IP Numbers

[ExSp33db1rd]

Is there an "IP Numbers for Dummies" guide book,or similar ?

I ask because Mrs. ExS is trying to make a booking for a few months hence, and using one of these evil websites that increases the price every time she visits the site.

She suggested that if she should now use my laptop instead of the desktop that she more usually uses, or take the laptop to California - which is going to happen anyway this year - in either case would the site now think she was someone new, and start her off again at the lower price, or show the same IP number that the spies on the website are recording for her now ?

I assumed so, as I've been under the impression that an IP number was unique to each and every computer, but then checked the IP number of our two home computers, one desktop and one laptop and Lo! they were the same, showing me being in my New Zealand village by name.

'tis a puzzlement.

Having got a headache sorting out masses of information that I obtained from Giggle, all I can come up with is that the Modem (router ? ) that we use at home feeds both computers, one via a hardwire Ethernet cable and one WiFi, and it is the IP number of that gadget that the outside World is noting, not individual computer numbers, hence, should we take a computer to California then our IP number recorded would be the one relevant to Starbucks WiFi outlet, if that is what we might use. N'est ce pas ?

For now I'm trying to persuade Mrs Exs. to "remove cookies and history" every time she signs off from the website that she is perusing, but is that enough ?

I'm confused because I've played around with ExpatShield and the like,which assigns an IP number to my computer - or does it do it to the Modem - that bears no relation to my present location, so that I can view BBC iPlayer outside the UK for instance, so would that also help fool the money-grabbing website from assuming Mrs ExS. is the same person again and trying to extort a higher price second,third, or fourth time around on her frequent enquiries ?

Words of one syllable please !

I blame Bill Gates !

[Saab Dastard]

all I can come up with is that the Modem (router ? ) that we use at home feeds both computers, one via a hardwire Ethernet cable and one WiFi, and it is the IP number of that gadget that the outside World is noting, not individual computer numbers

Correct. The public IP address of the router, assigned by your ISP, is what the website is looking at - plus cookies, potentially.

should we take a computer to California then our IP number recorded would be the one relevant to Starbucks WiFi outlet, if that is what we might use. N'est ce pas ?

Again correct. You could achieve the same effect by asking a neighbour or friend if you could drop in and use their internet connection - or by using a 3g / 4g device instead of your ISP internet connection.

You may be able to change your router's IP address by switching off your router for several hours until the DHCP lease expires (assuming it's dynamically assigned by your ISP, and the lease period is in hours, not days - outside your control, however).

I'm confused because I've played around with ExpatShield and the like,which assigns an IP number to my computer - or does it do it to the Modem - that bears no relation to my present location

No, it does neither. It simply proxies your connection, relaying your traffic to the target website via another router / computer in the remote country location. That would work once, but again the IP address would become known to the booking site. It's possible that your ExpatShield IP address might change, but only within a relatively small pool.

You could look into anonymiser providers, such as TOR, but you are getting into slightly murky waters. They would give your internet connection a seemingly remote egress point - much like ExpatShield - but randomly at some TOR exit point somewhere in the world, and this exit point would probably be different each time you used it.

SD

[llondel]

If it was me, I'd refuse to do business with a site that increased the price merely because I came back for a second look. To me that's too much like a scam and I wouldn't trust them.

You can also check your router and see what MAC address it has assigned to the WAN interface. If it will let you change that, you should see a new IP address assigned when you reboot it. Or (b), depending on your ISP, it might decide that it's not the MAC address it was expecting and throw you off completely. There is a finite chance that if you manage to change it to something that matched another device on the ISP's local subnet that it'll confuse the hell out of things, but that's a millions-to-one chance.

(Don't worry if the acronyms are gobbledegook, you should at least recognise them on a typical router web interface.)

[mixture]

ExSp33db1rd,


I ask because Mrs. ExS is trying to make a booking for a few months hence, and using one of these evil websites that increases the price every time she visits the site.


You're getting your knickers in a twist over IP addresses, and llondel is banging on (in a likely incorrect form) about MAC addresses.....

All you need to do is clear your cache and cookies !

[llondel]

All you need to do is clear your cache and cookies ! I thought he said he'd tried deleting the browser stuff, but re-reading, he was trying to get his missus to do it so perhaps not.

As for the MAC address, if it's a cable connection, changing it is the only quick and easy way of encouraging the ISP's DHCP server to give you a different IP address. Not sure how it works with ADSL, I've only ever has static IPs on those :8

[alisoncc]

It is my understanding that websites very rarely keep a record of anonymous accesses. Any retained data is kept on the Users computer in the form of cookies and cached data.

I use Firefox/Mozilla and daily I go through the cookies deleting all those that do not contain data I wish to keep like login passwords. I have also set my cache at zero megabytes. A number of newspapers that seek to limit free access are thus thwarted in their task.

If you request a "quote" by entering data into a form, by submitting it you have in effect registered an interest which is logged against your IP address. My local library provides 30 mins of free time per login for library registered users. It might be worth trying there if you have such a facility.

I run a couple of webservers in-house. Both utilise Awstats for analysis of traffic and I also get to see the raw access logs from Apache. MAC addresses never get a mention. No such data is passed to the server in a "wget" command.

You cannot change the MAC address of an interface. The MAC address is a hardware address encoded by the manufacturer in the chip used by the interface.

[Booglebox]

You cannot change the MAC address of an interface

Au contraire :E and it's a good way to get around airport wi-fi time limits

[mixture]

MAC addresses never get a mention.

Of course they won't !

Look up the definition of a MAC address.

Its OSI layer 2 !

[alisoncc]

From Wikipedia and I concur.

MAC addresses are most often assigned by the manufacturer of a network interface controller (http://en.wikipedia.org/wiki/Network_interface_controller) (NIC) and are stored in its hardware, such as the card's read-only memory (http://en.wikipedia.org/wiki/Read-only_memory) or some other firmware (http://en.wikipedia.org/wiki/Firmware) mechanism. If assigned by the manufacturer, a MAC address usually encodes the manufacturer's registered identification number and may be referred to as the burned-in address (BIA). It may also be known as an Ethernet hardware address (EHA), hardware address or physical address. This can be contrasted to a programmed address, where the host device issues commands to the NIC to use an arbitrary address.


A network node (http://en.wikipedia.org/wiki/Network_node) may have multiple NICs and each must have one unique MAC address per NIC.


MAC addresses are formed according to the rules of one of three numbering name spaces managed by the Institute of Electrical and Electronics Engineers (http://en.wikipedia.org/wiki/Institute_of_Electrical_and_Electronics_Engineers) (IEEE): MAC-48, EUI-48, and EUI-64. The IEEE claims trademarks (http://en.wikipedia.org/wiki/Trademark) on the names EUI-48 and EUI-64, in which EUI is an abbreviation for Extended Unique Identifier.
Your router maps the NIC MAC address to an internal IP address similar to the following ARP table:

http://users.on.net/~alisoncc/arptable.JPG

Note a MAC address usually encodes the manufacturer's registered identification number and may be referred to as the burned-in address (BIA). It may also be known as an Ethernet hardware address (EHA), hardware address or physical address.

Sure you can change it. Just reef the chip out and solder in a new one.

[Saab Dastard]

Lets clear up a couple of points:

1) MAC addresses have nothing to do with the OP's question.

2) MAC addresses can, in most circumstances, be programmatically assigned, i.e. the OS can override and replace the hardware MAC address with an arbitrary software MAC address.

SD

[alisoncc]

2) MAC addresses can, in most circumstances, be programmatically assigned, i.e. the OS can override and replace the hardware MAC address with an arbitrary software MAC address.Negative Sir. Only in very high end hardware can MAC addresses be programmatically re-assigned. In the above ARP table 50:e5:49 relates to the manufacturer of the NIC chip used on Gigabyte Motherboards. In the examples shown in the ARP table Realtek PCIe GBE Family Controllers.

In my recent experience with a few top-end HP servers and possibly even the Dell boxes the MAC addresses were fixed by the chip manufacturer. I have heard that some Cisco routers enable their MAC addresses to be changed, but not on your average Joe Public kit. Some systems allow a sysadmin to mask a MAC address, but it doesn't change the underlying address, only what appears to the system temporarily.

I agree MAC addresses have nothing to do with the OP's original issue.

[mixture]

Only in very high end hardware can MAC addresses be programmatically re-assigned.

Rubbish, rubbish, rubbish and rubbish.

Just because you don't know how to do it (or your choice of operating system doesn't easily provide the facility to do so), doesn't mean you can't do it.

[Saab Dastard]

This can be contrasted to a programmed address, where the host device issues commands to the NIC to use an arbitrary address.

The above is what you quoted yourself, alisoncc.

By change, we don't mean altering the hardware MAC address, we mean using the NIC driver software to assign a replacement MAC address.

You can change the MAC address in every version of Windows, at least since Windows 95 and NT server 3.5, and that's on anything from the cheapest PC to rack-mounted servers.

In fact, many SOHO broadband routers allow you to do this (my Linksys does), as it frequently used to be necessary for the router to spoof the MAC address of the PC that first registered the broadband connection with the ISP. Fortunately, those days are largely behind us.

I'm afraid, old chap, that mixture has summed it up in one word - rubbish.

SD

[ExSp33db1rd]

Thanks guys. I'll keep out of the MAC argument ! but am trying to persuade Mrs. ExS to set her browser to auto. delete cookies on exit, or I will occasionally do it myself when I can get near the desktop ( that's why I bought my own laptop ! )


[If it was me, I'd refuse to do business with a site that increased the price merely because I came back for a second look. To me that's too much like a scam and I wouldn't trust them.]


There are many, we are booking a Europe whistle-stop later this year, and she has found hotels, air fares, and presently Eurostar ticket brokers London-Paris who practice this iniquity. Eurostar is particularly evil, apparently - ( I'm keeping out of the exercise at the moment ! ) they appear to make bookings available no more than 6 months ahead, and once posted the price increases by the minute as the tickets are applied for, she is going to be poised, with credit card ready, 1 millisecond after Midnight plus 6 months on the appointed day to get the best rate - so she tells me.


[I have also set my cache at zero megabytes.]


Sounds a good idea, I'll look at that, too.


Thanks again, approaching 80 it's all too much ! I blame Bill Gates.

[cattletruck]

Love the thread drift into MAC land.

Its OSI layer 2 !
Yep, and that means the router will remove the frame from the packet and replace it with its own, meaning the packet now has the routers MAC address on the internet. And as that packet continues getting re-routed on it's journey to its destination it keeps on getting a new MAC address.

From memory, to change a MAC address on a Windoze PC just requires you to make a small change to the network policy and then you can go to network properties and there is a new tab available that allows you to enter any MAC address you like. This is a commonly used trick to re-activate licenses restricted to MAC address (rare now) when the network card dies and is replaced and the reseller that sold the original license has disappeared.

Now back to the OP's question.

Don't fiddle with cache, cookies etc. Just run your browser in anonymous/private mode.

On a side note, I found I could continually vote for a pop star friend who was on tour in the US and engaged in marketting obligations by simply clearing the cookies and voting again. I got her to second place :p.

[golfbananajam]

I didn't think you could change a MAC address either as I've always been taught they are hard wired and manufacturer specific..............but..........a quick google revealed


How do I change my MAC address?

Although physical MAC (Media Access Control) addresses are permanent by design, several mechanisms allow modification, or "spoofing", of the MAC address that is reported by the operating system. This can be useful for privacy reasons, for instance when connecting to a Wi-Fi hotspot, or to ensure interoperability. Some internet service providers bind their service to a specific MAC address; if the user then changes their network card or intends to install a router, the service won't work anymore. Changing the MAC address of the new interface will solve the problem. Similarly, some software licenses are bound to a specific MAC address. Changing the MAC address in this way is not permanent: after a reboot, it will revert to the MAC address physically stored in the card. A MAC address is 48 bits in length.

As a MAC address can be changed, it can be unwise to rely on this as a single method of authentication. IEEE 802.1x is an emerging standard better suited to authenticating devices at a low level.

Mac OS X

Under Mac OS X, the MAC address can be altered in a fashion similar to the Linux and FreeBSD methods:

sudo ifconfig en0 lladdr 00:01:02:03:04:05

or

sudo ifconfig en0 ether 00:01:02:03:04:05

This must be done as the superuser and only works for the computer's ethernet card. Instructions on spoofing AirPort Extreme (2.0) cards are available here. There are not, as of yet, any known ways to spoof original AirPort (1.0) cards.

The AirPort Extreme MAC address can also be changed easily with SpoofMac.

Windows

Under Windows XP, the MAC address can be changed in the Ethernet adapter's Properties menu, in the Advanced tab, as "MAC Address", "Locally Administered Address", "Ethernet Address" or "Network Address". The exact name depends on the Ethernet driver used; not all drivers support changing the MAC address in this way.

However, a better solution - requiring Administrative User Rights - is to pass over the System Registry Keys under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4 D36E972-E325-11CE-BFC1-08002BE10318}. Here settings for each network interface can be found. The contents of the string value called 'NetworkAddress' will be used to set the MAC address of the adapter when next it is enabled. Resetting the adapter can be accomplished in script with the freely available command line utility devcon from Microsoft, or from the adapters context menu in the Network Connections control panel applet.

There is a nice tool to change the MAC address for all cards (even those that can't be changed through the adapter's Properties menu): SMAC MAC Address Changer

Note: to check your MAC address easily on a Windows XP box, go to Run, type CMD, then type "ipconfig /all" without quotation in the command prompt. The number under physical address is the MAC address. If multiple IP are displayed, you should look under the label "Ethernet adapter x", where x is the name of your connection (which is Local Area Connection by default).

Router

The method to change the MAC address of a router varies with the router. Not all routers have the ability to change their MAC address. The feature is often referred to as "clone MAC address". This take the MAC address of one of the machine on your network and replaces the router's existing MAC address with it. Some support the option to manually enter the MAC address

[mixture]

This must be done as the superuser

Just for the record....

"sudo" stands for SuperUser Do !

No need to mess around actually logging in as super user.

[ExSp33db1rd]

[Don't fiddle with cache, cookies etc. Just run your browser in anonymous/private mode.]


?? Doesn't this mean that you can't then access sites that DEMAND that you receive cookies ?

[mixture]

?? Doesn't this mean that you can't then access sites that DEMAND that you receive cookies ?

Assuming its referring to the sort of blocking I'm thinking of, indeed it does. I've tried that trick.... sometimes it works, but it depends how reliant the sites are on cookies.

[cattletruck]

?? Doesn't this mean that you can't then access sites that DEMAND that you receive cookies ?

Better explained here:
https://support.mozilla.org/en-US/kb/private-browsing-browse-web-without-saving-info

My past experience with private browsing using the old FF 3.x was that under the hood it stored everything (cache, cookies, etc) in a separate temporary location until the browser was closed. This meant that any cookies received during a private browsing session remained functional until the browser was closed. I haven't done any private browsing in FF 26 as I'm now in the habit of clearing cache, cookies, etc when I close the browser (only got 200Mb free on my 4Gb SSD disk, it's time for a new lappie anyway).

[Sunnyjohn]

The browser SRW Iron has an incognito window facility. The search engine Duckduckgo has a private browsing facility. Use these two and you won't have to worry about MAC, BOOTS or GLOVES (OK, I'll get me hat . . .)

[Keef]

I doubt if the remote site is looking at your MAC address.
I would be surprised if it were using your IP address.
It may be using a cookie to detect a repeat visitor.

The more likely scenario is that it's like some companies I deal with (the local railway company is one) where they offer so many seats at "not a lot", then some at "a bit more" and so on, until on the day of travel you pay the full fare.
If I book to go to London in a month's time, I can probably get a ticket for £8 to £12. If I book for next week, it will be around £20. If I pitch up at the station on the day it will be around £60.

If the memsahib sees a price increase from site visit to site visit, I would suggest it's probably to do with the date and time of the visit.

[mixture]

I doubt if the remote site is looking at your MAC address.
I would be surprised if it were using your IP address.
It may be using a cookie to detect a repeat visitor.

With 99.9999999999999999999999999999999999999% confidence, I can tell you it'll be number three.

Number one is not technically possible, at all, ever. MAC addresses are OSI Layer 2. So we can rule that one out 100% guaranteed.

Number two is technically possible, but rather pointless to do, because of the effects of firewalls hiding multiple independent users (e.g. people at work surfing behind the corporate firewall).... hence most e-commerce websites will only use IP addresses as part of their fraud prevention measures at payment stage.... they are unlikely to use it during pricing (other than perhaps to automatically try to figure out which country you are in).

Hence we're left with number 3, cookies ( or their HTML5 equivalent, local or session storage).

[ExSp33db1rd]

[ Hence we're left with number 3, cookies .......]


So ....... do we deny cookies, and are then denied further progress, or immediately delete cookies at the end of the visit ?


Isn't the latter choice pointless anyway, having had to allow cookies for the visit isn't that then recorded against us, and when we next visit, and have to allow cookies again, they say Ah! Hah ! here they come again, we'll screw them now ?


Dunno, it all smells of sharp practice to me, if the first "not a lot" price gives them the operating profit that they require, and I don't believe that they will operate at a loss, "Loss leaders" not withstanding, then all the future increases are just usuary in my book. Bar stewards.

[Saab Dastard]

Cookies are stored on your PC, not their server.

SD

[Keef]

I think my number 4 is the most likely. As time passes, the "special offer" prices fade away. It depends, of course, on what the product is...

[ExSp33db1rd]

[As time passes, the "special offer" prices fade away.]


Agreed, my point exactly.


I doubt that Loss Leaders are actually a "loss", more likely a "Less Profit Leader", but then I've never been in retail marketing, so don't know, and don't really care, all I know is that if "they" are prepared to sell at the initial price, then that is the right price as far as I'm concerned and anything higher is just screwing me, like trying to get me to buy the "Large economy" size at a greater price then two half-sized packets, but I'm on to that. I'm on to this other practice as well, but not yet worked out how to beat it.


"Sometimes" - I have a choice, but sadly not always.


Life's a constant battle. "All 'tWorld's queer 'cept thee an' me, an' I'm none so sure 'bout thee" !!

[mixture]

So ....... do we deny cookies, and are then denied further progress, or immediately delete cookies at the end of the visit ?

As you rightly say, don't deny cookies because 99% of e-commerce websites these days rely on cookies for some degree of functionality.... its vary rare (if not technically impossible) to find one that doesn't because HTTP is a stateless protocol, so to make things like shopping carts work, cookies (or a technical alternative) are very much required.

So what you should to is have your web browser configured to automatically delete cookies upon close. Then that's done for you, and if you have the need to delete your cookies sooner than browser close, then you can do that yourself manually.

[ExSp33db1rd]

[...........then you can do that yourself manually.]


Thanks, I think the price hike is probably not necessarily specific to ones personal visits, but is a reflection of the overall interest, as in "hey, looks like we're on a winner here, so let's sock it to them " in which case removing ones' own cookies is like a drop in the ocean to the result.


Still, every bit helps.

[llondel]

There's confusion about the MAC address. My original reason for mentioning it is that changing it is a quick way of getting a DHCP server to give you a different IP address when you reboot or at least restart your network interface and request an IP address. It's extremely unlikely that anything outside your local network knows anything about your MAC address.

Now, if you're using IPv6 that might not be true...