Good morning everyone. I’m running a business where 5 locations communicate with each other with MPLS managed by the ISP.
Due to high costs and the idea of creating a VOIP telephone switchboard to communicate between the various offices, they decided to cancel MPLS and called me to propose an alternative solution.
I was thinking of using gre /30 tunnels for the data part and managing the routing with RIP. The doubt arises, if by chance they wanted to insert a backup connection on each of the 5 offices. Maybe in that case it’s better to use a VPN that doesn’t need a public IP on both ends.
Also, in order to have no NAT in the telephony part, I was thinking of using L2TPv3 to guarantee a Layer2. What do you think about it, am I proposing a reliable solution? Or am I completely off track?
I am attaching a diagram of how I planned to structure the network.
hello.
Due to high costs and the idea of creating a VOIP telephone switchboard to communicate between the various offices, they decided to cancel MPLS and called me to propose an alternative solution.
well, in case you are interested, cost and effort wise - there are plenty of online pbx solutions on the internet. which probably with reasonable affordable pricing.
but, if you want to build the solution yourself - maybe cloud based single asterisk pbx could be an option 
you could tweak it as you need. hence you only need internet link and some nat, qos setup for your voip traffic.
I was thinking of using gre /30 tunnels for the data part and managing the routing with RIP. The doubt arises, if by chance they wanted to insert a backup connection on each of the 5 offices. Maybe in that case it’s better to use a VPN that doesn’t need a public IP on both ends.
split routing. split tunnel.
one vpn hub normally need 1 public ip. the rest will be just fine behind cgnat whatever. but better to test it first.
well, no need to worry. you will be just fine that is how we can get better hands on experience.
but, better to lab your diagram first, just to make sure your settings will work seamlessly.
good luck
i was thinking that maybe more than using l2tpv3, it is preferable to use a vxlan inside the gre tunnel.
i was thinking that maybe more than using l2tpv3, it is preferable to use a vxlan inside the gre tunnel.