thinQmaster Virtual testing partner Adaptive practice exams that find your weak spots and drill them. Every answer explained. From $69
Enroll

thinQmaster

Find your exam

Five questions free, before you decide.

Step 1 · choose a vendor

In one of our camps? Your practice exams come with the tuition — they are on your study page already.

Routing & Switching · Advanced

Dynamic Multipoint VPN (DMVPN)

A Cisco hub-and-spoke VPN design using mGRE, NHRP and usually IPsec that can build dynamic spoke-to-spoke tunnels.

Definition

DMVPN lets spokes with dynamic public addresses register with a hub and run routing protocols over the overlay. Phase 1 is hub-and-spoke only, Phase 2 adds spoke-to-spoke tunnels but requires specific routes on spokes, and Phase 3 uses NHRP redirects and shortcuts so the hub can summarize. IPsec profiles protect the GRE traffic.

Example

tunnel protection ipsec profile DMVPN on the mGRE tunnel

Exam tip

Know which phase allows summarization at the hub (Phase 3) and which requires next-hop preservation (Phase 2).

Related terms