The global (outside) 1 interface will activate PAT - Port address translation. I supose you had previously configured NAT.
Yes this will solve your outbound address limitation.
The isakmp nat-transversal is not for outbound VPN connection issues it is for inbound VPN issues.
isakmp nat-traversal
Network Address Translation (NAT), including Port Address Translation (PAT), is used in many networks where IPSec is also used, but there are a number of incompatibilities that prevent IPSec packets from successfully traversing NAT devices. NAT traversal enables ESP packets to pass through one or more NAT devices.
The firewall supports NAT traversal as described by Version 2 and Version 3 of the IETF "UDP Encapsulation of IPsec Packets" draft, available at http://www.ietf.org/html.charters/ipsec-charter.html, and NAT traversal is supported for both dynamic and static crypto maps. NAT traversal is disabled by default on the firewall.
To enable NAT traversal, check that ISAKMP is enabled (you can enable it with the isakmp enable if_name command) and then use the isakmp nat-traversal [natkeepalive] command. (This command appears in the configuration if both ISAKMP is enabled and NAT traversal is enabled.) If you have enabled NAT traversal, you can disable it with the no isakmp nat-traversal command. Valid values for natkeepalive are from 10 to 3600 seconds. The default is 20 seconds.
See: http://www.cisco.com/en/US/products/sw/secursw/ps2120/products_command_reference_chapter09186a00801727a9.html#wp1027312
You probably mean the fixup.
The fixup protocol esp-ike command enables PAT for Encapsulating Security Payload (ESP), single tunnel.
The fixup protocol esp-ike command is disabled by default. If a fixup protocol esp-ike command is issued, the fixup is turned on, and the firewall preserves the source port of the Internet Key Exchange (IKE) and creates a PAT translation for ESP traffic. Additionally, if the esp-ike fixup is on, ISAKMP cannot be turned on any interface.
See:http://www.cisco.com/en/US/products/sw/secursw/ps2120/products_command_reference_chapter09186a00801727a8.html#wp1067379
All refernce is for PIX OS 6.3.4 !
sincerely
Patrick
