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Problem with 5 static ip block using PPPoE connection

Last Modified: 2013-12-21
Ok, here is the situation...i currently have a linksys router with dd-wrt v24 with the DSL modem in bridge mode with the router providing the pppoe credentials...i ordered a block of 5 ip addresses from Windstream...when i went to assign the static ip addresses to the router i found that it isn't nativley supported so i sped up my plans to run a server with ISA 2004...i realize that may seem like over kill but i had the server and the licenses so it was no biggie, anyway...i go to setup the WAN side and come to find that the default gateway that the router has, isn't even on the same subnet as my ip block...and the netmask is 4 octets of 255...so i call windstream and ask them about it...they say that the subnet mask and gateway are correct its just how they do it and that any request to an ip address in my block is automatically routed to my pppoe credentials, so in theory right now any thing i point to those 5 ip addresses should be answered by my router already which i assure you isn't the case (if i am wrong about that please correct me)...so i tell the guy this and he says i need to assign the public ip address to a device(he kind of worded it to sound like i had to add the route somewhere) so that it knows to listen...here is where i get confused, if all 5 ip addresses automatically point to my PPPoE credentials then how do i assign my other 4 ip addresses to a device (i feel kinda like this is confusing so i apologize but any help is appreciated)how can i assign the other for addresses to an interface that is set to get the public ip address by DHCP...ideally id have the modem handle the pppoe info and assign the block of 5 ip addresses to the WAN interface to the ISA firewall so i can point different public domain names to come in through different ip addresses so i can monitor that stuff and lock it down really well...it feels like im the one in the wrong here, i don't know why but i do...basically i need any help i can get, even if it is just what question to ask windstream...also i would prefer not to have to do a 1-to-1 nat if possible


ok im leaving all of that previous info for the sake of history but here is something i dug doing research on my own


so according to this it is no question why i currently can only use 1 of my static ip addresses...i know i am running dd-wrt but it looks as though, it can't even do what i want only open-wrt can...i have almost no linux experience so i can't really use that method...so do i need to snatch up a cisco router and set it up to handle the PPPoE info and just forward everything to the public interface of tyhe isa firewall...im having a little problem wrapping my brain around this so any help would be appreciated

Watch Question

I'm guessing you will be setting up the network like this:
Internet----OutsideIP[Linksys]InsideIP----OutsideIP[ISA]InsideIP----Local LAN

If this is the case, then assign the "extra" block from the ISP to the inside of your Linksys router (used in routing mode, not bridged), and the outside of your ISA server (use one address within the subnet on each device).  The ISA server inside interface would then be assigned with a private address in the range you select, and the additional addresses can be used in the ISA server for whatever NAT translations you need.

Does this help?


Well with all my research i have found this all to be very confusing...but here is where im at...i currently have a modem being shipped to me (it was owed to me whenever i signed up for server, i just never got it) that should be capable of providing the pppoe credentials and passing along the public ip addresses to the wan interface of my ISA server...i won't really know how succesdsful i am until it comes in which sucks but i am confident...one thing i did have a questions about which is just one of the many things about this sticky ip addessing i don't get...currently on my dd-wrt router, this is my WAN ip config

IP Address98.***.***.185  
Subnet Mask255.255.255.255

how in the hell does that work? that gateway is on a completely different subnet...how am i to get windows server 2003 to like that, or do i ignore that and just enter the info like i have it in the test environment

ip 98.***.***.185
GW 98.***.***.190

this is what windstream sent me in my official document with my account info

IP Block: 98.***.***.184/29
Router IP: (i find this the most confusing)
Useable IP's: 98.***.***.185-190

oh and i just read this on the service agreement
Please Note Regarding the SpeedStream 5200/4200 Modem / Router. The 5200/4200 is a bridge/router. Out of the box, although the LAN port has an IP number ( it will function as a bridge to the router/firewall connected behind it. If the 5200/4200 gets programmed with your DSL login and password, either via the GUI interface or the Setup CD, it will then be in router mode. In this mode, if you are planning on using another router/firewall behind the 5200/4200, you will not get a Public IP address on the WAN port of your device. The 5200/4200 is a low end Residential Gateway type of router an as such it must do address translation (NAT) to a private IP subnet on its LAN. Also, as it is only a Residential Gateway class device you will only be able to use the Public IP address of the WAN port for Port Forwarding, etc. You will not be able to utilize any additional Static IP addresses. If you need the use of more than 1 Public IP address the 5200/4200 must be used in bridge mode with a Business Class router/firewall behind it that is capable of doing a PPPOE login, or you must use a Business Class router with an internal ADSL port such as the Cisco 837 or the Adtran NetVanta 340/344. In order to get the 5200/4200 back to factory default (bridge mode) it must be reset via the reset button accessed through the small hole in the bottom of the 5200 or the back of the 4200. With the 5200/4200 powered on depress the reset button with a paper clip and hold for ~ 4 to 6 seconds, until the Power light flashes red/green on the 5200 or green only on the 4200, and release. Do not depress the button for more than 10 seconds or the factory reset will be ignored

so that modem they are sending may not help at all...does this help explain what i am trying to figure out any better

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