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ISP change urgency!!!

we have a current link to an isp that hs 6 addresses on it, i.e. email, firewall, internet, ftp and edi. each one uses a different IP address.

i need to change all our services to a different wireless ISP link. we have 8 ip's on the new link. do all the ip addresses just be on the line or do i have to assign them ??? the new link is a wireless one, the old one is a dsl line where there was a router attached??

urgent, please help!!!
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Aaron Street
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if you are given a block of ip address 2 will always be used up..

first (usual first) will become you DSL router ipaddress and so the default gate way of all your PC,
and the last address is the network address (you dont assign this address usualy) and is used to send a broad cast to your network.

at some point there must be a router some where? even if tis not controled by you..

I think we nee d a bit more information before answering this..
how do you get the wireless. have the ISP installed a wireless router/accesspoint?

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ok sorry.the current setup is as follows

checkpoint firewall with 4 nics. two of these are the ISP links and default gateway is the dsl link., this is connected to a router and this router is connected to the dsl router

new setup is a  wireless link coming from antanne on roof straight into checkpoint firewall ( no router in betwen) i want change the default gateway to this link so i will have to change all the services that are currently coming in over the dsl link. like do the ip addresses that are given to you from your isp have to be entered somewhere i.e. would they be on the router in the dsl setup,

when i ping some of the IPs on the dsl link from outside then they respond, does that mean that they have a physical interface ?
i not usre i know what you are on about.

if you are using public ip address from the ISP on you internal PC's then you would expect them to respond to a ping unless you block it via settigns on the fire wall..

It  should be simply changing the network setting to the new setting and new default gate way. but like i say the way you have decribed it I not clear in my head how you have it set up ??

if ut ISP assigns you a block of public ip addresses. how do you assign all the ip addresses to your setup, can you just do NAT etc or does each IP have to setup on a physical interface???
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alan before i give yout the points. if i have two wan links and

my intenal IP of firewall is

if i have a switch and have these three interfaces connected to it, will i be able to ping the wan ip addresses from the firewall or will it not work ?
If your firewall (LAN is, then you should be able to ping  yyy.yyy.yyy.111.  Question is whether it would be routed via internet, or if it would stay on the hub because the other WAN device (cable/DSL interface) would answer.  Try and see.

You wouldn't necessarily be able to ping the .166 WAN IP from its LAN side.  Some firewalls will pass the traffic.  I have a SonicWall with recursive rules to do that.  Your mileage may vary.

it would depend what routing you have enabled..

by default you cant ping from one set of network address to another set. Unless you have a router that either through static routes or dynamic routes. will route the traffic between networks..

it would also depend what subnet masks you have on your networks..

the two IP address of you lan are external address. and the firewall has an internal address.

where is the router sitting ??
router is sitting behind the firewall. isp links are straigth into firewall and router is conencted to firewall