---
title: "Challenge #3e: Efficient Broadcast, Part II"
---

# Challenge #3e: Efficient Broadcast, Part II

In this challenge, we’ll make our [Efficient, Multi-Node Broadcast](https://fly.io/dist-sys/3d) implementation even more efficient. Why settle for a fast distributed system when you could always make faster?

## Specification

With the same node count of `25` and a message delay of `100ms`, your challenge is to achieve the following performance metrics:

- Messages-per-operation is below `20`
- Median latency is below `1 second`
- Maximum latency is below `2 seconds`

## Evaluation

Build your Go binary as `maelstrom-broadcast` and run it against Maelstrom with the same command as before:

```
./maelstrom test -w broadcast --bin ~/go/bin/maelstrom-broadcast --node-count 25 --time-limit 20 --rate 100 --latency 100
```

On success, congratulations, you’ve completed the Broadcast challenge. Move on to the [Grow-Only Counter challenge](https://fly.io/dist-sys/4). If you’re having trouble, poke your head in at [Fly.io Community forum](https://community.fly.io/) and ask for some help.

1. **Echo**
   Get the hang of working with Maelstrom in Go by creating a node which is a binary that receives JSON messages
   
   [Read More About Echo](https://fly.io/dist-sys/1)
2. **Unique ID Generation**
   Implement a globally-unique ID generation system that runs against Maelstrom's unique-ids workload
   
   [Read More About Unique ID Generation](https://fly.io/dist-sys/2)
3. **Broadcast**
   Implement a broadcast system that gossips messages between all nodes in the cluster. Gossiping is a common way
   
   [Read More About Broadcast](https://fly.io/dist-sys/3a)
4. **Grow-Only Counter**
   Implement a stateless, grow-only counter which will run against Maelstrom's g-counter workload. This
   
   [Read More About Grow-Only Counter](https://fly.io/dist-sys/4)
5. **Kafka-Style Log**
   Implement a replicated log service similar to Kafka. Replicated logs are often used as a message bus or
   
   [Read More About Kafka-Style Log](https://fly.io/dist-sys/5a)
6. **Totally-Available Transactions**
   Implement a key/value store which implements transactions. These transactions contain micro-operations
   
   [Read More About Totally-Available Transactions](https://fly.io/dist-sys/6a)