|Why it matters?|
Example pricing comparison: *
||$96.99 p/month||$452 p/month||
Our flexible packages ensure we deliver value to our customers who pay for what they use, and automatically benefit from volume discounts.See how much you can save
|Simple usage based pricing||
Ably's pricing is simple and transparent. You pay for the messages, peak active channels and peak connections you use for the month. You can either pay for what you've used at the end of the month, or reserve capacity in advance each month and benefit from a discount.
PubNub packages, like Ably's are also transparent - you pay for the resources you use. However, pricing is based on transactions which are classified into more than 40 different types, making it difficult to predict ongoing costs.See Ably's pricing calculator
|Global datacenters locations||14||14||
As we have datacenters globally, we can ensure that your users always experience the lowest possible latency by connecting to the closest datacenter, and have complete availability by connecting to alternative healthy datacenters when necessary.
PubNub has datacenters in EU Central, EU West, Asia Pacific, US West, US East, South America.Find out more about Ably's datacenters
|Latency based routing||
Both Ably and PubNub offer latency based routing that ensures users anywhere in the world connect to the closest datacenter available to them.Find out more about Ably's latency based DNS
|Binary encoded messages||
Encoding messages in binary format is faster. It reduces bandwidth to send and receive messages, and streamlines the processing time for clients and servers when encoding and decoding messages.
PubNub does not support binary encoded messages.Find out more about our binary protocol
|Redundancy and Reliability|
|Mesh architecture / no central point of failure / self-healing cluster||
The Ably platform is designed with no single point of failure and to be self-healing. All our customers benefit from their apps running on all of our datacenters providing resilience, reliability and low latencies globally.
PubNub's platform is also distributed.Find out more about Ably's mesh architecture
Ably's servers are located in over 14 datacenters covering 4 continents with each datacenter designed to operate as part of the global cluster when available, but operate autonomously when necessary.Find out where Ably's servers are located
|Data replicated in multiple regions||Partial||
Ably stores every message in at least two datacenters and separate geographical regions. This ensures that an outage in any datacenter or region cannot result in data loss.
PubNub only guarantees full data replication for their Pro (equivalent to our Enterprise) plans.Find out about Ably's message delivery guarantee
|QoS & message delivery guarantee||Partial||
Ably provides guaranteed message delivery and continuity across disconnections. Publishers only receive an ACK when data is persisted in two locations, and subscribers never lose data during brief disconnections as we maintain connection state for each client on our servers.
PubNub imposes a message queue limit of 100 messages so cannot guarantee that message recovery is possible and thus all subscribed clients will receive all published messages"Find out about Ably's QoS and message delivery guarantee
|100% uptime guarantee||
PubNub provides a 99.999% uptime SLA available for their Pro packages (equivalent to our Enterprise packages).Find out about Ably's 100% uptime guarantee
Ably's WebHooks provide a means to get messages, channel lifecycle and present events pushed to your servers over HTTP.
PubNub supports WebHooks if you request them manually through support, however they are limited to presence events and do not cover channel lifecycle eventsFind out more about WebHooks
|Serverless cloud function invocation||Partial||
Ably can trigger serverless functions on any third platforms such as Amazon Lambda, Microsoft Azure or Google Function.
Presence allows you to subscribe to events when users or devices enter or leave channels. This is a useful feature for collaborative apps, games and chat rooms.
In addition to the features that PubNub offer, Ably supports a configurable number of presence members. PubNub supports a default announcement of 20 members and a self-configurable maximum of 100 members per channel. Ably supports 200 by default and far more upon request.Find out more about Presence
Ably's message history feature provides a means for clients or servers to retrieve messages that were previously published on a channel.Find out more about our History API
|Realtime data firehose||
Stream your realtime data published within the Ably platform directly to another streaming or queueing service such as Amazon Kinesis, Apache Storm or Kafka.Find out more about our Reactor Firehose
|Reliable message ordering||
Ably ensures that messages are delivered to persistently connected subscribers in the order they were published on each channel.
PubNub does not provide these guarantees and recommends you manage ordering yourself.Find out more about reliable ordering
Both PubNub and Ably offer push notifications.Find out more about Push Notifications
|Message and worker queues||
Data published into Ably's realtime system can be moved into traditional message queues for realtime or batch processing.
PubNub does not offer any message queuing features or ways to distribute data using once-only pattern to your server workers. However, PubNub has recently launched Blocks which appears to be an alternative function-as-a-service approach.Find out more about our Queues
|Custom domain endpoint (CNAME)||
Ably supports custom domains for our Enterprise customers allowing them to connect to Ably using a CNAME such as "realtime.your-company.com".
PubNub only provides support for custom CNAME for non-TLS connections as they do not serve up custom certificates for customers.Find out more about our custom domains
|Client libraries and protocol support|
|Native client libraries for every popular platform||
Both Ably and PubNub offer a considerable range of client libraries for every popular platform.View our client library SDKs
|Ably protocol support||
Ably's realtime protocol provides an efficient means to reliably and efficiently publish and subscribe to realtime data.
PubNub supports their own protocol.See which libraries natively support the Ably protocol
|PubNub protocol support||
The Ably platform is designed to be protocol-agnostic and ensure protocol interoperability. We support PubNub's protocol and ensure interoperability with Ably's protocol and the other protocols we offer.Learn more about our Protocol Adapters
The Ably platform is designed to be protocol-agnostic and ensure protocol interoperability. Ably supports MQTT.
PubNub supports MQTT.Find out which protocols we support
|White-label browser library||
PubNub does not, as far as we are aware, offer white-label libraries.Find out about our white-label libraries
|Continuity and connection state recovery||Partial||
Ably provides continuity for clients that become disconnected for reasons such as going through a tunnel or changing networks. Ably stores the connection state for each client on its servers so that clients that reconnect within two minutes can resume their connection and receive all messages published whilst they were disconnected.
PubNub imposes a message backlog limit of 100 messages so cannot guarantee that message recovery is possible. Also, PubNub provides no indication as to whether you have recovered all messages or not which makes it very difficult for developers to build apps that rely on this feature.Find out more about connection state recovery
|1st class WebSocket support||
PubNub uses HTTP as the transport for their client libraries. A WebSocket compliant interface is provided in some libraries, however this is just a wrapper around an underlying HTTP transport.View our supported transports
|Fallback to Comet (XHR) and Long Polling for older browsers||
Whilst most modern devices support WebSockets, there are situations where the device or the network environment requires use of HTTP transports.View our supported transports
Both Ably and PubNub offer TLS connections ensuring that all data in transit is encrypted.Find out more about SSL/TLS
|Token based authentication||
Token based authentication ensures your private key is never shared and instead a short-lived token is used to authenticate.
Ably allows configurable policies and an identity to be embedded in a token ensuring you have complete control over what actions your users can perform such as limiting which channels they can subscribe or publish to.
PubNub offers an authentication scheme called PAM that allows granular permissions to be configured per client. These permissions are stored on PubNub's servers however which means it is your responsibility to keep a client's permissions in sync with PubNub at all times.Find out more about Ably's authentication
|JSON Web Token support||
Using JWT allows for easy integration with your existing authentication systems, along with ensuring your private key is never shared.
Ably allows for not only Ably Tokens to be embedded within JWTs, but also for JWTs to be signed by Ably API keys and used themselves for authentication.
PubNub does not support JWT.Find out more about using JWT with Ably
|Configurable private key permissions||
Ably provides support for private API keys with configurable permissions including restrictions on channels or operations.
PubNub does not support configurable permissions for keys.Find out more about API keys
|Configurable channel permissions||
Ably provides channel rules providing you with the flexibility to maintain control of your channels, such as requiring SSL/TLS or only identified authenticated clients on a channel.
PubNub too allows channel rules to be configured.Find out more about channel rules
|Encrypted message payloads||
Ably's AES encryption allows messages to be encrypted using the provided private key before they are published to Ably. As a result, messages are practically impossible intercept and view for anyone including Ably. For very sensitive data, this ensures you can safely use us knowing your payloads are always secure and opaque.
PubNub too provides AES encryption in its libraries.Find out more about Ably's encryption
|Other important stuff|
Unfortunately at Ably we've not had the time to create a theme tune. We're working hard to play catch-up to PubNub on this front :)See and hear PubNub's theme tune
* All information regarding our competitors was obtained on or before January 2016. It is therefore possible that some of this information may now be out of date. If you believe that any of this information is incorrect, please get in touch with us so that we can correct it immediately.