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So, I've almost always run my getting to be, ancient, Dell XPS 430 64bit computer with two screens. So, I frequently will answer an email, or comment on a blog by opening the original blog on one screen and then opening the same blog on the other screen for purposes of answering said blog, or email.
So, I am wondering how it is possible to view the same URL twice on the same computer and have it not get terribly confused?
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The computer and browser
The computer and browser treats the connections as different sessions. It's like opening the same document in two different copies of the same program and so on. It's taken care of on a different layer of the computer, probably the "network" layer.
And if you don't know what those are, don't worry about it. Only die hard geeks know what the OSI model is.
The OSI layers
The transport layer of the OSI Model assigns any new outgoing network request a unique source port number.
The easiest way to explain this is say you have 2 windows open, one for BCTS and another for say Stardust.
When you click on a new link your browser send a request to retrieve a HTML page found at that address from a server out on the internet. That outgoing network request once it reaches the transport layer is assigned a source port number and that number is unique to that window. when the server replies to that request it will include the source port number that it received so when the web page is received by your computer it will know what window to send the web page to. That is why you can have a hundred different browser windows open at the same time with different pages on each because both Windows and the OSI model work to try and keep each separate and unique.
I hope I did not just confuse you more.
hugs
Aspin
It works with many websites ...
... as long as you use only one browser window for actually inputting something (e.g. writing mail, ordering goods, ...) and use all the other windows only for reading.
But there are websites out there that get confused even with this method, and generally don't work properly if you open them in more than one browser window.
Sometimes it helps to use different browsers (open the URL in Internet Explorer and then again in Firefox, for example).
--- Martin
It's Magic!
The simple answer, is it works, some of the time. And some of the time, it doesn't.
As long as a webpage doesn't contain active content, that is, stuff that is updating depending on what you're doing, or on what is being streamed by the site, then each page view is just a static snapshot in time. The website doesn't know, or care, if you're still looking at it on the screen, or not. It was downloaded onto your screen when you clicked on it, and... there it is.
But, if you're using a website with all kinds of cookies and security stuff, and context-sensitive behavior, like an electronic bill-paying site would have, yeah, it'll get pretty confused if you're running two sessions on the same browser.
More geeky answer bits: Sometimes, the page is "cached" somewhere in the pipeline, like maybe your browser, or by your internet service provider, and you can load the page a zillion times, and the website only saw you did it once.
So, basically, if we sum all this up: it's magic!
This answer I can understand. :)
Magik. that makes sense. :)
In simpler terms...
Each time you open your browser, the computer sets aside some of it's resources to handle that beast... and under MOST circumstances the two don't ever talk to each other - or even know the other exists any more than your browser knows your word processor is running.
Now, web sites have gotten "smarter" (their term...) over the years and they keep some track of who you are, where you've been, what you've done and even what others have done (more lately than before)... Sometimes the place they "save" that info is right there on your computer (Cookies... And, no, not the chocolate chip kind). Sometimes they save the data on their end. Some of these "too smart for their own good" web sites send your browser updates on what it's already sent you after time (Like if you're using google mail, you can sit there looking at the screen, and you see new messages come in without hitting the refresh button to go look again.).
As mentioned most of the time all is well in this world... However, some of those "smart" web sites aren't as smart as they think... They "assume" (we all know what that makes...) that you only have one browser open and you have it pointed at them... When you have two, both pointed at that site, it's possible for actions in one window to muck up what's going on in another (that saved data I mentioned).
You never know how smart the website you're using is, until you try thing and they break.
Hope this helps,
Annette