very simple question

[IanSeager]

When I try to access pprune, sometimes I get an error for pprune.org but get in with pprune.co.uk or visa versa, but tonight they both gave an error and I got in on pprune.com - what am I doing wrong?
TIA
Ian

[ExSimGuy]

What was the error mesage? Was it something like "server could be busy"? I do know that Danny has pprune.com, as well as pprune.org, presumably he now has pprune.co.uk (possibly as result of the host change a few months ago) so they are probably all redirected to the ".co.uk" and if the site was a bit overloaded when you happened to click, you got lucky when you tried one of the "redirections".

That's my guess, but I expect someone at "Towers" will be online soon to verify or correct!

Regards,

ESG

------------------
---- "Per Ardua ad Mixas" ----
(Through hardship to the bars)

(edited for lousy tryping!!)

[This message has been edited by ExSimGuy (edited 28 September 2000).]

[kanga]

I don't know if any of you noticed but there is a difference between .com and .org in the site's actual design.

[CrashDive]

Yeah, we also have PPRuNe.com and I'd suspect that PPRuNe.co.uk is a throwback to many years ago when our glorious site was hosted for us by Avnet in the UK - I think (... it was a looonnggggg time ago, and a lot's happened since then !).

Now when you enter the Unique Resource Locator (URL, aka the website address) of a site (e.g one of those above) what you're really saying to your Internet Service Provider (ISP) is "hey, where's the computer that runs the site called www.pprune.org (http://www.pprune.org) ? and connect me to it asap !"

Your ISP then has to resolve the URL (e.g www.pprune.co.uk) (http://www.pprune.co.uk)) into an Internet Protocol (IP) address (actually it's a TCP/IP address - a throwback to the Unix operating system).

Now the IP address is the real name/identifier of the computer you're trying to connect to; It's typically 4 group set, separated by fullstops, each of 3 numbers that uses octal (i.e a number system that uses 8 as it base, rather than decimal - which uses 10 - or binary - which
uses 2) .

Now to resolve the URL name to an IP number your ISP makes a call/request to a Domain Name Service (DNS) which has a HUGE list of the all the servers in the world (or a cross-reference list to other DNS's) and for want of a better expression is like a telephone diectory of (URL) names against (IP) numbers for the web.

Eg. www.pprune.org (http://www.pprune.org) is, fundamentally, hosted on a machine more properly identified as 216.157.75.152 (Ok, it's actually a tadge more complex than that, but in effect this is what happens on ALL web sites ! )

Thus, theoretically, what you can do is to type the IP address in rather than the URL and this should speed up site access as it no-longer has to undertake the time consuming cross-reference lookup of URL to IP via the DNS.

Now as an end user one of the more interesting things that you can do is to run a 'trace route' program.
What this shows you is the routing taking across the WWW when you enter either a URL or IP address (coz, they're really one and the same) - and a straight line it is not !

Eg. I just checked that to access the www.pprune.org (http://www.pprune.org) server from my home here in Lewes/SouthEast England takes a hop across 19 intermediate servers (5 in the UK - 14 in the USA) - all at the 60% of the speed of light - you hope !

If you're interested, I highly recommend a program called 'Neo Trace' for this !!!
(Can be found at: NeoTrace (http://www.neoworx.com/goonline/ntcurs.asp))
This program will also help you to visualise why the web might going slow and where it is that bottlenecks are occuring.

Now, the web is much like a neural network and so each node (server) determines (to some extent) the best route for it to take between itself and the server you're trying to connect too (like I said before, not necessarily a straight line !) .

Thus, and getting back to the original topic for this thread. Dependant upon where you are, and the ISP that you're connected to, and the preferences of it's DNS, and its networking architecture, will result in potentially differing paths to the end-result server (eg. the one that hosts PPRuNe) and thus may result in some being able to get access and others not.

Nb. More often than you may realise, this is much dependant on whether Charlie Farnsbarns has just dug through the fibre-optic cable just outside your ISP office, or indeed ISP's any along the routing chain that your ISP is promoting !

As clear as mud, ain't it ?!

[CrashDive]

On the .com .org thing...

Now, obviously(?), in the normal run of things .org's are non profit making organisations, whereas .com's or .co.uk's etc are in it for the money.

Some time ago Danny/Captain PPRuNe wisely registered both domain names, so that we'd subsequently retain ownership - and be able to use them accordingly.

As far as you lot are concerned when/if you connect to www.pprune.com (http://www.pprune.com) that server redirects you to www.pprune.org (http://www.pprune.org) automatically.

Ps. I just did another 'trace route', using NeoTrace, and this morning the connection is now traversing across 22 servers before it finally arrives at www.pprune.org (http://www.pprune.org) - and taking an average of 197 thousand's of a second from leaving my machine to arriving in PPRuNe land.