5. Session Layer

SSL and TLS is a tricky component, some sources say it fits in the presentation layer due to its encryption but it does play an important part with establishing secure sessions between endpoints.

Protocol Name Description Common Usage
RPC (Remote Procedure Call) A protocol that allows a program to execute a procedure (subroutine) on another address space (often on a remote machine). Used in client-server models, allowing distributed applications to execute code remotely.
NetBIOS (Network Basic Input/Output System) A session layer protocol that provides communication services for applications in local area networks (LANs). Primarily used in legacy Windows networking to support file sharing and printer services.
SMB (Server Message Block) A protocol that facilitates file sharing, printer sharing, and network browsing between computers. Widely used in Windows networks for file and printer sharing, also supported by Linux and macOS.
NFS (Network File System) A protocol that allows access to files over a network as if they were local files. Used for file sharing in UNIX/Linux systems, providing transparent access to remote files.
FTP (File Transfer Protocol) A protocol for transferring files over a network. It uses a client-server model for file access, transfer, and management. Commonly used for website management, downloading, and uploading files to servers.
Telnet A protocol that provides a command-line interface for remote administration of devices over a network. Used primarily for remote management of devices or servers, though rarely used today due to security concerns.
SSL/TLS (Secure Sockets Layer/Transport Layer Security) Protocols for establishing encrypted connections between networked applications, ensuring secure data transmission. Used in HTTPS for secure web browsing, email encryption (SMTPS), and other secure communications.
H.323 A protocol suite used for multimedia communications, such as voice, video, and data conferencing. Commonly used for voice-over-IP (VoIP) applications and video conferencing systems.
XMPP (Extensible Messaging and Presence Protocol) A communication protocol for message-oriented middleware based on XML. It supports real-time messaging, presence, and collaboration. Widely used in instant messaging, VoIP, and presence systems, notably in Google Talk and Jabber.
SIP (Session Initiation Protocol) A protocol used for initiating, maintaining, and terminating real-time sessions in VoIP, video conferencing, and instant messaging. Common in VoIP services and video conferencing platforms like Skype, Zoom, and Webex.
MAPI (Messaging Application Programming Interface) A protocol used by Microsoft Outlook to send and receive emails, manage calendars, and other messaging features. Primarily used in Microsoft Exchange Server environments for email and collaboration features.
RDP (Remote Desktop Protocol) A proprietary protocol developed by Microsoft for remote desktop access. Used for remote administration and remote access to Windows-based systems.
L2TP (Layer 2 Tunneling Protocol) A protocol used in VPNs that enables tunneling of data between two endpoints over the internet, often paired with IPsec for encryption. Used for secure, private connections in VPN implementations.
BEEP (Blocks Extensible Exchange Protocol) A framework for building application protocols, providing features like reliable delivery, security, and message framing. Used for building custom communication protocols in secure, reliable messaging systems.

These protocols manage and control the dialogues between computers, ensuring that data is exchanged without disruption, allowing for reliable communication during interactions between client-server or peer-to-peer systems.