Ports and Protocols

A protocol is a method of communication between computers and other electronic devices on the same network. It defines the rules or process for exchanging data. Protocols are a common language so that communication can happen despite differences in hardware, software, and so on. Examples of commonly-known protocols are HTTP, HTTPS, and FTP.

There are several kinds of protocols that work together at the same time. Each kind of protocol, or layer of network communication, has a different role. They work together to provide a flexible model for sending and receiving data. For example, protocols in the internet layer break data into packets when sending and reassembles them when receiving. IP, or Internet Protocol, is an example of a protocol in this layer.

The protocols that CXone uses are in the following layers: 

  • Transport: Protocols in the transport layer transmit the data packets and ensure that they arrive in sequence with no errors.
  • Application: Protocols in the application layer services that are used on the network, such as sending and receiving files or email messages. Some protocols may also maintain and control sessions in an application.

A port in computer networking is a software-based virtual starting and stopping point for network connections. They're managed by the computer's operating system. Ports are identified with numeric IDs and are associated with specific protocols, processes, or services. There are standardized assignments for certain protocols. For example, port 80 is reserved for all HTTP traffic.

Ports work together with IP addresses to ensure that data gets where it needs to go. The IP address identifies the destination computer. The port identifies the application or service on the computer where the data needs to go. For example, when you type a website address in the address bar of your web browser, it communicates over port 80 to request data from that address, then loads the received data—the requested webpage—for you to view.

Ports and Protocols in CXone

The following are transport layer protocols. They aren't assigned to specific ports. The application layer protocols work with one of the transport layer protocols, depending on the specific needs of the application.

  • TCP: Transmission Control Protocol. Creates a secure connection before sending data, then verifies the transmission after it's complete to ensure the entire message was sent. It can resend data if needed. It's reliable but slower than UDP because it requires a connection before sending any data. TCP is often used for email, texting, web browsing, and file transfers.
  • UDP: User Datagram Protocol. Sends data without first establishing a connection. Unlike TCP, UDP does not confirm receipt or check for errors. It's faster than TCP but less reliable. UDP is often used for real-time data transfers such as streaming or video chat because it avoids delays.

The following are application layer protocols, along with the standard port number for each one. CXone uses standard ports when possible.

  • FTP: File Transfer Protocol. Allows the transfer of files. Port numbers: 20 (TCP), 21 (TCP).
  • HTTP: Hypertext Transfer Protocol is a commonly-known protocol. It's used on the internet and allows the exchange of data between many types of computers and devices. Port number: 80 (TCP).
  • HTTPS: is similar to HTTP, except it adds security in the form of encryption. Port number: 443 (TCP).
  • RTP: Real-time Transport Protocol. Transmits data as numbered, time-stamped packets. It's often used to transmit audio and video data, including telephony, WebRTC, and streaming media. Because packets are sequence-numbered, they can be reassembled if they arrive out of order. RTP is an application layer protocol despite having "transport protocol" in the name. Port numbers: varies.
  • SFTP: Secure File Transfer Protocol. Allows the secure transfer of files. It uses secure shell encryption to add security to file transfers. Port number: 22 (TCP).
  • SIP: Session Initiation Protocol. Initiates, maintains, and terminates communication sessions over the internet or private IP (Internet Protocol) networks. Sessions can be voice, video, or messaging. SIP supports secure transmission using Transport Layer Security (TLS). Port numbers: 5060 (UDP or TCP), 5061 (TCP; for secure SIP communications).
  • SMTP: Simple Mail Transfer Protocol. Sends and receives email messages. Port number: 25 (TCP), 587 (TCP).
  • SRTP: Secure Real-time Transport Protocol. Adds a layer of security to RTP. It adds encryption and authentication to RTP transmissions. It's an extension of the RTP protocol. Port number: varies.

Inbound vs. Outbound

When discussing ports in CXone, the concepts of inbound and outbound are defined as follows: 

  • Outbound: Data flowing from your initiation point to CXone.
  • Inbound: Data flowing from CXone to your servers.

This is different from the definitions used in other areas of connectivity, such as when discussing the A and B legs of an interaction.

Discover Your Ports and Protocols by Application

Use the Discover Connectivity Requirements online help wizard to find the list of required ports for the CXone applications you use in your contact center.