Traffic Engineering Path

[abdul.qadir5001]

How it is possible that Traffic Engineering (TE) helps to forward traffic on that path that is not available in the routing table.

[Joseph W. Doherty]

Unsure what you're really asking, but possibly an item where traffic engineering might "help" is when a path that's not in the routing table might be used for some reason you want to send some traffic, that you select, across that path but preclude other traffic from also using that path.

[Harold Ritter]

Hi Abdul,

There is several ways you can push traffic through the MPLS TE tunnel.

1. You can use a static route.

ip route 192.168.1.0 255.255.255.0 Tunnel1

2. Autoroute announce under the tunnel interface

This will cause local router to include the TE tunnel in the SPF calculation. Destinations downstream of the tunnel tail-end will therefore use the TE tunnel.

3. Forwarding adjacencies

This will cause all routers in the IGP to include the TE tunnel in the SPF calculation.

4. Class based Tunnel Selection (CBTS)

This will cause traffic to be forwarded to different tunnel interfaces based on their Class of Service value.

Please refer to the MPLS TE documentation for more information:

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/mp_te_path_setup/configuration/15-s/mp-te-path-setup-15-s-book.html

Regards,

[MHM Cisco World]

I will talk about this TE RSVP "explicit"

RSVP use special Message this message contain the explicit list which list the all next hop until the destination.
R1-R2-R3 
R1 is the Tunnel Head 
R1 will send RSVP to all interface that enable it. 
R1 will inform the R2 that the next-hop must be the R3.
R2 will use R3 as next hop. 

Now what is different between the MPLS TE and MPLS 
MPLS normally depend on OSPF for the next hop and the packet it receive will be label with next hop according of OSPF 
MPLS TE now use the next-hop list in RSVP to label the packet with same next-hop list and not according to OSPF.