RCon3 Tech Tidbit

Tech tidbit: COMM events

COMM events are RChain’s transactions. They are variable in size and differ from what many currently think of as blockchain transactions, such as a payment from one address to another on Ethereum. Such a transfer could take around 10 COMM events on RChain. As Greg Meredith puts it, a COMM event = database-like transaction.

RChain aims to support 40,000 COMM events per second when main net launches, which would require many shards. (RChain shards will be explained in a future tidbit.)

In the RCon3 interview above, Pyrofex CTO Mike Stay describes COMM events.

A COMM event is a delivery of a message from one process to another process. It’s the most fundamental operation that Rholang does…Contracts are processes that stick around and receive arbitrarily many messages. You can declare or deploy messages sent on one of these channels where there’s a contract listening on the other end. When you do a deployment of a message to a particular channel and there’s something listening there, it puts both of them together and then continues executing. This idea of taking a listener and the sender and joining them together, that is a COMM event. To transfer value from one purse to another one—a purse is one of these contracts that holds monetary value—costs about 10 COMM events.

RSong developer Kayvan Kazeminejad gives an example of the COMM events needed to use the RSong mobile app, which allows tokenized payments to all artists associated with a song when the song is played or purchased. The number of COMM events depends on the number of artists to be compensated.
RSong allows the user to listen to a song either in stereo or an immersive technology version. These are the COMM events associated with a user playing a song.

  1. Compute if the user has enough tokens to listen to the song
  2. Retrieve metadata that specifies the artist payment allocations
  3. Manage each wallet associated with the song (one per artist)
  4. Fetch the stereo version of the song
  5. Fetch the immersive version of the song
  6. Fetch the artwork for the song

Click here to download the RSong White Paper.