Introduction. In this blog, I aim to go a little deeper into how the different DMVPN phases work and how to properly configure the routing. DMVPN Explained. DMVPN stands for Dynamic Multipoint VPN and it is an effective solution for dynamic secure overlay networks. In short. Learn what DMVPN is, mechanisms used (NHRP, mGRE, IPSec) to achieve of the audience’s potential knowledge levels and explained it in terms that don’t.

Author: Mular Faerr
Country: Costa Rica
Language: English (Spanish)
Genre: Literature
Published (Last): 22 April 2011
Pages: 459
PDF File Size: 7.41 Mb
ePub File Size: 19.38 Mb
ISBN: 304-8-63640-868-4
Downloads: 8738
Price: Free* [*Free Regsitration Required]
Uploader: Melmaran

This sounds pretty cool but it introduces some problems….

Understanding Cisco Dynamic Multipoint VPN – DMVPN, mGRE, NHRP

This is great, we only required the hub to figure out what the public IP address is and all traffic can be sent from spoke to spoke directly. It should look for a better way using NHRP resolution. With mGRE, all spokes are configured with only one tunnel interface, no matter how many spokes they can connect to. At this point, explaijed spokes can now modify their routing table entries to reflect the NHRP shortcut route and use it to reach the remote spoke.

Understanding Cisco Dynamic Multipoint VPN – DMVPN, mGRE, NHRP

DMVPN consists of two mainly deployment designs:. All spokes connect directly to the hub using a tunnel interface. In an old postdatedI explained various types of VPN technologies. In seven years several things have changed: In case no routing protocol is used in our VPN network, the addition of one more spoke would mean configuration changes to all routers so ddmvpn the new spoke is reachable by everyone.

Forum Replies Rene, When would we choose to use Phase 1, 2, or 3, and why? Share on Twitter Tweet. The disadvantage of phase 1 is that there is no direct spoke to spoke tunnels.


All tunnel interfaces are part of the same network. The HQ for example has one tunnel with each branch office as its destination.

DMVPN provides a number of benefits which have helped make them very popular and highly recommended. Join us on LinkedIn! By using our website, you agree to our use of cookies Read more. Lastly, traffic explzined spokes in a point-to-point GRE VPN network must pass through the hub, wasting valuable bandwidth and introducing unnecessary bottlenecks. We use cookies to give you the best personal experience on our website.

If you like to keep on reading, Become a Member Now! When we use them, our picture could look like this:. When there is traffic between the branch offices, dnvpn can tunnel it directly instead of sending it through the HQ router.

In both cases, the Hub router is assigned a static public IP Address while the branch routers spokes can be assigned static or dynamic public IP addresses. Initially, and that is the key word all spoke to spoke packets are switched across the hub. The hub is the only router that is using a multipoint GRE interface, all spokes will be using regular point-to-point GRE tunnel interfaces. Routed versus routing protocols Send WhatsApp alert during a network fault.

Email Updates Enter your email address to receive notifications of new posts. Spoke3 explaiined directly to Spoke2 with its mapping information. Articles To Read Next: As stated, DMVPN greatly reduces the necessary configuration in a large scale VPN network by eliminating the necessity for crypto maps and other configuration requirements.

Above we have two spoke routers NHRP clients which establish a tunnel to the hub router. Explained As Simple As Possible. Furthermore, spoke-to-spoke traffic no longer needs to pass through the hub router but is sent directly from one spoke to another. Follow Us on Twitter! Because mGRE tunnels do not have a tunnel destination defined, they cannot be used alone.

  3RG4013 3AB00 PDF

Allow spokes to build a spoke-to-spoke tunnel on demand with these restrictions: Full Access to our Lessons. We use cookies to ensure that we give you the best experience on our website. If you continue to use this site we will assume that you are happy with it.

You may cancel your monthly membership at any time. Share on Facebook Share. Deal with bandwidth spikes Free Download.

Send this to a friend Your email Recipient email Send Cancel. Because all spoke-to-spoke traffic in DMVPN Phase1 always traverses the hub, it is actually inefficient to even send the entire routing table from the hub to the spokes.

Introduction to DMVPN |

A few seconds later, spoke1 decides that it wants to send something to spoke2. Hello Heng This is a very good question. Explauned on Digg Share. Right now we have a hub and spoke topology. For instance, to reach Cisco DMVPN uses a centralized architecture to provide easier implementation and management for deployments that require granular access controls for diverse user communities, including mobile workers, telecommuters, and extranet users.

Unified Communications Components – Understanding Your The Hub router undertakes the role of the server while the spoke routers act as the clients.

The request gets forwarded from HUB to Spoke3. Share on LinkedIn Share. Above we have one router that represents the HQ and there are four branch offices.