The other way of providing Data Center Interconnectivity besides OTV is VxLAN. VxLAN has ben developed through a few years and despite at the beginning was considered as a solution that enabled spanning VLANs across the single Data Center, nowadays is considered as a solution equal or even better to compare with OTV and enables us spanning VLANs across different geographical locations.

We usually think about multicast in the context of streaming video, audio, gaming, live transmissions, but also routing protocols use multicast to send updates. Moreover, if you are going to deal with Data Center Interconnect,  you gonna come across multicast trafic. But, before we go over the lab let’s get to know what is the multicast transmissions, what elements consists of and how is being used.


Overlay Transport Virtualization is the technology that you may encounter, if you are going to span your Data Center across different geographical location with full retaining of layer 2 information. It literally enables you connectivity between 2 servers within the same Vlan that are placed far away of each other. 



In the course of time the old-fashioned model od Data Center became inefficient especially when requirements regarding the traffic from North-South (client-server) have changed itself to East-West (server-server) and demanding applications started to be “hungry” for more than Gigabit links bundled via Portchannel. Also the better redundancy with non blocking links has started to be desirable.  All this problems resolved   new Spine-Leaf architecture and Application Centric Infrastructure as an easing in management.

The difference between phase 2 and 3 regarding DMVPN is slight at a first glance. In this article we will find out how to properly configure Phase 3, especially we focus on  NHRP protocol and its role. At the end we will establish full reachability between 2 spokes with utilization of EIGRP.

Sham Link feature is necessary if we want to deploy backdoor link between 2 OSPFs domains belong to the same area but split by MPLS. The issue that we will come across is a result that backdoor link will have priority over the MPLS.

We may come across on interesting issue if we get the same prefix from external BGP AS and directly via OSPF process. It may happen if we want to have another link to the destination but not neccesarily via another eBGP link. The problem that we will definetely come across on is just  another variation of suboptimal routing. 

MPLS works based on underlying IGP protocol. It may be OSPF or IS-IS, but whatever we choose, we are still dependant to IGP path calculation. Of course we may manipulate the cost of path and this way provide traffic enginering, but MPLS has its own mechanism.

Simple Modular Policy Framework and application inspection enable us for example inspection of FTP connection. When we use passive mode we need beside opened  port 21 as a control channel also any random port as a data channel. Thanks to MPF and  traffic inspection ASA knows what is the number of this random port and entire connection is enable. Great!

In this lab from the scratch we will implement fully working MPLS core with Layer 3 VPN and MP-BGP vpnv4 on the provider edge routers. Also we will achieve full connectivity between customers edge routers with routing protocols. At the end we will find out how to implement “extranets” and “shared services”, thanks to which we will be able to share for example Internet for MPLS Layer3 VPN customers, still keeping their networks separately.