4 IP Block /30
- Thread starter eXor
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Deleted member 64478
Deleted member 64478
4 IP Block /30
A 4 IP block provides 2 usable IP addresses to the customer (1 for the router and 1 for servers, PC, etc.). The customer therefore needs to justify why they require an additional 1 static IP address.
1 for the broadcast and one for the network address and 2 usable WAN addresses.
I said yes before but changed it to no because you have a modem in the pic, which I just relised. Only certain routers can handle multi block addresses.
A 4 IP block provides 2 usable IP addresses to the customer (1 for the router and 1 for servers, PC, etc.). The customer therefore needs to justify why they require an additional 1 static IP address.
1 for the broadcast and one for the network address and 2 usable WAN addresses.
eXor" said:
I said yes before but changed it to no because you have a modem in the pic, which I just relised. Only certain routers can handle multi block addresses.
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Huh? The posts here are complete tosh, he doesn't have a router at all so he still has two usable IP ranges.
Yes both clients would have their own IP provided you set them up that way using only the modem / switch layout.
With a /30 subnet you would have 4 ip addresses, but only 2 usable (the other two being one used for network address, one used for broadcast)
IF however you implemented a router instead of a switch / modem setup to connect the clients to the WAN link then the router would take one of those useable IPs those leaving you only one left to potentially supply two computers. You would need to enable NAT for one of them on the router, and have the other have its own unique IP from the /30 you have been provided.. if this can be done, would depend on the router.
Yes both clients would have their own IP provided you set them up that way using only the modem / switch layout.
With a /30 subnet you would have 4 ip addresses, but only 2 usable (the other two being one used for network address, one used for broadcast)
IF however you implemented a router instead of a switch / modem setup to connect the clients to the WAN link then the router would take one of those useable IPs those leaving you only one left to potentially supply two computers. You would need to enable NAT for one of them on the router, and have the other have its own unique IP from the /30 you have been provided.. if this can be done, would depend on the router.
Deleted member 64478
Deleted member 64478
What you on about? Without a router he cant use 2 wan addresses only 1. Like you said "would depend on the router" thats what I said in my post so how is it completly tosh?
I might be silly but I can't see how the modem in that picture would allow two IP addresses to be configured on the clients.
Not many IP services support bridged networking for the distribution of IP addresses, at least not many that I have used.
Not many IP services support bridged networking for the distribution of IP addresses, at least not many that I have used.
Man of Honour
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Actually that makes no sense, all public IPs have to be register with ripe whether as part of a larger block or the individual ranges. If you mean RIPE don't need to approve individual allocations then no they don't but depending on the size of the ISP they'll be able to register far bigger allocations without approval. We can assign a /23 to any customer for instance...
Deleted member 64478
Deleted member 64478
That information was quoted from a site. I will remove it.
Man of Honour
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Ah probably thats their own policy, odd though, a /30 is generally pretty useless, if an ISP is prepared to offer a /30, then why not a /29? It's not like IPs actually cost anything to them...
Open your subnet up to enable you to make use of the network/broadcast address.
For example with a /29 range, I can set the subnet on the router to /24 instead. That way I can use all 8 addresses. The only drawback being you can't communicate with the other hosts on the internet in the same range.
For example with a /29 range, I can set the subnet on the router to /24 instead. That way I can use all 8 addresses. The only drawback being you can't communicate with the other hosts on the internet in the same range.
Sounds like Plusnet's policy - they're extremely anal about IP assignments.
Mind posting your setup and hardware? I'm getting nowhere here.
E.g. with a /30 (subnet 255.255.255.252)
81.5.100.4 - network (non-usable)
81.5.100.5 - router (automatically assigned by Eclipse)
81.5.100.6 - computer
81.5.100.7 - broadcast (non-usable)
To make use of the other addresses simply extend the subnet on your router to include them, a /28 would work for example (255.255.255.240).
If you're unfortunate enough to be stuck at the start or end of a network range then you're out of luck and will only be use one extra address instead of two.
PS. Eclipse will give you an 8 IP block if you ask.
My block is :
IP Address(es) 91.xxx.xxx.25 > 91.xxx.xxx.26 2 fixed usable addresses ( /30 )
Subnet Mask 255.255.255.252
Gateway 82.xxx.xxx.xx ( sometimes 212.xxx.xx.xx )
When I tracert a public IP, the first hop is 192.168.2.1 ( modem local ip ) so it seems as if the half bridge implementation is not as transparent as it can be. Which modem/router do you have?
You a need a device that is able to do full routing mode, i.e. with public IPs, not NAT.
I have the 3Com OfficeConnect 812, and it's able to share the assigned public IP on the WAN and LAN interfaces (which saves using up another address).
If you were to use some sort of PPPoATM to PPPoE device like this you could use it in conjuction with a Linux machine to do the routing. Though I'm not sure if you'd run into trouble trying to change the subnet value. In theory this would give you access to all four IPs.
I have the 3Com OfficeConnect 812, and it's able to share the assigned public IP on the WAN and LAN interfaces (which saves using up another address).
If you were to use some sort of PPPoATM to PPPoE device like this you could use it in conjuction with a Linux machine to do the routing. Though I'm not sure if you'd run into trouble trying to change the subnet value. In theory this would give you access to all four IPs.