How do I configure my Cisco ASA5505 to allow 'outbound' vpn connections using "IPSec over TCP / port 10000"? Users on my internal network are able to use the Cisco VPN client (v5.0.02) and connect through the ASA to remote networks via IPSec over UDP, but they are unable to connect to networks that require "IPSec over TCP" using TCP port 10000.
It is at the TCP (and UDP) level that the concept of a "port" arises. A port is simply a way of distinguishing between different connections to a given machine. Remember, IP only lets us target the machine itself (by IP number). Once data arrives to the machine, it needs to be sent to the appropriate process by the operating system. Layer Two Tunneling Protocol (L2TP) uses UDP port 1701 and is an extension of the Point-to-Point Tunneling Protocol. L2TP is often used with IPSec to establish a Virtual Private Network (VPN). Point-to-Point Tunneling Protocol (PPTP) uses TCP port 1723 and IP protocol 47 Generic Routing Encapsulation (GRE). PPTP provides a low-cost, private —Specify the local and remote UDP port numbers. Each configured proxy ID will count towards the IPSec VPN tunnel capacity of the firewall. This field is also used as an IKEv2 traffic selector. One of the two core security protocols in IPSec is the Authentication Header (AH). This is another protocol whose name has been well chosen: AH is a protocol that provides authentication of either all or part of the contents of a datagram through the addition of a header that is calculated based on the values in the datagram. UDP port 500 is the ISAKMP port for establishing PHASE 1 of IPSEC tunnnel. VPN-GW1-----nat rtr-----natrtr-----VPNGW2. If two vpn routers are behind a nat device or either one of them, then you will need to do NAT traversal which uses port 4500 to successfully establish the complete IPEC tunnel over NAT devices. The default port (and most common) is tcp/10000 but any port will do good. But, the port must be specified in the head end with the ‘ crypto isakmp ipsec-over-tcp port 10000′ command. Answers Use ipsec command options -n, -g, and -l to identify resources by their policy specification name. Defensive filters are not configured in Policy Agent policy files. You can add defensive filters to the TCP/IP stack in response to a detected intrusion with the ipsec command defensive filter add command. The defensive filter's name is assigned
This is a list of TCP and UDP port numbers used by protocols of the Internet protocol suite for operation of network applications.. The Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP) needed only one port for full-duplex, bidirectional traffic.
Jul 03, 2017 · TCP and UDP aren’t the only protocols that work on top of IP. However, they are the most widely used. How TCP Works. TCP is the most commonly used protocol on the Internet. When you request a web page in your browser, your computer sends TCP packets to the web server’s address, asking it to send the web page back to you. Dec 07, 2005 · To allow PPTP tunnel maintenance traffic, open TCP 1723. To allow PPTP tunneled data to pass through router, open Protocol ID 47. L2TP over IPSec To allow Internet Key Exchange (IKE), open UDP 500. To allow IPSec Network Address Translation (NAT-T) open UDP 4500. To allow L2TP traffic, open UDP 1701.
Implementations MUST support TCP encapsulation on TCP port 4500, which is reserved for IPsec NAT Traversal. Beyond a flag indicating support for TCP encapsulation, the configuration for each peer can include the following optional parameters: Alternate TCP ports on which the specific TCP Responder listens for incoming connections.
Jul 10, 2020 · It allows you to add IP restrictions, and TCP/UDP level encryption to applications which may not otherwise support it. Prerequisites IP Protocol 50 (ESP) in/out IP Protocol 51 (AH) in/out UDP port 500 in/out Maybe TCP/UDP 88 (if you are authenticating) Maybe UDP 4500 (NAT)