Computer Networks

It is defined in RFC 2205, and used to create quality of service.

It is used for establishing the communication session parameters at both the ends.

This is used to indicate server failure response.

It provides user interfaces and support for services, such as electronic mail, remote file access and transfer and shared database management.

It is concerned with the syntax and semantics of the information exchanged between two systems.

Statements 1, 2 and 3 are correct.

This layer is responsible for the source to destination delivery of a packet, possibly across multiple networks.

It establishes, maintains, and synchronizes the interaction among communicating systems.

It ensures that the whole message arrives intact in and order , overseeing both error and flow control at the source to destination level.

It is responsible for functions such as framing error control, flow control, physical addressing and access control mechanisms.

The Reverse Address Resolution Protocol (RARP) is a computer networking protocol used by a host computer to request its Internet Protocol (IPv4) address from an administrative host, when it has its Link Layer or hardware address available, such as a MAC address.

UDP uses a simple transmission model with a minimum of protocol mechanism. It has no handshaking dialogues and thus exposes any unreliability of the underlying network protocol to the user's program.

Bit Map Protocol is also a contention system. In Bit Map Protocol, the desire to transmit is broadcast before the actual transmission. Such protocols are called reservation protocols.

Network layer is responsible for packet forwarding, including routing through intermediate routers. Hence, routing is a concern of this layer.

Gopher protocol is a TCP/IP application layer protocol designed for distributing, searching, and retrieving documents over the Internet. Gopher ecosystem is often regarded as the effective predecessor of the World Wide Web.