gre tunnel explained

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  • MikroTik Site to Site GRE Tunnel Configuration with IPsec

    VPN (Virtual Private Network) is a technology that provides a secure tunnel across a public network. A private network user can send and receive data to any remote private network using VPN Tunnel as if his/her network device was directly connected to that private network. MikroTik provides GRE (Generic Routing Encapsulation) tunnel that is used to create a site to site VPN tunnel. GRE tunneling protocol which can encapsulate a wide variety of protocols creating a virtual point-to-point link was originally developed by Cisco. GRE is a stateless tunnel like EoIP and IPIP. That means if the remote end of the tunnel goes down, all traffic that was routed over the tunnels will get blackholed. To solve this problem, RouterOS have added ‘keepalive’ feature for GRE tunnels. By default keepalive is set to 10 seconds and 10 retries. GRE adds an outer header mentioning the entry point of the tunnel (SourceIP) and the exit point of the tunnel (DestinationIP) but the inner packet is kept unmodified. GRE tunnel only encapsulates IP packets but does not provide authentication and encryption. GRE tunnel with IPsec ensures IP packet encapsulation as well as authentication and encryption. IPsec usage makes your packets secure but [...]

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    MikroTik User Manager RADIUS Installation on RouterOS 7 |   July 5, 2022

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    MikroTik Site to Site EoIP Tunnel with IPsec |   March 21, 2018

    VPN (Virtual Private Network) is a technology that provides a secure tunnel across a public network. A private network user can send and receive data to any remote private network using VPN Tunnel as if his/her network device was directly connected to that private network. MikroTik provides EoIP (Ethernet over IP) tunnel that is used to create a site to site VPN. EoIP tunneling is a MikroTik RouterOS protocol that creates an Ethernet tunnel between two MikroTik Routers on top [...]

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    MikroTik Site to Site VPN with L2TP/IPsec |   March 3, 2018

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    OpenVPN Client Configuration in Windows 10/11 |   June 29, 2022

    OpenVPN is an excellent VPN solution for transmitting data securely over public network. Configuring an OpenVPN Server either on MikroTik RouterOS or Ubuntu Server, we can access local servers or devices from remote place using Windows 10/11, Android or MacOS.  How to configure OpenVPN Server in Ubuntu Server was discussed in the previous article. In that article, I also discussed how to create a new OpenVPN client (for Windows OS) who will be able to connect the OpenVPN Server. So, [...]

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    MikroTik UserMan RADIUS Server Customers, Users and Routers |   November 13, 2017

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