2010年5月10日 · For IPSec VPN, the following ports are to be used: Phase 1: UDP/500. Phase 2: UDP/4500.

2011年5月23日 · NAT-T encapsulates the Quick Mode (IPsec Phase 2) exchange inside UDP 4500 as well. After Quick Mode completes data that gets encrypted on the IPsec Security Association is encapsulated inside UDP port 4500 as well, thus providing a port to be used in the PAT device for translation. To visualize how this works and how the IP packet is encapsulated:

2014年1月19日 · Solved: Hi everyone, Need to confirm during IKE Phase 1 we use port UDP 500 IKE Phase 2 we use ports ESP -50 NAT-T UDP 4500 TCP-1000 ESP -50 NAT-T UDP 4500 TCP-1000 Regards Mahesh

2014年4月26日 · There is NAT/PAT in between R3 and ASA. as you use private IP address(192.168.98.6) to setup the ipsec session. IKE will detect NAT/PAT exist by NAT-D payload. IKE will use UDP 4500 to negotiate ISAKMP rather than UDP 500.

2014年3月7日 · Hi Experts, Is there any way by which we can find that the UDP port 500 is blocked at ISP side. My IPSec VPN configured between two cisco router in production network is not coming up and experts are saying that the ISP has blocked the port 500 somewhere in between, however ISP denying and saying ...

2020年2月21日 · For VPN Gateways that run a Cisco IOS Software Release later than 12.2(13)T, IPSec traffic is encapsulated into User Data Protocol (UDP) port 4500 packets. This feature is known as IPSec NAT Transparency . In order to initiate the tunnel from the local (PATed) peer, no configuration is needed.

2021年12月28日 · Because the NAT-T, in IKE Phase 2 (IPsec Quick Mode) encapsulates the Quick Mode (IPsec Phase 2) inside UDP 4500 . After Quick Mode negociation is completed, the Phase 2 is now ready to encrypt the data and ESP Packets are encapsulated inside UDP port 4500 as well, thus providing a port to be used in the NAT device to perform port address ...

2002年6月20日 · The advantage with the TCP option is that its most palatable to firewall admins. I don't know whether port 80 is your best option, though, depending on how you're planning on managing your concentrator. Also, firewall admins can get a bit antsey if you try and sneak an Ipsec connection through their firewall by tunneling over TCP/80.

2010年10月27日 · When a different IPSec NAT-T session passes through the PAT device, it will change the source port from 500 to a different random high port, and so on. The NAT device needs to be IPSec aware NAT, hence the negotiation for port 4500 will be automatic. Here is the RFC for the IPSec aware NAT (NAT-Traversal) for your reference:

2014年5月28日 · Hi Everyone, I am testing the VPN connection from user PC. When i test from user PC using IPsecoverTCP it uses protocol 10000. When i check on ASA - ASDM under connection details ike1-------------UDP Destination Port 500 IPsecOverTCP TCP Dst Port 10000 using Ipsecover UDP IKEv1--------...