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SurferJoe46
26-04-2007, 11:53 AM
Wondering if typing in "xyx@silly.com" makes the connection slower than if I input the IP address instead?

Does the problem of resolving the URL actually affect the connection sped or not?

Is there any real latency involved either way...or are they both about the same?

The_End_Of_Reality
26-04-2007, 01:08 PM
In theory it would, but it is really not very noticable, and is only when you first goto a site, For example if you goto www.pressf1.co.nz, then the DNS looks up the IP address and then you have the IP address for the whole session, so if you goto PF1 (the forum) from the PF1 homepage it will not have to do another DNS lookup

SurferJoe46
26-04-2007, 01:18 PM
In theory it would, but it is really not very noticable, and is only when you first goto a site, For example if you goto www.pressf1.co.nz, then the DNS looks up the IP address and then you have the IP address for the whole session, so if you goto PF1 (the forum) from the PF1 homepage it will not have to do another DNS lookup

So is the DNS look-up result stored as a cookie? A prefetch?

If I set my cookies to delete after a session, then the look-up has to happen all over again...right?

The_End_Of_Reality
26-04-2007, 02:04 PM
I am not fully sure how it works, never looked into it, but what I said above is what I have picked up. It has nothing to do with cookies it is just something that happens :p

EDIT: have a look at http://www.dnsstuff.com/ and http://en.wikipedia.org/ they are bound to give you more info

Safari
26-04-2007, 03:43 PM
http://www.techiwarehouse.com/cms/engine.php?page_id=163e0b14

To help speed up Web browsing, Windows comes with a local cache containing any DNS addresses that have been looked up recently.

To clear the DNS cache
Open a command prompt and enter ipconfig /flushdns and the cache will emptied.

SurferJoe46
26-04-2007, 05:46 PM
http://www.techiwarehouse.com/cms/engine.php?page_id=163e0b14

To help speed up Web browsing, Windows comes with a local cache containing any DNS addresses that have been looked up recently.

To clear the DNS cache
Open a command prompt and enter ipconfig /flushdns and the cache will emptied.

Wow...here's something I learned tonight:

The default time period for keeping an address in the cache is 24 hours.

Thus, a problem can arise if the IP for an URL changes before the 24 hour period is up. In this case an error message will result if you try to connect to the URL.

It is not a frequent occurrence but is not unknown. Another more common problem can arise from URLs that are temporarily busy or from congested Internet traffic.

If a negative response is received from an attempt to connect, that result is also kept in the local cache. The default time period for retaining a negative response is five minutes.

In other words, once a negative response is received you will not be able to connect to the site for at least five more minutes.

Since temporary congestion lasting a few seconds is often the cause of a momentary inability to connect to a site, this delay of five minutes can be a nuisance.

Misty
21-02-2008, 08:14 PM
Wondering if typing in "xyx@silly.com" makes the connection slower than if I input the IP address instead?
From my very limited understanding the great advantage to the domain system is that a whole bunch of servers are used and if one server is down then the domain name will still be found by the rest. This would not happen if the IP address were used. Speed therefore is not the crucial factor in such a scenario.:2cents:

Is my understanding correct ? :nerd:
Misty

PaulD
21-02-2008, 08:37 PM
From my very limited understanding the great advantage to the domain system is that a whole bunch of servers are used and if one server is down then the domain name will still be found by the rest. This would not happen if the IP address were used. Speed therefore is not the crucial factor in such a scenario.:2cents:

Is my understanding correct ? :nerd:
Misty

No. The advantage of the DNS system is as you say that there are many servers but it's the IP address that is found. As Joe's found IP addresses associated with a Domain Name can change for many reasons.

The speed of DNS look up is usually nothing compared to the time taken to download all the advertising BS from most sites

gcarmich
21-02-2008, 08:58 PM
The multiple IP address lookup for DNS is a relatively new thing in the history of DNS. DNS (Domain Name System) was designed to make it easy to find (and remember) things, for example www.pressf1.co.nz is a lot easier to remember than 210.48.100.45. IP addresses are going to get even harder to remember as we start to move to the next version of IP (IPv6 – an example of which would be 0:0:0:0:0:ffff:192.1.56.10)

beeswax34
21-02-2008, 11:03 PM
From my very limited understanding the great advantage to the domain system is that a whole bunch of servers are used and if one server is down then the domain name will still be found by the rest. This would not happen if the IP address were used. Speed therefore is not the crucial factor in such a scenario.:2cents:

Is my understanding correct ? :nerd:
Misty

Yup, every single root server in the world and there's about 13 main physical ones and a couple of hundred that are hosted virtually all have the exact same comprehensive list of every IP address in the world.

gcarmich
22-02-2008, 06:55 AM
Thats not true. They are root servers, root meaning the bottom, they know how to find the next level up, and so on.

Take a look at http://www.howstuffworks.com/dns.htm

and http://www.faqs.org/docs/linux_network/x-087-2-resolv.howdnsworks.html