Multiple Public IP Addresses.

[dataconn]

Hello everyone

I have a new connection about to go live on 25th March - it has a range of fixed IP addresses.  With other ISP's in the past, they seemed to allocate a single IP address and then route the range of IP's down to that IP.  But the IP address range allocated to me in the welcome email seem to be just one range, and not have a single IP as well.   I don't really mind how things are implemented technically, all I actually need to know is how to program a router such as a Netgear DG834 to use this public IP range.

Any help in advance would be much appreciated.

[Sebby]

I've never had any experience of blocks of IPs myself, but I'm sure someone here will be able to give you some guidance.

[Simon]

Hi dataconn, and 

I'm afraid I can't help you with this either, but if no one here has experience of this, a quick call to IDNet in the morning will soon clarify things for you.

[Sebby]

Good point, Simon. As it happens, the Netgear DG834 is one of the routers that IDNet sell themselves, so I'm sure they'll be familiar with its setup.

[Rik]

Hi Dataconn and welcome to the forum.

I've never needed a block of addresses so have no experience to offer. My best advice has to be to give IDNet a ring, 0800 0267237. You'll find yourself talking to someone who knows exactly what you need to d and, as Sebby says, IDNet supply these routers so they will be familiar with what's needed.

[dataconn]

Ok, well it turns out that ID Net don't give a single IP that the range of IP's is routed down.  This is not a bad thing, just different to how I've done it in the past.  Basically plug your router in and set it up as normal.... then in the LAN settings put your IP range (starting from the 3rd one up in the range -1st is dead, 2nd goes to router, 3rd onwards are useful and can be allocated to servers / phones etc).  This would be suitable on a netgear DG834 for instance...  If you wanted to run NAT from one of the IP's you would have to connect an additional router (of the Ethernet WAN type) or you can use a more powerful router such certain Cisco's which can handle both public ip's and NAT at the same time.

If anyone wants to know more then please just ask.

[Sebby]

Thanks for letting us know.

[plugwash]

what does the router say it's internet side IP is in the status pages?

[Adam]

what does the router say it's internet side IP is in the status pages?

The router will most likely take the first usable IP address of the allocated range, though it is configurable.

[plugwash]

I said internet side not lan side.

I'm guessing that idnet have allocated a single ip for the internet side of the router and just didn't bother to include it in the email because they didn't think it was very relavent.

[Adam]

1st is dead, 2nd goes to router, 3rd onwards are useful and can be allocated to servers / phones etc).

Both the first and the last IP addresses in the range are not usable, the first is the network address and last the broadcast address.

If you wanted to run NAT from one of the IP's you would have to connect an additional router (of the Ethernet WAN type) or you can use a more powerful router such certain Cisco's which can handle both public ip's and NAT at the same time.

The 2700HGV supports the use of NAT and public IP allocation in parallel, though it requires some tweaking to get working correctly and is fairly inflexible configuration wise.

[Adam]

I said internet side not lan side.

If using a router like the DG834G with public IP allocation then the public router IP and the LAN IP range will be the same, unless NAT is implemented which would negate the need for multiple IP public addresses.

I'm guessing that idnet have allocated a single ip for the internet side of the router and just didn't bother to include it in the email because they didn't think it was very relavent.

The public router IP will come out of the allocated public IP range, it is not a separate dedicated IP.

[Colin Burns]

hmmm that rings a big bell CCNA   

[Dangerjunkie]

Other ways to deal with this would be:

1) Get an Ethernet modem like the Draytek Vigor 100 or possibly the ADSL Nation X3. Connect it to an 8-port Ethernet switch. connect the WAN sides of up to 6 cable NAT routers, like the Netgear RP614 or WGR614, to the switch. You then manually set the IP address of each router to one of the available public IPs (make sure they are static.) You will then have up to 6 independent NATed networks, each with 1 public address.

2) Get an Ethernet modem like the Draytek Vigor 100 or possibly the ADSL Nation X3. Get a cr*ppy old PC (I use a 266MHz Pentium II with 256MB RAM) , put 4 network cards in it (I recommend cards based on the Realtek RTL8139 chip. These should be available tor less than £5 each.) Install a dedicated firewall on it (I use IPCop http://www.ipcop.org but you could try something like Smoothwall Express http://www.smoothwall.org/ instead.) Connect the Red (WAN) interface to the modem you then have a Green LAN (for your PCs), a yellow LAN (DMZ for servers) and a Blue LAN for your wireless to protect your computers in case your wireless gets hacked. You can then route any of the ports or port ranges on any of the external IP addresses to any computer on your LANs. You will then have industrial-strength firewall protection

Cheers,
Paul.

[somanyholes]

This is how it normally works.

ip range

91.135.0.96 - 91.135.0.103

this is a 91.135.0.96/29 so the subnet is 255.255.255.248

91.135.0.96 network address
91.135.0.97 1st usable could be router address
91.135.0.98 2nd usable
91.135.0.99 3rd usable
91.135.0.100 4th usable
91.135.0.101 5th usable
91.135.0.102 6th usable
91.135.0.103 broadcast address

You normally get 6 usable public ip's that you can use for whatever you want, e.g. mail server webserver etc, i presume you are a business customer.

[plugwash]

The public router IP will come out of the allocated public IP range, it is not a separate dedicated IP.

The routers lan side IP will sure. but unless there is something weired going on the router should also have a wan side IP.

[somanyholes]

but unless there is something weired going on the router should also have a wan side IP.

this is exactly what adam was saying in

The public router IP will come out of the allocated public IP range, it is not a separate dedicated IP.