RSVP-TE (Resource Reservation Protocol Traffic Engineering) is a protocol used in computer networking to set up explicit paths through a network for data transmission, particularly in Multiprotocol Label Switching (MPLS) networks.

RSVP-TE is an extension of the RSVP protocol, which is used for signaling and reservation of network resources in general. In an MPLS network, RSVP-TE is used to establish Label Switched Paths (LSPs) between network nodes, based on explicit routes specified by the network administrator.

The RSVP-TE protocol enables routers to communicate with each other to establish a specific path for a particular flow of traffic, ensuring that the necessary resources are reserved and the data is transmitted through the network in a predictable and efficient way. This is particularly useful for applications that require a certain level of Quality of Service (QoS) or bandwidth guarantees, such as video conferencing or real-time multimedia streaming.

RSVP-TE works by exchanging messages between routers in order to establish and tear down LSPs, and to make reservations for the required network resources along the path. These messages contain information such as the source and destination IP addresses, the type of traffic, the bandwidth requirements, and any other relevant parameters needed to establish the LSP.

Overall, RSVP-TE is an important protocol for traffic engineering and QoS in MPLS networks, providing a way to reserve network resources and establish explicit paths for data transmission, ensuring efficient use of network resources and better network performance

source: chatGPT