I’m looking to create a backup link via cellular with a wAP LTE. The remote sites would have a standard internet connection (Cable, DSL, etc) with a tunnel (L2TP+ipsec probably, though EoIP+ipsec would be an option). The idea is to run OSPF+BFD on the main link and if it goes down, have an immediate re-route to the wAP LTE.
The question is, what is the lowest byte maintenance tunnel option?
I have 2 options for the backup link.
- put the wAP LTE into OSPF as well. This will cost my maintenance bytes but they are small, probably livable.
- don’t have the LTE link in OSPF, just have a static route on each side at distance 240 so it’s a circumstantial route when OSPF/BFD kills the primary path.
the basic question is, how many Mbits per month with EoIP, GRE, or L2TP eat up when ‘idle’. I may or may not be able to get a static or even public IP address on the LTE link, but this doesn’t really matter for the LTE because the tunnels will be 100% on the providers network (no open internet) and the data traversing the tunnel is already encrypted.
Thoughts?