working to connect all the branches

Unanswered Question
Apr 30th, 2006

Dear Concerned,

We are trying to create the following environment for one of our clients.

There are 3 branches (with LAN) in the scenario;

• Head Office

• Branch Office A and

• Branch Office B

The Head Office and Branch office A is connected through ISP 1


The Head Office and Branch office B is connected through ISP 2

(both ISPs with same bandwidths)

ISP 1 and ISP 2 provide us with 2 (two) consecutive GATEWAY IP only for connectivity; but we are working to connect all the branches

without configuring with any routing commands in their (ISP) routers.

Can you come with any suggestion on this matter?

The IP list is as follows:

Head Office to ISP 1: IP address(From ISP 1 )

Gateway (ISP 1 end)

Head Office LAN:

Branch A to ISP 1:IP address ( From ISP 1)

Gateway (ISP1 end)

Branch A LAN:

Head Office to ISP 2: IP address ( From ISP 2) (Head Office end)


Branch B to ISP 2: IP address (From ISP2) (ISP2 end)


Branch B LAN:

It would be much appreciated if you could let us know your views.



I have this problem too.
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vladrac-ccna Sun, 04/30/2006 - 10:38

Hello Tushar,

I believe the term WAN provider will be better suited for these ISPs.

Ok...what kind of routing are you using in this network?

How can you reach from Head Office?

How can you reach from Head Office?


tushar@techvall... Tue, 05/02/2006 - 04:27

Dear Mr.Vlad

Thanks for your reply.Sorry i can't

ping from Head Office and from Head Office also?This is my mistake.I have a solution with GRE tunnel but without GRE ,is it possiable? any info would be appreciated.



mounir.mohamed Sun, 04/30/2006 - 20:45


I saw that all traffic coming from any branch toward other branch will go through the centeral point (Head Office) so i think if you using GRE tunnels between your branches to provide you with virtual any-to-any connectivity then run EIGRP/OSPF on the tunnels to exchange L3 informations will very nice solution for you

Please rate helpful posts

Best Regards,

Mounir Mohamed

tushar@techvall... Tue, 05/02/2006 - 04:00

Dear Mr.Monir

Thanks for your reply.I know this techonology but i would to solved this without GRE .Is it possiable?

I appreciate you taking the time and explaining.pls i'm serious about it and i want help .



vladrac-ccna Tue, 05/02/2006 - 08:55

Hello Tushar,

Just curious, how did you setup this tunnels?

could you paste here a sample of:

show ip route on the Head office?


tushar@techvall... Tue, 05/02/2006 - 22:52

Dear Mr.Vlad

We do not yet set up any kind of tunneling (i.e. GRE tunneling)) in between our client branches.

The thing is, we are trying to find an alternate solution for this matter besides tunneling.

Can you please suggest any other possible way to this?

Right now, we’ve established connectivity between Head Office and Branch Office A because it’s connected through the same ISP (ISP1); but we’re unable to connect Branch Office B (as it’s connected through a different ISP (ISP2).

The IP list is given below:


interface f0/0: ip address (connecting ISP1)

gateway(ISP1): ip address

interface s0/0: ip address (connecting ISP2)

gateway(ISP2): ip address

interface f0/1: ip address (Head Office LAN)

for ISP1

ip route

ip route

for ISP2

ip route

ip route




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