Cisco VPN Client
Cisco VPN Client
How to enable a Cisco Systems virtual private network (VPN) client computer using the IPSec protocol, on the internal network, to connect to an external Cisco VPN Concentrator using the "transparent tunneling" feature through some firewalls
In most cases, IPSec VPN traffic does not pass through major firewalls, However, some firewalls with the latest software/firmware updates, uses "transparent tunneling" that uses User Datagram Protocol (UDP) ports 500, 4500, and 10000 to communicate securely between VPN clients and Firewalls.
To provide support for this configuration, you would need to create the following protocol definitions:
Note The client computer must be configured as a SecureNat client, if supported.
Port number: 500
Protocol type: UDP
Direction: Send Receive
Port number: 4500
Protocol type: UDP
Direction: Send Receive
Port number: 10000
Protocol type: UDP
Direction: Send Receive
By creating these protocol definitions, you enable the SecureNat client to connect to the Cisco VPN server through Firewalls as all traffic is passed as UDP traffic.
According to the Cisco Transparent tunneling technology, this traffic can traverse Network Address Translation (NAT) firewalls.
Note: You must make sure that your Access Policy permits these three custom protocols.
Client download
/tools/cisco/vpnclient_5.zip - vpnclient-win-msi-5.0.06.0160-k9