What is TE in MPLS?
What is TE in MPLS?
MPLS Traffic Engineering (MPLS TE) is a growing implementation in today’s service provider networks. MPLS adoption in service provider networks has increased manifold due to its inherent TE capabilities. This chapter provides you with information on the operation and configuration of MPLS TE on Cisco routers.
Why setup priority of a TE tunnel Cannot be lower than its holding priority?
The setup priority of a tunnel should not be lower than its holding priority; otherwise, it can preempt another tunnel, but in turn it can be preempted by that other tunnel. This is why in Cisco IOS, you cannot configure a setup priority that is lower than the holding priority.
What is a TE tunnel?
The Multiprotocol Label Switching (MPLS) Traffic Engineering (TE): Tunnel Source feature allows you to specify the IP address assigned to an interface as the source IP address for control packets.
How do you set up te?
Configure the MPLS TE tunnel.
- Step 1: Globally Enable MPLS TE. The first step in the configuration of the head-end router is to globally enable MPLS TE.
- Step 2: Configure Interface Parameters.
- Step 3: Configure the Backbone IGP for MPLS TE.
- Step 4: Configure the MPLS TE Tunnel.
What is MPLS RSVP-TE?
RSVP-TE is used to establish MPLS transport LSPs when there are traffic engineering requirements. It is mainly used to provide QoS and load balancing across the network core, and includes the ability to control all-optical networks.
What is required for implementing MPLS TE?
Enabling MPLS TE. Cisco MPLS TE requires configuration at the node and interface (link) levels. The configuration involves mainly the definition of MPLS TE and Resource Reservation Protocol (RSVP) behavior. In addition, you may want to enable the TE extensions for your IGP to perform constraint-based routing.
What is setup and holding priority in TE tunnel?
The setup priority and holding priority of an MPLS TE tunnel determines the importance of the tunnel. A tunnel that has a higher setup priority than the holding priority of another tunnel can preempt the resources of the second.
What is the default periodic flood time for MPLS traffic engineering?
MPLS quiz
| Question | Answer |
|---|---|
| What is the default periodic flood time for MPLS TE? | 180 seconds |
| What method is used to calculate best path in MPLS TE? | constrained SPF |
| ____________allow for a tunnel to be built based on a series of explicitly defined next hops Include or exclude. | Explicit path-options |
What are two characteristics of MPLS TE tunnels?
Correct Answer: B
- They are unidirectional.
- The headend and tailend routers of the tunnel must have a BGP relationship.
- They are run over Ethernet cores only.
- They use RSVP to provide bandwidth for the tunnel.
- They require EIGRP to be running in the core.
Why do we need link state protocols in MPLS TE?
Link-state protocols (IS-IS and OSPF) provide the flooding capabilities that are required to distribute these attributes. LSRs use this information to build a TE topology database. This database is separate from the regular topology database that LSRs build for hop-by-hop destination based routing.
How many labels are used in MPLS TE?
two labels
The packets forwarded according to MPLS-TE have a stack of two labels (imposed by the ingress router). The top-most label identifies a specific LSP to use to reach another router at the other end of the tunnel. The second label indicates what the router at the far end of the LSP should do with the packet.
