If you are willing to build a chat application, one of the most common ways of doing so is to use an existing chat framework. However, if you are willing to develop an application from scratch, you will need to make several decisions and take several factors into consideration. One of the most important decisions that you will need to make is that of establishing the core functionality of the application.
While there are several instant messaging protocols in the market, we will discuss and compare two of the most popular candidates in this article – XMPP and WebSocket.
Both XMPP and WebSocket are communication protocols that allow systems to communicate with each other effectively. Here are the five key elements of a communication process defined by these protocols:
- Error recovery methods
These protocols free developers from worrying about purchasing dedicated cloud storage space for saving client data. Here, all client data is stored locally on the client devices. Moreover, the servers are used as an intermediate between the chat participants.
What Is XMPP And How Does It Work?
Extensible Messaging and Presence Protocol (XMPP), originally referred to as Jabber, is a highly preferred communication protocol for building real-time chat applications because of its open-source and extensible nature. The protocol is developed and maintained by the Jabber open community. XMPP servers provide users with their own cloud storage without any limitations for the chat participants.
XMPP has been used for building some of the most popular platforms, including WhatsApp and Google Talk.
Here are the resources required for developing an XMPP chat application:
- A Jabber server for setting up a message delivery system
- A Java, C, or Erlang developer
- YAWS server for managing the concurrent processes
- Mnesia database for storing data on the servers instead of the clients’ mobile devices.
The communication protocol uses XMP for exchanging data between the client and the server. When a client connects to an XMPP server through a chat application, they transmit information between each other. This information is called an XML “Stanza”, a basic unit of communication in XMP.
There are three types of Stanzas in XMPP-based communication:
- Message – Used for exchanging messages
- Presence – Used for exchanging online and subscription status
- IQ (Info/Query) – Used for controlling dynamic settings of the communication control over the server
XMPP is based on a decentralized architecture. XMPP-based communications assign a unique XMPP address that contains an IP address, domain name, and username for all users in a chat in order to process the communication channel effectively. Further, the data is bound with a secure transport layer (such as TCP/IP or HTTP) before getting exchanged between users.
What Is WebSocket and How Does It Work?
WebSocket is a popular communication protocol built for supporting full-duplex communication between a client application and the communication server. WebSocket allows users to send and receive data in real-time over a TCP connection between two or more peers.
As the protocol supports a full-duplex connection, WebSocket-based connections are also called persistent connections. These connections facilitate the sharing of data between two applications without requiring the client to make any request.
The working of WebSocket communication can be understood with the help of the following major steps:
- A WebSocket handshake is carried out through an HTTP request to establish a connection which is sent by the client to the server.
- If the server supports WebSocket and the connection is valid, the server would acknowledge the request and send a unique identifier in the header.
- The updated URL would now replace the original HTTP connection with a WebSocket connection.
- As the WebSocket is now in place, the client app can be used for exchanging data in real-time.
- The data or messages are exchanged as “Frames” with the help of WebSocket. These messages can be one or many depending upon their content. The client data or messages inside the frames are marked via XOR encryption.
- As opposed to XMPP, the WebSocket server is centralized and socket communications are established with the help of the server API.
Major Benefits Of XMPP
Here are some of the key benefits of XMPP:
Users can use XMPP for sending a variety of message types, including pictures, text, audio, video, etc. This gives them a range of options to undertake effective communication.
Architecture That Is Decentralized
With a decentralized architecture, anyone can set up an XMPP server.
XMPP facilitates developers to set up a separate storage server with its own encryption and security standards. This allows developers to increase the security of the platform if required.
XMPP allows developers to connect to non-Jabber programs and make use of special gateway services.
Major Drawbacks Of XMPP
Here are some of the major disadvantages of XMPP:
Inability To Assure Message Delivery
XMPP does not provide users with the ability to request the “message delivered” confirmation by default. The developers are required to set up the message receipts manually.
Lack Of Default Support For Binary Transfer Of Data
XMPP makes use of XMP for data transmission which does not support the binary transfer of data by default. This makes developers use protocols like HTTP for overcoming this shortcoming.
Transfer Limit On In-band Media Files
XMPP required developers to encode in-band data as base54 before it is transferred. This results in large data such as media file transfers being sent outside the band along with the coordinates to in-hand messages.
Owing to the decentralized architecture of XMPP, although the protocol allows users to run their own server, it reduces the overall speed of the connection.
Major Benefits Of WebSocket
Here are some of the major advantages of using WebSocket:
As opposed to XMPP, the communication connection in WebSocket is centralized and persistent. This results in the protocol being one of the fastest online communication methods.
No Limit On Open Sessions
WebSocket allows users to have an unlimited number of user sessions within a single application.
Lower Network Traffic
The network latency in WebSocket is never overused as multiple users are connected via a single connection.
Fast Deliverability Of Messages
Along with low latency, WebSocket has the ability to send data from the server to a client without the client needing to request the same using AJAX requests. This implies that there is almost no delay in receiving the messages once they are sent by the users.
Major Drawbacks Of WebSocket
Here are some of the major shortcomings of using WebSocket:
Despite utilizing WebSockets of WSS, the communication protocol is still fairly new and vulnerable to attacks such as DDoS and XSS. This reduces the overall security of the platform.
No Compatibility With Telnet Client
A WebSocket connection required developers to mask and frame the data being delivered, leading to the protocol being incompatible with a Telnet client.
Lack Of A Default Way Of Delaying Message Deliverability
An active WebSocket connection would always keep the ports open, leading to no default way of delaying message deliverability.
XMPP Vs WebSocket – Who Is A Clear Winner?
After looking at the pros and cons of both the communication protocols, it becomes fairly clear that they are two different approaches that serve different purposes for setting up a chat application. XMPP provides users with high security but lacks the speed of deliverability. On the other hand, WebSocket is not too secure but provides users with high deliverability.
The communication protocol you choose should depend on the specific needs and preferences of your organization. It is never advisable to hurry in making the final decision.
Go through your business model to find the most accurate answer to this question. Always make a thorough assessment of your requirements and consult a technical expert before choosing one of the two alternatives.