<div>
What you are trying to accomplish is DMVPN, or dynamic multipoint VPN. WE have a couple of these setup and they work great, only downside is they only work on routers, not on the PIX or ASA. <br />
<br />
Here is another link that is more specific to your question. <br />
<br />
<a href="http://www.cisco.com/en/US/partner/products/ps6120/products_configuration_example09186a00805c5ad9.shtml" rel="ugc">http://www.cisco.com/en/US/partner/products/ps6120/products_configuration_example09186a00805c5ad9.shtml</a>
</div>


What you are trying to accomplish is DMVPN, or dynamic multipoint VPN. WE have a couple of these setup and they work great, only downside is they only work on routers, not on the PIX or ASA.

Here is another link that is more specific to your question.

http://www.cisco.com/en/US/partner/products/ps6120/products_configuration_example09186a00805c5ad9.shtml [http://www.cisco.com/en/US/partner/products/ps6120/products_configuration_example09186a00805c5ad9.shtml]

<div>
<div class="content wysiwyg-content">
We have a Cisco ASA 5505 at a site with a static IP address and would like to be able to establish site-to-site VPN connections from PIX 501 firewalls on dynamic IP addresses. &nbsp;When you set up a site-to-site connection, you're only allowed to enter an IP address. &nbsp;If we use a dynamic IP address and it changes, the VPN will be broken. &nbsp;Is there a way to set the ASA 5505 to accept incoming site-to-site VPN connections without having to explicitly specify the IP it's coming from? 
</div>
</div>


We have a Cisco ASA 5505 at a site with a static IP address and would like to be able to establish site-to-site VPN connections from PIX 501 firewalls on dynamic IP addresses.  When you set up a site-to-site connection, you're only allowed to enter an IP address.  If we use a dynamic IP address and it changes, the VPN will be broken.  Is there a way to set the ASA 5505 to accept incoming site-to-site VPN connections without having to explicitly specify the IP it's coming from? 

Cisco VPN Connections between static and dynamic IP's

Software firewalls, also known as host-based firewalls, provide a layer of software on one host that controls network traffic in and out of that single machine. Most operating systems now include firewall software, but many available software firewalls include central distribution, antivirus systems and disaster recovery.

Software Firewalls

Cisco PIX is a dedicated hardware firewall appliance; the Cisco Adaptive Security Appliance (ASA) is a firewall and anti-malware security appliance that provides unified threat management and protection the PIX does not. Other Cisco devices and systems include routers, switches, storage networking, wireless and the software and hardware for PIX Firewall Manager (PFM), PIX Device Manager (PDM) and Adaptive Security Device Manager (ASDM).