NY ranks #1 in Internet b/w
Perhaps Sept 11 was no coincidence and perhaps they knew of these numbers as well. -Hank http://www.totaltele.com/view.asp?ArticleID=45236&pub=tt&categoryid=626 New York is the Internet capital - TeleGeography By Total Telecom staff 30 October 2001 New York is the world's Internet capital in terms of bandwidth connectivity, according to Washington DC-based research group TeleGeography Inc. With almost 150 Gbps of region-to-region bandwidth connectivity, the Big Apple is hooked up to more than two-thirds of all interregional Internet capacity worldwide. London comes a long way second, with just over 85 Gbps. According to the TeleGeography report, Packet Geography 2002, New York has direct connections into 71 other countries, 10 more than London. The report ranks global Internet cities according to their roles as "interregional hub cities," measuring how much Internet capacity links them to other world regions. After NY and London, Amsterdam, Paris, and San Francisco complete the Internet global city top five. In all, five of the top 10 cities are in the U.S., four are in Europe, and one, Tokyo, is in Asia. Although Europe and Asia each have major hub locations, most Internet traffic between Asia and Europe still traverses U.S. coast-to-coast routes. Indeed, according to the report, 13 of the top 25 companies providing international Internet connections in the U.S. are based outside of North America. The Top 10 in full is: 1. New York (149,989.5 Mbps of Internet bandwidth) 2. London (85,518.7 Mbps) 3. Amsterdam (24,479.6 Mbps) 4. Paris (22,551.8 Mbps) 5. San Francisco (20,813.6 Mbps) 6. Tokyo (16,745.5 Mbps) 7. Washington DC (13,261.2 Mbps) 8. Miami (11,912.4 Mbps) 9. Los Angeles (11,227.0 Mbps) 10. Copenhagen (10,417.0 Mbps) Note: Figures represent Internet bandwidth connected across international borders to Consolidated Metropolitan Statistical Areas or equivalents. Domestic routes are omitted. Data as of mid-2001. This report can be purchased through Total Telecom's 'Reports and Research' resource. Click here for more details.
But if you look at trunks going into *another* country the same report comes to this ranking. London Paris New York Amsterdam Frankfurt This report also says that the relevance of US for Internet is decreasing. As ever: never trust a statistic unless you faked it yourself ... -- Arnold ----- Original Message ----- From: "Hank Nussbacher" <hank@att.net.il> To: <nanog@merit.edu> Sent: Wednesday, October 31, 2001 8:41 AM Subject: NY ranks #1 in Internet b/w
Perhaps Sept 11 was no coincidence and perhaps they knew of these numbers as well. -Hank
http://www.totaltele.com/view.asp?ArticleID=45236&pub=tt&categoryid=626
New York is the Internet capital - TeleGeography By Total Telecom staff
30 October 2001
New York is the world's Internet capital in terms of bandwidth connectivity, according to Washington DC-based research group
Inc.
With almost 150 Gbps of region-to-region bandwidth connectivity, the Big Apple is hooked up to more than two-thirds of all interregional Internet capacity worldwide. London comes a long way second, with just over 85 Gbps.
According to the TeleGeography report, Packet Geography 2002, New York has direct connections into 71 other countries, 10 more than London.
The report ranks global Internet cities according to their roles as "interregional hub cities," measuring how much Internet capacity links
TeleGeography them
to other world regions. After NY and London, Amsterdam, Paris, and San Francisco complete the Internet global city top five.
In all, five of the top 10 cities are in the U.S., four are in Europe, and one, Tokyo, is in Asia. Although Europe and Asia each have major hub locations, most Internet traffic between Asia and Europe still traverses U.S. coast-to-coast routes. Indeed, according to the report, 13 of the top 25 companies providing international Internet connections in the U.S. are based outside of North America.
The Top 10 in full is:
1. New York (149,989.5 Mbps of Internet bandwidth) 2. London (85,518.7 Mbps) 3. Amsterdam (24,479.6 Mbps) 4. Paris (22,551.8 Mbps) 5. San Francisco (20,813.6 Mbps) 6. Tokyo (16,745.5 Mbps) 7. Washington DC (13,261.2 Mbps) 8. Miami (11,912.4 Mbps) 9. Los Angeles (11,227.0 Mbps) 10. Copenhagen (10,417.0 Mbps) Note: Figures represent Internet bandwidth connected across international borders to Consolidated Metropolitan Statistical Areas or equivalents. Domestic routes are omitted. Data as of mid-2001.
This report can be purchased through Total Telecom's 'Reports and Research' resource. Click here for more details.
On Wed, 31 Oct 2001, Nipper, Arnold wrote:
But if you look at trunks going into *another* country the same report comes to this ranking.
London Paris New York Amsterdam Frankfurt
This report also says that the relevance of US for Internet is decreasing.
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time. Are there subs that can lay undersea cables yet? A cable from Northern Europe to Japan and the US North West under the North Pole icecap would be great.
As ever: never trust a statistic unless you faked it yourself ...
But one thing is obvious: we IP people put our stuff where we think we want it, not where it should go looking from a redundancy/vulnerability standpoint. If I want to send a packet from The Hague to Philadelphia, the packet will almost certainly pass Amsterdam and New York, two places where huge amounts of traffic can easily be disrupted. If the IP routers were to be placed closer to the places where seacables surface, this problem would go away: all those major hubs are serviced by multiple fiber landing locations.
that can lay undersea cables yet? A cable from Northern Europe to Japan and the US North West under the North Pole icecap would be great.
Don't know about the icecaps -- the Middle East will probably have more demand than the North Pole for a long long time -- but I think FLAG has some bandwidth they'd like to sell you (http://www.flagtelecom.com/cable_route.htm). As might the telcos who own SeaMeWe-3 (http://smw3.fcr.fr/SMW/SMWB2.htm)... So:
This report also says that the relevance of US for Internet is decreasing.
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time.
Yes, but at least you can see traces from S Korea to Japan, say, which don't route through Palo Alto. Region-to-region is harder. cheers Bram
On Fri, 2 Nov 2001, Bram Dov Abramson wrote:
that can lay undersea cables yet? A cable from Northern Europe to Japan and the US North West under the North Pole icecap would be great.
Don't know about the icecaps -- the Middle East will probably have more demand than the North Pole for a long long time -- but I think FLAG has some bandwidth they'd like to sell you (http://www.flagtelecom.com/cable_route.htm). As might the telcos who own SeaMeWe-3 (http://smw3.fcr.fr/SMW/SMWB2.htm)...
Obviously the big advantage of the Mediterranean/Red Sea/Indian Ocean route is that there are many countries along the way that can benefit from the cable. But if you want to go from London to Tokyo, it's not quite the shortest path: the great circle distance is 9600 km, but the FLAG is nearly three times that at 28000 km. That's even nearly 10000 km more than a London - New York - San Francisco - Tokyo route. The icecap route would be only 12000 km.
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time.
Yes, but at least you can see traces from S Korea to Japan, say, which don't route through Palo Alto. Region-to-region is harder.
Right. The problem is that it's hard to justify expensive connections to neighboring countries when: 1. You hardly exchange any traffic with them anyway (for instance, in The Netherlands it's about 45% domestic, 45% to/over the US and only 10% of the traffic goes to other European countries) 2. You need (and therefore have) a big pipe to the US anyway that can absorb this traffic easily It is extremely annoying when doing the right thing is too expensive.
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time. ...
You will find that there are many routes from Europe to Asia (and back again) that don't run via the US. Two examples... http://www.bbeng.gxn.net/cgi-bin/lg.pl?query=trace&addr=www.hkt.net&router=Amsterdam1 http://www.bbeng.gxn.net/cgi-bin/lg.pl?query=trace&addr=www.singnet.com.sg&router=Amsterdam1 I'm sure there are many more. There are a few cables that run between Europe and Asia (SMW3 and Flag) that are good communications routes for non-US-transiting traffic. Martin --------------------- At 01:09 PM 11/2/2001 +0100, Iljitsch van Beijnum wrote:
On Wed, 31 Oct 2001, Nipper, Arnold wrote:
But if you look at trunks going into *another* country the same report comes to this ranking.
London Paris New York Amsterdam Frankfurt
This report also says that the relevance of US for Internet is decreasing.
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time. Are there subs that can lay undersea cables yet? A cable from Northern Europe to Japan and the US North West under the North Pole icecap would be great.
As ever: never trust a statistic unless you faked it yourself ...
But one thing is obvious: we IP people put our stuff where we think we want it, not where it should go looking from a redundancy/vulnerability standpoint.
If I want to send a packet from The Hague to Philadelphia, the packet will almost certainly pass Amsterdam and New York, two places where huge amounts of traffic can easily be disrupted. If the IP routers were to be placed closer to the places where seacables surface, this problem would go away: all those major hubs are serviced by multiple fiber landing locations.
Apparently, there's no enough EU <-> AP traffic to justify direct circuits. The dispersion-shifted single-mode ground fiber (along the route of Trans-Siberian railroad) does exist. --vadim On Fri, 2 Nov 2001, Iljitsch van Beijnum wrote:
On Wed, 31 Oct 2001, Nipper, Arnold wrote:
But if you look at trunks going into *another* country the same report comes to this ranking.
London Paris New York Amsterdam Frankfurt
This report also says that the relevance of US for Internet is decreasing.
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time. Are there subs that can lay undersea cables yet? A cable from Northern Europe to Japan and the US North West under the North Pole icecap would be great.
As ever: never trust a statistic unless you faked it yourself ...
But one thing is obvious: we IP people put our stuff where we think we want it, not where it should go looking from a redundancy/vulnerability standpoint.
If I want to send a packet from The Hague to Philadelphia, the packet will almost certainly pass Amsterdam and New York, two places where huge amounts of traffic can easily be disrupted. If the IP routers were to be placed closer to the places where seacables surface, this problem would go away: all those major hubs are serviced by multiple fiber landing locations.
I don't know about AP/EU traffic, but I know that this trans-russion link is already saturated (they are thinking abiut moving to WDM). ----- Original Message ----- From: "Randy Bush" <randy@psg.com> To: "Vadim Antonov" <avg@exigengroup.com> Cc: "Iljitsch van Beijnum" <iljitsch@muada.com>; <nanog@merit.edu> Sent: Friday, November 02, 2001 3:32 PM Subject: Re: NY ranks #1 in Internet b/w
Apparently, there's no enough EU <-> AP traffic to justify direct circuits. The dispersion-shifted single-mode ground fiber (along the route of Trans-Siberian railroad) does exist.
as does flag
randy
On Fri, 2 Nov 2001, Iljitsch van Beijnum wrote:
On Wed, 31 Oct 2001, Nipper, Arnold wrote:
[snip]
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time.
[snip] Enjoy: - Traceroute from ppewww.ph.gla.ac.uk to 150.100.1.6 (sinet.ad.jp) Sorry, due to abuse of this server script by some remote Internet sites, we have had to disable the AS information, pending a more-effective anti-abuse solution. traceroute to 150.100.1.6 (150.100.1.6), 30 hops max, 38 byte packets 1 194.36.1.1 (194.36.1.1) 0.921 ms 0.862 ms 0.729 ms 2 130.209.2.1 (130.209.2.1) 1.016 ms 0.893 ms 0.889 ms 3 130.209.2.22 (130.209.2.22) 0.674 ms 0.777 ms 0.817 ms 4 scot-pop-west.ja.net (146.97.250.33) 1.840 ms 2.428 ms 2.408 ms 5 glasgow-bar.ja.net (146.97.37.25) 1.302 ms 1.221 ms 1.437 ms 6 pos9-0.glas-scr.ja.net (146.97.35.53) 1.494 ms 1.343 ms 1.392 ms 7 pos0-0.edin-scr.ja.net (146.97.33.22) 3.259 ms 2.631 ms 2.488 ms 8 pos0-0.leed-scr.ja.net (146.97.33.26) 8.147 ms 7.369 ms 8.432 ms 9 pos2-0.lond-scr.ja.net (146.97.33.30) 12.024 ms 12.211 ms 11.961 ms 10 london-bar2.ja.net (146.97.35.6) 12.378 ms 11.973 ms 12.099 ms 11 ten155-gw.ja.net (193.63.94.15) 12.781 ms 12.940 ms 12.753 ms 12 janet.uk.ten-155.net (212.1.192.149) 14.474 ms 18.835 ms 16.487 ms 13 212.1.192.186 (212.1.192.186) 303.626 ms 301.981 ms 303.517 ms 14 nacsis-2-FE2-0-0.sinet.ad.jp (150.99.99.17) 317.214 ms 313.987 ms 313.982 ms 15 otsuka-gate2-A3-0.sinet.ad.jp (150.100.126.1) 329.783 ms 315.773 ms 315.497 ms 16 * * * 17 * * * 18 * *
Rafi Sadowsky wrote:
On Fri, 2 Nov 2001, Iljitsch van Beijnum wrote:
On Wed, 31 Oct 2001, Nipper, Arnold wrote:
[snip]
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time.
Well, back in 1995 I connected a Japanese internet customer (the name escapes me) to BTnet in the UK. The connection method was frame relay and so at the IP layer there was one hop between London and Tokyo.... Nigel
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time.
and we should not forget carl malamud's ds3 around the world in the mid-90s. it was called park.org. not sure where to find info about it on the net today. randy
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time.
I see two :-) [Although these could in theory still go via the US]. collector.LINX.NET>traceroute www.pccw.com Translating "www.pccw.com"...domain server (195.66.232.34) [OK] Type escape sequence to abort. Tracing the route to www.pccw.com (202.153.117.7) 1 linx01.hkt.net (195.66.224.143) 4 msec 0 msec 0 msec 2 s6-0.tmhstcbr01.hkt.net (202.84.249.5) [AS 4637] 264 msec 264 msec 268 msec 3 207.176.97.134 [AS 4637] 264 msec 264 msec 264 msec 4 202.84.133.198 [AS 4637] 260 msec 264 msec 260 msec 5 f5-1.yckbr01.hkt.net (205.252.130.239) [AS 4637] 376 msec 412 msec 404 msec 6 202.84.133.78 [AS 4637] 276 msec 280 msec 272 msec 7 * * * collector.LINX.NET>traceroute www.singtel.com.sg Translating "www.singtel.com.sg"...domain server (195.66.232.34) [OK] Type escape sequence to abort. Tracing the route to www.singtel.com.sg (165.21.20.180) 1 linx1.ix.singtel.com (195.66.224.122) 4 msec 0 msec 4 msec 2 202.160.243.117 [AS 7473] 0 msec 4 msec 4 msec 3 Serial5-1.tp-core1.ix.singtel.com (202.160.250.245) [AS 7473] 196 msec 196 msec 196 msec 4 202.160.250.54 [AS 7473] 196 msec 196 msec 192 msec 5 FE-4-0.lavender.singnet.com.sg (165.21.12.17) [AS 3758] 192 msec 196 msec 196 msec 6 165.21.237.254 [AS 3758] 204 msec 196 msec 196 msec 7 * * * Regards, Neil.
Few folks I guess recall the dial-up line that ran westward from Beijing to Karlsruhe that functioned in the early-to-mid '80s. It ran at 300 baud. On good days. -s On Saturday 03 November 2001 16:55, Nigel Titley wrote:
Rafi Sadowsky wrote:
On Fri, 2 Nov 2001, Iljitsch van Beijnum wrote:
On Wed, 31 Oct 2001, Nipper, Arnold wrote:
[snip]
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time.
Well, back in 1995 I connected a Japanese internet customer (the name escapes me) to BTnet in the UK. The connection method was frame relay and so at the IP layer there was one hop between London and Tokyo....
Nigel
-- Stephen Wolff 202 362 7110 voice Office of the CTO 202 362 7224 fax Cisco Systems 202 427 6752 mobile
steve wolff wrote:
Few folks I guess recall the dial-up line that ran westward from Beijing to Karlsruhe that functioned in the early-to-mid '80s. It ran at 300 baud. On good days. -s
Steve, sure I do and Arnold Nipper on the list will as well since he I believe implemented it... Was it not 9.6? Later is X.25........ Dave
steve wolff wrote:
Few folks I guess recall the dial-up line that ran westward from Beijing
to
Karlsruhe that functioned in the early-to-mid '80s. It ran at 300 baud. On good days. -s
Steve, sure I do and Arnold Nipper on the list will as well since he I believe implemented it... Was it not 9.6? Later is X.25........
Dave, when I joined the team of Werner Zorn in '89 the "China connection" already was well established. -- Arnold Dave, just for the records: IIRC it were Michael Rotert, Gerd Wacker and Michael Finken (both now/still?? Conware) who set up the CSNET connection to Beijing. Must have been1985 or so.
At 9:44 AM -0500 11/5/01, steve wolff wrote:
Few folks I guess recall the dial-up line that ran westward from Beijing to Karlsruhe that functioned in the early-to-mid '80s. It ran at 300 baud. On good days. -s
That was an X.25 line, and I am not sure that it used IP atop the X.25. --SteveG --
Steve wrote:
At 9:44 AM -0500 11/5/01, steve wolff wrote:
Few folks I guess recall the dial-up line that ran westward from Beijing
to
Karlsruhe that functioned in the early-to-mid '80s. It ran at 300 baud. On good days. -s
That was an X.25 line, and I am not sure that it used IP atop the X.25. --SteveG
We ran CSNET/X.25 as we did to US. -- Arnold
Steve Wolff wrote:
Few folks I guess recall the dial-up line that ran westward from Beijing to Karlsruhe that functioned in the early-to-mid '80s. It ran at 300 baud. On good days. -s
It was an X.25 dial-up running at 9.6 kbit/s and was turned down 94/95 when IP connectivity to CN was well established. -- Arnold (former co-worker of Prof. Zorn)
I cheerfully stand corrected. Good thing mine's not the only memory at work here... -s On Mon, 5 Nov 2001, Nipper, Arnold wrote:
Date: Mon, 5 Nov 2001 17:02:14 +0100 From: "Nipper, Arnold" <arnold@nipper.de> To: swolff@cisco.com, Nigel Titley <nigel@titley.com>, nanog@merit.edu Subject: Re: NY ranks #1 in Internet b/w
Steve Wolff wrote:
Few folks I guess recall the dial-up line that ran westward from Beijing to Karlsruhe that functioned in the early-to-mid '80s. It ran at 300 baud. On good days. -s
It was an X.25 dial-up running at 9.6 kbit/s and was turned down 94/95 when IP connectivity to CN was well established.
-- Arnold (former co-worker of Prof. Zorn)
On Sat, 3 Nov 2001, Rafi Sadowsky wrote:
Hm, I'm still waiting to witness a traceroute from Europe to Asia or the Pacific that doesn't go over the US for the first time.
Enjoy:
Thank you. :-)
10 london-bar2.ja.net (146.97.35.6) 12.378 ms 11.973 ms 12.099 ms 11 ten155-gw.ja.net (193.63.94.15) 12.781 ms 12.940 ms 12.753 ms 12 janet.uk.ten-155.net (212.1.192.149) 14.474 ms 18.835 ms 16.487 ms 13 212.1.192.186 (212.1.192.186) 303.626 ms 301.981 ms 303.517 ms 14 nacsis-2-FE2-0-0.sinet.ad.jp (150.99.99.17) 317.214 ms 313.987 ms 313.982 ms
Unfortunately, in this instance avoiding the US doesn't seem to pay off: 5 so-1-1-0.TR1.AMS2.Alter.Net (146.188.8.86) 5.187 ms so-1-1-0.TR2.AMS2.Alter.Net (146.188.8.90) 309.476 ms 296.644 ms 6 so-2-0-0.IR2.DCA4.Alter.Net (146.188.11.222) 87.299 ms 86.886 ms 86.995 ms [...] 11 POS6-0.BR3.DCA6.ALTER.NET (152.63.38.117) 87.579 ms 86.699 ms 86.749 ms 12 a3-0.uunet.mclnva02.us.bb.verio.net (204.255.169.90) 320.341 ms 289.424 ms 291.342 ms 13 p16-0-0-0.r02.mclnva02.us.bb.verio.net (129.250.5.254) 291.258 ms 88.383 ms 88.220 ms 14 p4-6-1-0.r00.plalca01.us.bb.verio.net (129.250.2.245) 173.876 ms 173.900 ms 403.277 ms [...] 18 p1-1.nii.snjsca03.us.bb.verio.net (129.250.10.22) 595.339 ms 567.663 ms * 19 kyoto-10-GE2-0.sinet.ad.jp (150.99.163.65) 444.986 ms 397.353 ms 336.185 ms (I removed 4 UUNET routers in DC and 3 Verio routers in the Bay Area.) Over 300 ms for less than 10000 km (6000 miles) is not great. Even a good satellite should be able to provide better round trip times... But then the GSM cellular network provides a minimum RTT of 550 ms even for very short distances, so I suppose it could be worse.
Over 300 ms for less than 10000 km (6000 miles) is not great. Even a good satellite should be able to provide better round trip times...
That sounds somewhat erroneous. Geosynchronus orbit is about 22,500 miles; up+down+roundtrip makes that 22,500 * 4, or 90,000 miles; 90,000 / 186,000 miles/sec = 483 milliseconds, which, or course, due to routers inducing very measureable delay, and the fact that an IP Packet takes adds a little delay due to its lenght, is usually a bit more. When working on this stuff (specifically on a hop from Oslo to Jerusalem), I recall 630 ms being the average latency. But, to make my point, Geosync orbit could never, ever be less than 483 milliseconds, ever. -- Alex Rubenstein, AR97, K2AHR, alex@nac.net, latency, Al Reuben -- -- Net Access Corporation, 800-NET-ME-36, http://www.nac.net --
On Sun, 4 Nov 2001, Alex Rubenstein wrote:
Over 300 ms for less than 10000 km (6000 miles) is not great. Even a good satellite should be able to provide better round trip times...
That sounds somewhat erroneous. Geosynchronus orbit is about 22,500 miles; up+down+roundtrip makes that 22,500 * 4, or 90,000 miles; 90,000 / 186,000 miles/sec = 483 milliseconds, which, or course, due to routers inducing very measureable delay, and the fact that an IP Packet takes adds a little delay due to its lenght, is usually a bit more.
I'm afraid you're right. 240 ms is firmly burned into my mind, but this is the ONE WAY delay.
But, to make my point, Geosync orbit could never, ever be less than 483 milliseconds, ever.
Well, actually there is a caveat: the distance to the satellite is never exactly 22500 miles. Depending on whether the orbit is measured from the surface of the earth (which is obviously the case for regular non-geosynchronous satellites) or the center of the earth (which I think is done with the 22500 mi figure) the satellite is either farther away or closer, depending on the location of the observer and the orbit of the satellite. The difference is substantial: up to 4000 miles.
Well, actually there is a caveat: the distance to the satellite is never exactly 22500 miles. Depending on whether the orbit is measured from the surface of the earth (which is obviously the case for regular non-geosynchronous satellites) or the center of the earth (which I think is done with the 22500 mi figure) the satellite is either farther away or closer, depending on the location of the observer and the orbit of the satellite. The difference is substantial: up to 4000 miles.
geosynchronous orbit is 22500 miles from the *surface* of the earth. -- Brett
On Sun, 4 Nov 2001, Brett Frankenberger wrote:
Well, actually there is a caveat: the distance to the satellite is never exactly 22500 miles. Depending on whether the orbit is measured from the surface of the earth (which is obviously the case for regular non-geosynchronous satellites) or the center of the earth (which I think is done with the 22500 mi figure) the satellite is either farther away or closer, depending on the location of the observer and the orbit of the satellite. The difference is substantial: up to 4000 miles.
geosynchronous orbit is 22500 miles from the *surface* of the earth.
well sorta... it's ~35787km above mean sea-level which is around 22,366 miles. That altitude is about 42164km above a point represting the earths center of gravity on the equitorial plane. there's a copy of the wireless world (1945) article by arthur c clarke here: http://www.lsi.usp.br/~rbianchi/clarke/ACC.ETRelays.html the actual distance from you to the sattelite will vary based on your location but the distance from the point over the equater where it sits to the sattelite will remain constant...
-- Brett
-- -------------------------------------------------------------------------- Joel Jaeggli joelja@darkwing.uoregon.edu Academic User Services consult@gladstone.uoregon.edu PGP Key Fingerprint: 1DE9 8FCA 51FB 4195 B42A 9C32 A30D 121E -------------------------------------------------------------------------- It is clear that the arm of criticism cannot replace the criticism of arms. Karl Marx -- Introduction to the critique of Hegel's Philosophy of the right, 1843.
On Sun, 4 Nov 2001, Brett Frankenberger wrote:
is done with the 22500 mi figure) the satellite is either farther away or closer, depending on the location of the observer and the orbit of the satellite. The difference is substantial: up to 4000 miles.
geosynchronous orbit is 22500 miles from the *surface* of the earth.
Ok, this means if the satellite is just over the horizon it's actually 26500 miles away.
On Sun, 4 Nov 2001, Alex Rubenstein wrote:
That sounds somewhat erroneous. Geosynchronus orbit is about 22,500 miles; up+down+roundtrip makes that 22,500 * 4, or 90,000 miles; 90,000 / 186,000 miles/sec = 483 milliseconds, which, or course, due to routers inducing very measureable delay, and the fact that an IP Packet takes adds a little delay due to its lenght, is usually a bit more.
Practically, I know back in 1994 when I was in the US and the Nordic university network had a backup E3 satellite link I had to use, the round trip times were approx 600ms. 483ms round trip if you're at the equator, sounds like it can correlate fairly well to 600ms when you have to go from northern europe, to a satellite hanging up above the atlantic ocean, and then down to north america (or might even be so satellite over africa, then to satellite hanging over central america, then down to north america, ie two satellite hops). -- Mikael Abrahamsson email: swmike@swm.pp.se
participants (19)
-
Alex Rubenstein -
Alexei Roudnev -
Bram Dov Abramson -
Brett Frankenberger -
Dave Morton -
Hank Nussbacher -
Iljitsch van Beijnum -
Joel Jaeggli -
Martin J. Levy -
Mikael Abrahamsson -
neil＠DOMINO.ORG -
Nigel Titley -
Nipper, Arnold -
Rafi Sadowsky -
Randy Bush -
Stephen Wolff -
Steve Goldstein -
steve wolff
-
Vadim Antonov