Introduction

Since its inception, Apache Kafka has been widely recognized for its robust data streaming capabilities, making it the go-to solution for numerous companies handling real-time data. However, Kafka’s architecture has its own limitations, including issues with scalability, rebalancing, node failure management, cloud-native compatibility, and jitter. In light of these challenges, organizations using Kafka are exploring alternative systems in the streaming space, such as Apache Pulsar.

Pulsar has been making waves in the messaging and streaming domain. Although Pulsar’s creation was inspired by Kafka’s classic architecture, and it shares familiar concepts like topics and brokers, it adopts an entirely different approach to managing computing and storage. Born for the cloud-native era, Pulsar features a decoupled architecture, which allows for independent scaling of its computing and storage layers. This innovative design effectively solves some of the key issues experienced by Kafka users. Moreover, Pulsar is designed natively with a suite of enterprise-grade features, including geo-replication, multi-tenancy, and tiered storage, positioning Pulsar as an attractive alternative to Kafka users.

Nevertheless, Kafka has been the major solution for a long time for many organizations and their applications are already bound with it. They might be reluctant to make the migration due to different organizational, operational, or technical considerations. 

This raises an interesting question: Is there a way for organizations to keep using their Kafka applications without major changes while leveraging Pulsar’s infrastructure and superior messaging and streaming technology?

Pulsar features a protocol handler mechanism that allows teams to leverage the best of both worlds. StreamNative has implemented the Kafka wire protocol by leveraging the existing components (for example, topic discovery, the distributed log library – ManagedLedger, and cursors) that Pulsar already has. StreamNative Cloud, which provides fully managed Pulsar services in the cloud, has a built-in Kafka protocol with enterprise features. It enables teams to take advantage of Pulsar’s distinct features such as multi-tenancy and tiered storage while continuing to use their existing Kafka applications.

Futureproof Kafka applications with Pulsar

The most important benefit of the Kafka protocol on StreamNative Cloud is that it allows organizations to harness the strengths of both systems without disrupting their legacy Kafka applications. With a unified event streaming platform, they can take advantage of the following features that Pulsar has to offer.

• Unified streaming and queuing
• Streamlined operations with enterprise-grade multi-tenancy 
• Enhanced scalability and elasticity with a rebalance-free architecture
• Infinite data retention with Apache BookKeeper and tiered storage 

Now, let’s take a closer look at each of them by understanding how Pulsar can help solve some of the key pain points for Kafka.

Unified streaming and queuing

Pulsar can be used to handle both real-time streaming scenarios like Kafka as well as traditional message queues like RabbitMQ or ActiveMQ. With the Kafka protocol on StreamNative Cloud, organizations maintaining multiple systems for different use cases can manage streaming and messaging semantics in a single platform.

This ability is embodied in Pulsar’s four subscription types (Exclusive, Shared, Failover, and Key_Shared) and selective acknowledgment of messages. The former defines how messages are sent to the consumers of a topic. As a single topic can have multiple different subscriptions, that topic can be used to serve both queueing and messaging use cases. The latter means that you can use Pulsar to acknowledge messages individually. This is where Kafka falls short as it only allows you to commit a batch of messages by a given offset (Pulsar supports cumulative acknowledgment as well).

Note that Pulsar’s protocol handler mechanism allows brokers to dynamically load