photodiode, which harnesses optical >technology, in this case the Lithium Niobate substrate originally designed >for light switching, to the business of generating an electrical signal. > >Commercial viability is still a ways off. At the moment, the sustained >1.25 Gbps signal generates a range of only 50 cm. Nevertheless, as demand >for wireless services out strips available spectrum, NTT will no doubt >find itself swarmed by partners and competitors alike. > >Then, you have funky stuff like antenna arrays. People have started >tinkering on MEMS galvanometers lately, which would allow to use line of >sight lasers across free space without need for manual alignment; possibly >dynamically tracking moving objects. > > > LANs. And I still don't understand how a WiFi router will help you...if >the > >Current routers use an omni to cover local area, and directional aeries to >create a mesh with their peers. Directional aerials for long-range >connections have both a longer range and are less sensitive to crosstalk >from the omni. > > > different Layer2 LANs overlap in space at all, they'll interfere with >each > > other optically even if they are on different segments. (With copper you > >Photons are bosons, so they don't interact with each other. Photon >detectors can and usually have anisotropic sensitivity. Sure you can never >beat fiber, but line of sight is free... > > > didn't even have this problem.) Thus, aren't you stuck with zillions o > > little WiFi islands that must not overlap without things getting very >slow? > >No. > > > As for service providers not wanting freeloaders, I'd point out that DSL > > "cares" much less....the DSL connection is mapped over ATM and is >basically > >If I have a P2P infrastructure run on end-user owned hardware (little >boxes glued to windowpanes) across an urban area with ~100 MBps/cell there >is not all that much use for an ISP. > >Things only become difficult if you want to crosslink cities. Here you >have to use fiber, or similiar. > > > a dedicated connection to a router port, with fixed bandwidth in either > > direction. Whether that port is processing lots of freeloader packets or > > idle packets from a single dedicated user shouldn't matter much. > > > > Uh, but now that I think of it ATM does allow for some oversubscription, >so > > in order to maximize the conection between the DSLAM and the ATM switch > > that's in front of the router (it might be in thesame box as the router, >I > > know!), maybe they'l discourage freeloading. BUT, DSL companies have >been > > touting that they're very happy for you to put a home-based LAN on your >side > > of the connection (Cable Modem providers don't normally like that). _________________________________________________________________ Help STOP SPAM with the new MSN 8 and get 2 months FREE* http://join.msn.com/?page=features/junkmail

1 0

Re: CNN.com - WiFi activists on free Web crusade - Nov. 29, 2002 (fwd)
by Eugen Leitl 01 Dec '02

01 Dec '02

On Sat, 30 Nov 2002, Tyler Durden wrote: > I just don't see how a single WiFi cloud will be able to scale very far. All > the WiFi users within "eyeshot" of each other are always going to contend > for bandwidth, no? It'll be just like the old half-duplex 10BaseT copper There is limited bandwidth within a cell, if you use omni radiators. How high is the limit? No one knows, but you can get 100 MBits/s with current ultrabroadband prototypes. Then you have stuff like http://www.mobileinfo.com/News_2002/Issue05/NTT_2.5gps.htm Wireless Transfer Rate of 10 Gbps Possible, NTT says Always stretching the boundaries of wireless communications is Japanese telecom NTT. The company?s most recent accomplishment was achieving a peak data transfer rate of 2.5 Gbps, breaking the recorded rate of 1 Gbps; NTT researchers now believe they will eventually break the 10 Gbps barrier. As the airwaves become increasingly congested, exploring uncharted airwaves could pay NTT high dividends in the future. As an article in ComputerWire explains, NTT's solution has been to harness new electronic and optical technologies to access the empty 120 GHz radio band. Optical systems are used to generate the original signal which is passed, using amplitude modulation to a 300 GHz photodiode, which creates an electrical signal that is passed to a direct slot antenna. The key to the whole process is the 300 GHz photodiode, which harnesses optical technology, in this case the Lithium Niobate substrate originally designed for light switching, to the business of generating an electrical signal. Commercial viability is still a ways off. At the moment, the sustained 1.25 Gbps signal generates a range of only 50 cm. Nevertheless, as demand for wireless services out strips available spectrum, NTT will no doubt find itself swarmed by partners and competitors alike. Then, you have funky stuff like antenna arrays. People have started tinkering on MEMS galvanometers lately, which would allow to use line of sight lasers across free space without need for manual alignment; possibly dynamically tracking moving objects. > LANs. And I still don't understand how a WiFi router will help you...if the Current routers use an omni to cover local area, and directional aeries to create a mesh with their peers. Directional aerials for long-range connections have both a longer range and are less sensitive to crosstalk from the omni. > different Layer2 LANs overlap in space at all, they'll interfere with each > other optically even if they are on different segments. (With copper you Photons are bosons, so they don't interact with each other. Photon detectors can and usually have anisotropic sensitivity. Sure you can never beat fiber, but line of sight is free... > didn't even have this problem.) Thus, aren't you stuck with zillions o > little WiFi islands that must not overlap without things getting very slow? No. > As for service providers not wanting freeloaders, I'd point out that DSL > "cares" much less....the DSL connection is mapped over ATM and is basically If I have a P2P infrastructure run on end-user owned hardware (little boxes glued to windowpanes) across an urban area with ~100 MBps/cell there is not all that much use for an ISP. Things only become difficult if you want to crosslink cities. Here you have to use fiber, or similiar. > a dedicated connection to a router port, with fixed bandwidth in either > direction. Whether that port is processing lots of freeloader packets or > idle packets from a single dedicated user shouldn't matter much. > > Uh, but now that I think of it ATM does allow for some oversubscription, so > in order to maximize the conection between the DSLAM and the ATM switch > that's in front of the router (it might be in thesame box as the router, I > know!), maybe they'l discourage freeloading. BUT, DSL companies have been > touting that they're very happy for you to put a home-based LAN on your side > of the connection (Cable Modem providers don't normally like that).

1 0

Re: The CDR as a Cliological experiment
by Tyler Durden 01 Dec '02

01 Dec '02

"(Tyler Durden, _please_ learn to trim your replies. Your "quote the entire thing" top posting is getting tiresome. I hear there are night school classes which teach Outlook Express or whichever braindead mailer you are using.)" Damn are you grumpy Tim May. Whaddya usin', carrier pigeon to download messages? (Or does some form of carpal tunnel make it excruciatingly painful to scroll down?) As for the historical references to the slave trade, I am finding that black folks are almost equally in the dark about history as whites in this country. And as my father has said... "The only thing stupider than a stupid black guy is a stupid white guy." And... "Wherever two or more Americans are gathered have ye a lynch mob." _________________________________________________________________ STOP MORE SPAM with the new MSN 8 and get 2 months FREE* http://join.msn.com/?page=features/junkmail

2 1

Re: The CDR as a Cliological experiment
by Tim May 30 Nov '02

30 Nov '02

On Saturday, November 30, 2002, at 05:23 PM, Tyler Durden wrote: > As far as I'm concerned, most strife boils down to the perceived > economic interests of the concerned parties, and apparently > ehtnic/religious/whatever differences are just a mask for these > simpler problems. As a big for instance, racism during the slavery > days was really a way to allow for economic explouitation of "human > resources"...slavetraders of course searched for Biblical and > Darwinian justification of their actions, and codified them into their > "religion". The slave trade was centered around some negroes capturing and selling some other negroes. The Moslems who ferried the captured negroes along the coast were just middlemen, as were the Dutch and English who carried the negro cargo to the final customers. Ironically, the negro in America, especially the negro Muslim, blames the Jew for what other negroes and other Muslims did to some of his ancestors. And now the negro in America wants the "honkey" to give him reparations. (Tyler Durden, _please_ learn to trim your replies. Your "quote the entire thing" top posting is getting tiresome. I hear there are night school classes which teach Outlook Express or whichever braindead mailer you are using.) --Tim May

1 0

Re: CNN.com - WiFi activists on free Web crusade - Nov. 29, 2002 (fwd)
by Dave Howe 30 Nov '02

30 Nov '02

Morlock Elloi wrote: > Not so. Self-organasing mesh networks appear to have some interesting > properties. There is a number of open solutions and at least one > startup I know about based on this. <snip links> fascinating - I obviously have a lot of reading to do - thankyou :)

1 0