In computer networking, the term upper layer protocol refers to a more abstract protocol when performing encapsulation

Encapsulation (networking)

In computer networking, encapsulation is a method of designing modular communication protocols in which logically separate functions in the network are abstracted from their underlying structures by inclusion or information hiding within higher level objects....

, in particular it is often used to describe the protocols above the network layer

Network layer

The network layer is layer 3 of the seven-layer OSI model of computer networking.The network layer is responsible for packet forwarding including routing through intermediate routers, whereas the data link layer is responsible for media access control, flow control and error checking.The network...

.

In discussions of the Internet Protocol Suite

Internet protocol suite

The Internet protocol suite is the set of communications protocols used for the Internet and other similar networks. It is commonly known as TCP/IP from its most important protocols: Transmission Control Protocol and Internet Protocol , which were the first networking protocols defined in this...

, the term upper layer protocols usually refers to the protocols above the Internet Layer

Internet layer

The internet layer or IP layer is a group of internetworking methods in the Internet protocol suite, commonly also called TCP/IP, which is the foundation of the Internet...

 (e.g. Transmission Control Protocol

Transmission Control Protocol

The Transmission Control Protocol is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite, complementing the Internet Protocol , and therefore the entire suite is commonly referred to as TCP/IP...

, which is in the Transport Layer

Transport layer

In computer networking, the transport layer or layer 4 provides end-to-end communication services for applications within a layered architecture of network components and protocols...

). In the internet protocol suite, IP is the lower layer protocol to UDP and TCP; likewise UDP and TCP are two upper layer protocols for IP.

The term contrasts with lower layer protocol

Lower layer protocol

In computer networking, the term lower layer protocol refers to a more specific protocol when performing encapsulation.In discussions of the Internet Protocol Suite, lower layer protocols are usually considered to be protocols below the IP level, i.e. the protocols in the Link Layer.The term...

which refers to a more specific protocol.