Dynamic IP

Hi,

This is probably a very simple question!

On a network which assigns IP's dynamically - if Computer A connects to
a website which logs their IP address - will it log their IP address OR
the web servers IP address??

Thanks,
Jack

In article <(E-Mail Removed) .com>,
jack-(E-Mail Removed) wrote:

> Hi,
>
> This is probably a very simple question!
>
> On a network which assigns IP's dynamically - if Computer A connects to
> a website which logs their IP address - will it log their IP address OR
> the web servers IP address??

It will log the client's IP address. Why would the web server log its
own address? How could the server behave differently depending on how
the client's IP was assigned? All it sees is a packet from an IP,
there's nothing in the packet that indicates how the IP was originally
assigned.

--
Barry Margolin, (E-Mail Removed)
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***
*** PLEASE don't copy me on replies, I'll read them in the group ***

Do you mean to ask, will it log the IP of the requesting ComputerA or the
IP address of the DHCP Server? If that is your question, I believe the
answer is neither. I believe it would record the IP of your internet
gateway.

<jack-(E-Mail Removed)> wrote in message
news:(E-Mail Removed) oups.com...

Hi,

This is probably a very simple question!

On a network which assigns IP's dynamically - if Computer A connects to
a website which logs their IP address - will it log their IP address OR
the web servers IP address??

Thanks,
Jack

Yes sorry that's exactly what I'm asking - so you think it records the
ip of the internet gateway?

i just received another answer saying it would record the client IP -
hmm.... i think you may be right.


KJS wrote:
> Do you mean to ask, will it log the IP of the requesting ComputerA or the
> IP address of the DHCP Server? If that is your question, I believe the
> answer is neither. I believe it would record the IP of your internet
> gateway.
>
> <jack-(E-Mail Removed)> wrote in message
> news:(E-Mail Removed) oups.com...
>
> Hi,
>
> This is probably a very simple question!
>
> On a network which assigns IP's dynamically - if Computer A connects to
> a website which logs their IP address - will it log their IP address OR
> the web servers IP address??
>
> Thanks,
> Jack

It will log the last PUBLIC IP in the chain. If it is your computer, so be
it. If your computer is using a private address via a pubic gateway (router
or firewall) it will log the gateway public address.

-Frank

<jack-(E-Mail Removed)> wrote in message
news:(E-Mail Removed) oups.com...
> Yes sorry that's exactly what I'm asking - so you think it records the
> ip of the internet gateway?
>
> i just received another answer saying it would record the client IP -
> hmm.... i think you may be right.
>
>
> KJS wrote:
>> Do you mean to ask, will it log the IP of the requesting ComputerA or the
>> IP address of the DHCP Server? If that is your question, I believe the
>> answer is neither. I believe it would record the IP of your internet
>> gateway.
>>
>> <jack-(E-Mail Removed)> wrote in message
>> news:(E-Mail Removed) oups.com...
>>
>> Hi,
>>
>> This is probably a very simple question!
>>
>> On a network which assigns IP's dynamically - if Computer A connects to
>> a website which logs their IP address - will it log their IP address OR
>> the web servers IP address??
>>
>> Thanks,
>> Jack
>

Barry Margolin wrote:
> In article <(E-Mail Removed) .com>,
> jack-(E-Mail Removed) wrote:
>
> > Hi,
> >
> > This is probably a very simple question!
> >
> > On a network which assigns IP's dynamically - if Computer A connects to
> > a website which logs their IP address - will it log their IP address OR
> > the web servers IP address??
>
> It will log the client's IP address. Why would the web server log its
> own address? How could the server behave differently depending on how
> the client's IP was assigned? All it sees is a packet from an IP,
> there's nothing in the packet that indicates how the IP was originally
> assigned.


Reading between the lines, I think the OP may have meant the address of
his proxy server or NAT box, and that he's conflating private addresses
with dynamic addresses.

If there's a proxy server, then yes, the web site would see its
address. In the case of NAT, the web site will see the external IP
address assigned, which is quite often one of the external ports on the
NAT box.

<(E-Mail Removed)> wrote in message
news:(E-Mail Removed) oups.com...
>
> Barry Margolin wrote:
>> In article <(E-Mail Removed) .com>,
>> jack-(E-Mail Removed) wrote:
>>
>> > Hi,
>> >
>> > This is probably a very simple question!
>> >
>> > On a network which assigns IP's dynamically - if Computer A connects to
>> > a website which logs their IP address - will it log their IP address OR
>> > the web servers IP address??
>>
>> It will log the client's IP address. Why would the web server log its
>> own address? How could the server behave differently depending on how
>> the client's IP was assigned? All it sees is a packet from an IP,
>> there's nothing in the packet that indicates how the IP was originally
>> assigned.
>
>
> Reading between the lines, I think the OP may have meant the address of
> his proxy server or NAT box, and that he's conflating private addresses
> with dynamic addresses.
>
> If there's a proxy server, then yes, the web site would see its
> address. In the case of NAT, the web site will see the external IP
> address assigned, which is quite often one of the external ports on the
> NAT box.
>

Yes, it is also important to note that "external" does not equate to
"public". Many networks use firewalls/routers totally inside their own
private address space. Each firewall/router still has an external and
internal interface.

External and Internal addresses are present in every firewall/router
(separate two or more networks).

Public and Private are not always present. Public equates to Internet
routable addresses and Private equates to Internet non-routable addresses.

This is an area where correct terminilogy is everything.

-Frank

In article <(E-Mail Removed)>,
Frankster <(E-Mail Removed)> wrote:

>Yes, it is also important to note that "external" does not equate to
>"public". Many networks use firewalls/routers totally inside their own
>private address space. Each firewall/router still has an external and
>internal interface.
>
>External and Internal addresses are present in every firewall/router
>(separate two or more networks).
>
>Public and Private are not always present. Public equates to Internet
>routable addresses and Private equates to Internet non-routable addresses.
>
>This is an area where correct terminilogy is everything.

If terminology matters, then it would be better to write
"RFC 1918 address" if that is what you mean by "Private."
The phrases "Internet routable addresses" and "Internet non-routable
addresses" are not well defined. There are many IP addresses that are
not listed in RFC 1918, not in 127.0.0.0/8, and neither class-D nor
class-E, but are not known to the community of default-free routers.
Some of those IP addresses are unassigned, but others are assigned and
routes to them could be advertised by BGP but are not.

If you really care about terms, it is also worth noting that by official
IETF dogma, all IP addresses are dynamically assigned. They differ
only in how soon they are likely to be reassigned. Everyone is supposed
to be prepared to renumber their networks sooner or later.

Note also that whether an interface's IP address is configured with
manual typing, reverse ARP, BOOTP, DHCP, PPP IPCP, or some other scheme
is not necessarily related to how "dynamic" the address is, or likely
it is to reassigned. Many computers with what most people consider
"static" IP addresses are configured with DHCP or PPP IPCP.


Vernon Schryver (E-Mail Removed)

> If terminology matters, then it would be better to write
> "RFC 1918 address" if that is what you mean by "Private."

No. Becaue I am not interested in pointing out the official reference for
where Private is defined. Only the definiation so as to provide clarity.

> The phrases "Internet routable addresses" and "Internet non-routable
> addresses" are not well defined. There are many IP addresses that are
> not listed in RFC 1918, not in 127.0.0.0/8, and neither class-D nor
> class-E, but are not known to the community of default-free routers.
> Some of those IP addresses are unassigned, but others are assigned and
> routes to them could be advertised by BGP but are not.

This was not relevant to this thread. But clarification of
Private/Public/Internal/External was relevant to understanding. Not much
point in providing a virtual Encyclopeia of RFCs to answer one post.

> If you really care about terms

I don't. I care about clear communication in regard to this post. Not the
terms themselves. Your post sounds like it was written by someone who cares
more about proving his knowledge than the subject at hand.

> Note also that whether an interface's IP address is configured with
> manual typing, reverse ARP, BOOTP, DHCP, PPP IPCP, or some other scheme
> is not necessarily related to how "dynamic" the address is, or likely
> it is to reassigned. Many computers with what most people consider
> "static" IP addresses are configured with DHCP or PPP IPCP.

Again, are you simply looking for debate? I never said anything that would
even vaguely refer to your statement above. Just espousing your knowledge?

-Frank

I have found two people that believe accurate terminology is important!!!
You are both my heros!

"Words mean things" and life would be so much better in these groups if
people took the time to use correct terminology is both the questions and
the answers,..but especially the questions.


"Vernon Schryver" <(E-Mail Removed)> wrote in message
news:ead7cu$21b6$(E-Mail Removed)...
> In article <(E-Mail Removed)>,
> Frankster <(E-Mail Removed)> wrote:
>
>>Yes, it is also important to note that "external" does not equate to
>>"public". Many networks use firewalls/routers totally inside their own
>>private address space. Each firewall/router still has an external and
>>internal interface.
>>
>>External and Internal addresses are present in every firewall/router
>>(separate two or more networks).
>>
>>Public and Private are not always present. Public equates to Internet
>>routable addresses and Private equates to Internet non-routable addresses.
>>
>>This is an area where correct terminilogy is everything.
>
> If terminology matters, then it would be better to write
> "RFC 1918 address" if that is what you mean by "Private."
> The phrases "Internet routable addresses" and "Internet non-routable
> addresses" are not well defined. There are many IP addresses that are
> not listed in RFC 1918, not in 127.0.0.0/8, and neither class-D nor
> class-E, but are not known to the community of default-free routers.
> Some of those IP addresses are unassigned, but others are assigned and
> routes to them could be advertised by BGP but are not.
>
> If you really care about terms, it is also worth noting that by official
> IETF dogma, all IP addresses are dynamically assigned. They differ
> only in how soon they are likely to be reassigned. Everyone is supposed
> to be prepared to renumber their networks sooner or later.
>
> Note also that whether an interface's IP address is configured with
> manual typing, reverse ARP, BOOTP, DHCP, PPP IPCP, or some other scheme
> is not necessarily related to how "dynamic" the address is, or likely
> it is to reassigned. Many computers with what most people consider
> "static" IP addresses are configured with DHCP or PPP IPCP.
>
>
> Vernon Schryver (E-Mail Removed)