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Viptela Documentation

Viptela Terminology

The following figure summarizes the terminology used to describe a Viptela overlay network.


Domain ID

A domain is a logical grouping of vEdge routers and vSmart controllers that demarcates the span of control for the vSmart controllers. Each domain is identified by a unique integer, called the domain ID. Currently, you can configure only one domain in a Viptela overlay network.

Within a domain, vEdge routers can connect only with the vSmart controllers in their own domain. The vBond orchestrator is aware of which vSmart controllers are in which domain, so that when new vEdge routers come up, the vBond orchestrator can point those routers to the vSmart controllers in the proper domain. However, the vBond orchestrator is never a member of a domain.>

Within a domain there is full synchronization of routing information among the vSmart controllers and vEdge routers, and there is scope for route aggregation and summarization. An organization can divide up its network into domains to serve desired business purposes. For example, domains can correspond to a large geographic area or to data centers so that each data center and the branches for which it is responsible are contained within a single domain.

OMP Routes

On vSmart controllers and vEdge routers, OMP advertises to its peers the routes and services that it has learned from its local site, along with their corresponding transport location mappings, which are called TLOCs. These routes are called OMP routes, to distinguish them from standard IP routes. It is through OMP routes that the vSmart controllers learn the network topology and the available services.

The Viptela​ control plane architecture uses three types of OMP routes:

  • OMP routes—Prefixes that establish reachability between end points that use the OMP-orchestrated transport network. OMP routes can represent services in a central data center, services at a branch office, or collections of hosts and other end points in any location of the overlay network. OMP routes require and resolve into TLOCs for functional forwarding. In comparison with BGP, an OMP route is the equivalent of a prefix carried in any of the BGP AFI/SAFI fields.
  • Transport locations (TLOCs)—Identifiers that tie an OMP route to a physical location. The TLOC is the only entity of the OMP routing domain that is visible to the underlying network, and it must be reachable via routing in the underlying network. A TLOC can be directly reachable via an entry in the routing table of the physical network, or it must be represented by a prefix residing on the outside of a NAT device and must be included in the routing table. In comparison with BGP, the TLOC acts as the next hop for OMP routes.
  • Service routes—Identifiers that tie an OMP route to a service in the network, specifying the location of the service in the network. Services include firewalls, Intrusion Detection Systems (IDPs), and load balancers.

Site ID

A site is a particular physical location within the Viptela overlay network, such as a branch office, a data center, or a campus. Each site is identified by a unique integer, called a site ID. Each Viptela device at a site is identified by the same site ID. So within a data center, all the vSmart controllers and any vEdge routers are configured with the same site ID. A branch office or local site typically has a single vEdge router, but if a second one is present for redundancy, both routers are configured with the same site ID.

System IP Address

Each vEdge router and vSmart controller is assigned a system IP address, which identifies the physical system independently of any interface addresses. This address is similar to the router ID on a regular router.​ The system IP address provides permanent network overlay addresses for vEdge routers and vSmart controllers, and allows the physical interfaces to be renumbered as needed without affecting the reachability of the Viptela device. You write the system IP address as you would an IPv4 address, in decimal four-part dotted notation.


A TLOC, or transport location, identifies the physical interface where a vEdge router connects to the WAN transport network or to a NAT gateway. A TLOC is identified by a number of properties, the primary of which is an IP address–color pair, which can be written as the tuple {IP-address, color}. In this tuple, IP address is the system IP address and color is a fixed text string that identifies a VPN or traffic flow within a VPN. OMP advertised TLOCs using TLOC routes.

Additional Information

For a description of the elements in a Viptela overlay network, see Components of the Viptela Solution. For an understanding of how you put together an overlay network using Viptela software and hardware, see Constructing a Basic Network Using Viptela Components. For examples of how the components of the overlay network work, see the Validated Examples.

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