Hi again !!

Thank You for reply, I really tried to find a solution for this scenario, but it seems that I had no luck this time :( I hope that You can figure it out. I was thinking about static arp table, but not useful at all because this is used to ensure that user receives the same ip from dhcp each time it ask for it, but this will not pervent user to type another ip address manually and connect to the network.

Thank You I am waiting for some answer and I hope that You can find a solution.

Best regards

One way could be this (I can't test that yet).

Configure the IP DSLAM to map each PVC that need a static address in a separate vlan.

Under the subinterface, configure a private address/mask, that is ok as long doesn';t overlap with others.

Then configure as many static routes as necessary with mask /32 for the static address, pointing each one to the corresponding subinterface.

Could I ask You for one "sample example config" that is working ?

I`ll be out of the office for 1 hour, but than I am back !!

Thank You very much for helping !!!!

I really need to fix this isue.

Best regards

hmm, well let me think little about it, so I`ll let You know my understanding...

Looks very interesting solution......

Thank You very much !!!!

Best regards

This one should work by virtue of proxy arp. The PC sends ARP for gateway address, and even if this address is not the one of the interface receiving ARP, router will reply with a MAC address.

Thanks for the nice rating and let us know how it goes!

You`re welcome !!!

Well hope that I have right understanding now.

Let say we have one sub-interface:

int fa/0.010

description dsl_cust

ensapsulation dot1q 10

ip address 80.80.80.1 255.255.255.0

Than we configure the IPDSLAM for example,

we configure switch port number 1 on the

IPDSLAM as a member of the VLAN 10, but hmm

I am still little confused here.. because this dsl user needs to use the ip 80.80.80.1

as the gateway and he can use 80.80.80.2 as

his static ip address. But I still don`t understand how I can (fix) this ip, so he can`t use for example 80.80.80.3 og .4 not just .2

I am really trying to understand but it is not that easy.

Thank You for helping !! any better explanation using config maybe ?

Best regards

Well for 20 min ago I asked one of my old friends to test something for me. He is connected to the ISP which assigns static ip addresses for its customers.

Let`s say this is the ip address my friend got from his ISP:

ip address 80.50.50.3

subnetmask: 255.255.255.0

gateway: 80.50.50.1

And he is only able to use ip address 80.50.50.3 and not another ip addresses, even if this is a big subnet. Another customer got 80.50.50.4 and both of these customers uses the same gateway. But they can`t use another ip address than one ISP assigned to them.

My friend have Cisco ASA 5505 and he NAT`s to his internal LAN, so his lan ip of the ASA is 10.10.10.1 255.255.255.0.

And than I asked him to trace google.com

so after the trace was successfull:

As first HOP he got the ip address

1 10 ms 7 ms 6 ms 10.227.2.1

And if You see this ip address is not on his network, this is ip address from IPDSLAM I think ?? and why he receives this ip address, because as first hop he should get the ip address 80.50.50.1, because this is his GATEWAY he got from his ISP and this ip is used in the default route on his ASA, but not instead of ip 80.50.50.1 he gots this ip as first hop 10.227.2.1

So they must use one or another router on the PSTN which is connected to IPDSLAM or this is ip of the IP DSLAM.

Do You understand this scenario ??? maybe this will give You idea how to explain it to me ??

Thank You !!!!

I AM REALLY SORY for long post, but I like to describe every detail, so You understand what I mean.

Best regards

James,

You have observed in act, what I was suggesting you to try.

He gets an "off-subnet" first hop address because the router interface doesn't have the address configured as GW on the ASA. Instead that interface has a private address picked as ISP likes.

But due to proxy-arp, or call it router magic, no other address outside the static route will work on that vlan. You can also add more addresses to a customer, if you want.

Good luck!

Well I`ll try it tomorrow, and I`ll let You know !!

Thank You again !!

Best regards

Hello again !!

Well I really tried but no success, do You have any possibilities to create a short sample how the config exactly should look like ?? on the BRAS (Router) ? where the IPDSLAM is connected to.

Thank You for helping !!!

I`ll rate the answer !! hope You`ll create the short sample.

I`ll really appreciate Your help !!

Best regards

James

this is not possible without the use of an radius assigned pool. which will need pppoe or pppoa.

Steve

Well, than how this ISP I was talking about fixed these issues ? They are just giving their customers "static ip address" "subnetmask" and "gateway" så than they are on the network, no PPPoA and no PPPoE. So this is 100% possible, but I just need one example from someone who did this before.

Thank You

Best regards