Difference between internal and public IP address?

[AstroBenny]

So I'm trying to get some semi-decent networking knowledge under my belt...I understand that your ISP assigns your router a public IP address and then the router assigns internal IP addresses to all the devices connected to the router..

What I don't really understand is, when reading this article, is it referring to the public IP address of the router or the internal IP address of the device that is connected to the internet?

http://www.bleepingcomputer.com/tutorials/ip-addresses-explained/
 

I'm currently in the process of moving to a new ISP who offers me a static IP address which can supposedly be useful for setting up game servers etc.

But does a static IP mean my public IP will never change even if I restart my router or does it mean the internal IP addresses on the network will never change for each device connected?

And this has got me thinking...If the IP address doesn't change, what do I do when I get DOSed when playing some games on Xbox? Will I have to call the ISP and get them to change the IP?

Cheers. Enjoy what's left of your weekend

[Altecice]

But does a static IP mean my public IP will never change? - Yes.

 

Does it mean the internal IP addresses on the network will never change for each device connected? - YES it wont have any impact on your internal IP subnet.

 

Its up to your ISP to decide how to deal with your last request.

----

In its very basic form, some people created a standard that said said that some IP ranges cannot be routed publicly and this standard has been adopted by all router manufactures. Think of an external IP as a single IP that you lease (dont own) and YOUR private IP is one you own and have full control over but cannot be routed out into the internet.

 

 

 

 

 

 

[thekeemo]

internal is the IP address that is specific to each device on a network and is used for internal communication.

The "normal" IP address applies to ALL devices on a network.

Ports are forwarded or triggered to certain local IP address via a modem allowing you to access your information.

[vanished]

7 minutes ago, AstroBenny said:

... does it mean the internal IP addresses on the network will never change for each device connected?

Your router assigns the internal IPs for each device.  I've had routers that will start from 1 and count up, changing them often to try and keep all the numbers sequential (usually causing problems in the process) and routers that seem to pick a random number from 1 to 255 for each device and then stick with it for life, which is nice, so it depends on the device.  I believe you can also just manually assign them too, if you don't mind the extra effort.

[Lurick]

A private address is something in the range of:

10.0.0.0/8

172.16.0.0/16

192.168.0.0/16

These addresses are not routable over the public internet and what happens is the router or modem will perform what is called NAT or PAT. NAT translates an internal address to an external public address and when it comes back it gets routed to the right computer on the network and all of this is done on the router which keeps a table of the mapping. When you have a single address or just a couple public addresses you do something called PAT or Port Address Translation (aka NAT overload) where multiple internal addresses can use the same external address and are translated externally but a port is used instead for the return traffic. This is a very basic explanation and I can dive into much more detail if you want but just gives an idea of whats happening.

[JefferyD90]

8 minutes ago, AstroBenny said:

So I'm trying to get some semi-decent networking knowledge under my belt...I understand that your ISP assigns your router a public IP address and then the router assigns internal IP addresses to all the devices connected to the router..

What I don't really understand is, when reading this article, is it referring to the public IP address of the router or the internal IP address of the device that is connected to the internet?

http://www.bleepingcomputer.com/tutorials/ip-addresses-explained/
 

I'm currently in the process of moving to a new ISP who offers me a static IP address which can supposedly be useful for setting up game servers etc.

But does a static IP mean my public IP will never change even if I restart my router or does it mean the internal IP addresses on the network will never change for each device connected?

And this has got me thinking...If the IP address doesn't change, what do I do when I get DOSed when playing some games on Xbox? Will I have to call the ISP and get them to change the IP?

Cheers. Enjoy what's left of your weekend

Wrong, your ISP assigns your MODEM a IP address.  Then, if you have a router connected to your modem, it will ROUTE  (thus the name router) the data on that traffic to the appropriate devices connected to the router, usually via a networking switch (which gives each device on the switch its own IP address to use ON THAT SWITCH ONLY).

[Lurick]

2 minutes ago, JefferyD90 said:

Wrong, your ISP assigns your MODEM a IP address.  Then, if you have a router connected to your modem, it will ROUTE  (thus the name router) the data on that traffic to the appropriate devices connected to the router, usually via a networking switch (which gives each device on the switch its own IP address to use ON THAT SWITCH ONLY).

That is incorrect, unless you have a L3 switch with DHCP pools configured on it it will not hand out IP addresses or even care about the addressing. So long as all the switches in the network are connected in some form or fashion and all the computers connected are in the same subnet then you can have hundreds of computers connected to different switches still talk with one another.

[JefferyD90]

2 minutes ago, Lurick said:

That is incorrect, unless you have a L3 switch with DHCP pools configured on it it will not hand out IP addresses or even care about the addressing. So long as all the switches in the network are connected in some form or fashion and all the computers connected are in the same subnet then you can have hundreds of computers connected to different switches still talk with one another.

You're correct, but this guy is starting out.  Don't you think he needs to grasp the concept all of the hardware inside a "standard" router before you start throwing things like subnets into it?

[Lurick]

Just now, JefferyD90 said:

You're correct, but this guy is starting out.  Don't you think he needs to grasp the concept all of the hardware inside a "standard" router before you start throwing things like subnets into it?

Neva! Subnet all the things, route with all the protocols!

 

Yah, baby steps are important when starting out.

[leadeater]

3 hours ago, JefferyD90 said:

Wrong, your ISP assigns your MODEM a IP address.  Then, if you have a router connected to your modem, it will ROUTE  (thus the name router) the data on that traffic to the appropriate devices connected to the router, usually via a networking switch (which gives each device on the switch its own IP address to use ON THAT SWITCH ONLY).

Not quite correct, modems do not have IP addresses and are responsible only for converting digital data to analogue and vice versa. This is the purest and most correct definition of a modem and is where it's name is derived from  modem (modulator-demodulator). Modems operate in layer 1/2 of the OSI model which is below IP addressing which is layer 3.

 

What is more commonly found in homes is an All-in-One (AIO) device which is a modem, router and switch in a single device. The router portion of this device is the one that gets the public IP. When you put one of these AIO devices in bridge mode like I do to my Fortigate firewall it is operating in modem only mode and my firewall NIC gets the public IP using PPPoE/PPPoA passthrough.

 

Also not all internet connections require a modem. Some are native ethernet or a fibre protocol so are digital through the entire path so do not require a modem.

 

When starting out in networking it is important to know exactly what each device actually is and does so you don't learn false information which will trip you up later down the line.

[JefferyD90]

On ‎5‎/‎2‎/‎2016 at 8:54 PM, leadeater said:

Not quite correct, modems do not have IP addresses and are responsible only for converting digital data to analogue and vice versa. This is the purest and most correct definition of a modem and is where it's name is derived from  modem (modulator-demodulator). Modems operate in layer 1/2 of the OSI model which is below IP addressing which is layer 3.

 

What is more commonly found in homes is an All-in-One (AIO) device which is a modem, router and switch in a single device. The router portion of this device is the one that gets the public IP. When you put one of these AIO devices in bridge mode like I do to my Fortigate firewall it is operating in modem only mode and my firewall NIC gets the public IP using PPPoE/PPPoA passthrough.

 

Also not all internet connections require a modem. Some are native ethernet or a fibre protocol so are digital through the entire path so do not require a modem.

 

When starting out in networking it is important to know exactly what each device actually is and does so you don't learn false information which will trip you up later down the line.

ewww, do people actually use Modem/Router Combos?  I know grandma and everyone like that does... but I'm surprised that this many people on the forum use combo units.  That's just nasty.

[leadeater]

1 minute ago, JefferyD90 said:

ewww, do people actually use Modem/Router Combos?  I know grandma and everyone like that does... but I'm surprised that this many people on the forum use combo units.  That's just nasty.

Extremely common for countries that use ADSL/VDSL type broadband connections. People actually using dedicated routers etc is a minority, people just use what ever their ISP gives them or just buy a more $$$ of the exact same thing totally unaware or unable to use better equipment.

[vanished]

1 minute ago, leadeater said:

Extremely common for countries that use ADSL/VDSL type broadband connections. People actually using dedicated routers etc is a minority, people just use what ever their ISP gives them or just buy a more $$$ of the exact same thing totally unaware or unable to use better equipment.

unfortunate though...

[JefferyD90]

1 minute ago, leadeater said:

Extremely common for countries that use ADSL/VDSL type broadband connections. People actually using dedicated routers etc is a minority, people just use what ever their ISP gives them or just buy a more $$$ of the exact same thing totally unaware or unable to use better equipment.

I knew that "normal" people did.  But I figured that WE THE MASTER PC RACE would know better...

[matrix07012]

On 1. 5. 2016 at 11:00 PM, AstroBenny said:

And this has got me thinking...If the IP address doesn't change, what do I do when I get DOSed when playing some games on Xbox? Will I have to call the ISP and get them to change the IP?

Stop playing Call of Duty with 10 year olds then. Kappa

Edited May 3, 2016 by matrix07012
fixed grammar

[Lurick]

On 5/1/2016 at 5:00 PM, AstroBenny said:

And this has got me thinking...If the IP address doesn't change, what do I do when I get DOSed when playing some games on Xbox? Will I have to call the ISP and get them to change the IP?

Cheers. Enjoy what's left of your weekend

Depending on your ISP and how long the DHCP address is bound to the MAC address, most likely you will.

[AstroBenny]

5 hours ago, matrix07012 said:

Stop playing Call of Duty with 10 year olds than. Kappa

#rekt

 

BTW it's then, not than.

[vanished]

1 hour ago, AstroBenny said:

#rekt

 

BTW it's then, not than.

Funny, most people use it wrong the other way around

[matrix07012]

2 hours ago, AstroBenny said:

#rekt

 

BTW it's then, not than.

Thanks