Share internet connection helpers.

[sque]

There is a common scenario right now in HWMN where peers want to share their internet connection with other peers. It would be nice to include the appropriate packages for this purpose and maybe a script or a Luci mod to setup and monitor this procedure.

Right now there is no perfect solution for this issue that addresses all requirements.

Requirements

• Support authentication and preferably encryption
• Be lightweight enough to run on routerboard or even better on ubiquity nanobridge
• Manage properly the extra routes.

Solutions that have been tested:

• OpenVPN
  • Pros: Strong authentication, encryption, flexible configuration
  • Cons: Very heavy for embedded devices. On 750gl maximum speed 10mbps
• GRE Tunnel
  • Pros: Extremely lightweight, 100mbps with negligible CPU footprint, flexible
  • Cons: No authentication or encryption.