A company has recently established a remote office and needs to securely connect its network with the main office. The network administrator chooses to implement a tunneling protocol that can encapsulate a variety of network layer protocols over IP networks. Which protocol should the administrator implement considering the need for simplicity and compatibility with disparate networks?
IPSec (Internet Protocol Security)
Generic routing encapsulation (GRE)
SSL/TLS (Secure Sockets Layer/Transport Layer Security)
L2TP (Layer 2 Tunneling Protocol)