I'm choosing router for brunch office among this models - 887VA-SEC-K9 or 887VA-K9. I want this router to can IPSEC site-to-site, GRE-tunnels and OSPF. I read the datasheet but I haven't understood several things about this model so I can't choose a right model. The datasheet says that default software is Advanced Security Feature Set for all 887 routers which supports IPSEC and GRE. Then I don't understand what are differences between 887VA-SEC-K9 or 887VA-K9? What does the word "SEC" mean? The second things aren't understood - I want the router to support OSPF. The Advanced IP Services can do it but there is two options too - SL-880-AIS and L-SL-800-SEC-K9. What are differences between them?
What should I choose to implement IPSEC-GRE-OSPF among this models and licenses?