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Bandwidth Goes down after enabling Ipsec tunneling


I was trying to enable Ipsec tunneling in one customer place.the Network setup is like this.

the customer is using cisco 1761 Router in both which has 2 serial interfaces &ve connected the same using a leased line connectivity .this line is using for failover meanwhile we have two installed a Micro Red modem in both end to establish a wireless connectivity with gives 6 mbps output (this link is working as primary link).but this modem does nt have a V.35 interfce ,only Rj45 interface is I terminated the same to a Dlink unamaged switch ,ethernet interface of the router also teminated to the same switch & Gateway of all the internal clients is pointing to routers ethernet interface.

Here the problem is like this, as financial organisation ,the client needs enable Ipsec tunneling in wireless link also even though it have an in built security mechanisum .So after enabling the ipsec tunneling in router the Bandwidth goes down to 1 mbps.

Thsi time Cpu utilization goes upto 90% also.

So let me please know is it problem of interface termination ? or router load issue .Please give a solution for the same ASAP

Thanks & regards

Praveen sg

Hall of Fame Super Gold

Re: Bandwidth Goes down after enabling Ipsec tunneling


the 1761 does not have hardware-based IPsec module so dos it in software. Because of this, the limited performances. You can use a router like 871 or bigger, or an ASA PIX for better performances, as these have hardware-based VPN.

On the 1760, you can only try configuring the lightest cyphering that is DES, hoping will alleviate the CPU a little.

Hall of Fame Super Gold

Re: Bandwidth Goes down after enabling Ipsec tunneling


I gave incorrect information here so a correction is due. The 1760 can indeed have an hardware accelerated VPN module, MOD1700-VPN.

The documentation report performance "up to T1/E1 speeds". Hope this can help.