Miner
Follow through this section to start mining on the Aion ecosystem.
Mining
This section contains information about mining on the Aion network. Get get started quickly follow through these steps:

Create Aion Wallet:

Download Mining Solver:

Connect Miners to Aion Network:
About Mining
A miner runs your system to solve a difficult mathematical problem by guessing the input value of a hash function. The difficulty of the problem is determined by network difficulty, which adjusts itself based on the network hash rate. Miners that correctly solve these problems are rewarded with AION
. On average, someone is awarded once every 10 seconds.
This guide will take you through the setup of various modules. There are two types of miners that can work with the kernel:
External Miner
If you wish to mine native AION
coins, you will want to set up an external mining rig. It will connect your kernel to the network, and mine AION
coins on the mainnet. We have provided all the software needed to begin mining, and it will require you to follow two modules (while running the Aion node):
Each of the above modules will need to be run simultaneously.
Mining Algorithms
Aion leverages an enhanced Equihash algorithm for its Proof of Work (PoW).
Test Miner
Test miner does not mine on the public network, but rather on your local kernel. It could be used to test and run your own chain, as it has a shorter setup time and adequate functionality to mine for AION
on the Mastery Testnet. Mining tokens on the testnet is for development purposes only. AION
awarded on the testnet is not worth anything.
Aion Mining Protocols
The following sections discuss the mining protocols used by the Aion network.
Aion Equihash
The Aion proof of work (PoW) protocol is based on the Equihash algorithm: a memory hard PoW algorithm solving the Generalized Birthday Problem. The original Equihash algorithm developed by Alex Biryukov and Dmitry Khovratovich may be found here.
Memory hard problems feature several properties which make them ASIC resistant:
 Large memory usage (relative to CPU onchip memory). This forces the algorithm to access system memory resulting in memory bandwidth acting as the upper bound on algorithm run time.
 Ineffective CPU & memory tradeoff. Traditionally, CPU cycles and memory usage may be traded to offset one resource by another. Equihash is resistant to this type of trading by exponentially increasing CPU cycles when attempting to trade CPU cycles for memory usage.
Aion uses a modified version of the Equihash solver developed by John Tromp. The original version may be found here.
The core challenge of Equihash is to find a complete binary tree of 2
^{k} indices (X
values) such that the XOR
of the hashes of indices (along with block header and nonce) is equal to 0
. Additionally, the following conditions must be met:
 For each height subtree, the
XOR
of its2i
leaf hashes must start withi*n 0
bits.  The leftmost leaf of any left subtree is less than the leftmost leaf of the corresponding subtree.
This document serves as a migration and development guide detailing changes required to convert the Tromp solver to generate solutions to the Aion PoW protocol. This document assumes a working knowledge of the Equihash algorithm as well as the Tromp Equihash solver. The reference implementation has been purposely left in a simplified and rather verbose state, ensuring each algorithm step is clearly outlined.
Algorithmic Parameters
The Equihash algorithm takes two integers N
and K
. N
specifies the width in bits which must XOR
to 0
. K
specifies the number of steps in which the computation takes place.
In addition to Equihash algorithm parameters, a personalization parameter is added to Blake2b. The personalization parameters ensure the digests computed are unique to Aion. Given the same inputs to a nonAion Blake2b algorithm, the digests produced are guaranteed to be different.
The Aion implementation of the Equihash algorithm uses parameters N = 210
and K = 9
, increasing the computational difficulty of the Aion PoW as compared to popular existing Equihash implementations. One of the notable effects of changing to Equihash parameters is increased memory usage. At a minimum, the amount of memory has been more than doubled from 144 MB
to 300 MB
based on some set of experimental parameters, though the reference implementation uses over 500 MB
.
The personalization parameter adds an additional layer of security by ensuring unrelated hash computations both within and outside of the Aion kernel may not be used in the PoW process.
The personalization used in the current implementation is 16 bytes
equal to Aion0PoW + N + K**
, where N
and K
are integers in little endian byte order.
Equihash Solution Generation
The Tromp Equihash solver uses a twostage bucket sort during its solution generation process. The number of bits to be processed in each sort is defined by two variables: RESTBITS
and BUCKBITS
. The values of RESTBITS
and BUCKBITS
must sum to DIGITBITS
where . This document presents algorithm details where BUCKBITS = 14
and RESTBITS = 7
.
Following the Tromp solver, Equihash solver the Aion solver produces Equihash solutions by processing digests in K+1
steps. These steps may be broken up into 3 primary groups referred to as Digit X
.
Equihash Hash Generation
Digit 0
is responsible for generating the hashes and produce solution indices and to perform the first bucket sort based on the first BUCKBITS
.
Input to the Blake2b algorithm is as follows: H(x) = H(BlockHeader) + nonce + X
H(BlockHeader)
: A32 byte
hash of the current blocks block header (excluding nonce and solution) using default Blake2b settings with no personalization values.nonce
: a randomly generated32 byte
value.X
: Hash index.
Digit 0
0
When generating hashes a 64
byte hash is generated by the Blake2b hashing algorithm. Next the hashes are split into J
byte segments L bytes long where and . Calculations are performed using integer division. In the case of N=210
and K=9
, generated 64 byte
hashes are split into J=2
segments with each segment L=27 bytes
long.
Generated hashes are then sorted into buckets based on the first BUCKBIT
bits. The actual number of bytes stored is determined by examining the number of bytes remaining to be processed. Table 1 shows the number of bytes to be stored at each step, subsequent sections explain how the tables values are calculated.
Digits 1
through 8
1
through 8
Digits 1
through 8
perform largely the same function and are grouped together. Each step performs two functions. First, all pairs of hashes in each bucket are XOR
ed to calculate the next set of collisions over the next RESTBITS
. Next, the hashes must be stored in buckets for the following step. In order to calculate the bucket in which to store the hash for the next step, each pair of hashes is XOR
ed, the next bucket ID calculated based on the XOR
of the next BUCKBIT
bits.
Digit 9
9
Digit 9
is the final step in producing candidate Equihash solutions. First pairs with collisions on the last RESTBITS
are found. Next, collisions on the last DIGITBITS
of each pair are found, if the final set of DIGITBIT
collisions are found to be 0
a candidate solution has been found. Each candidate solution is then processed to ensure it meets all remaining Equihash conditions. As these conditions have not changed with the parameter change, they will not be covered in depth within this document. The steps to process candidate solutions are largely unchanged from the original Tromp solver, though hash byte lengths have changed the number of bytes processed in each validation step.
One minor change to the validation procedure is in the final step of verifying byte 27
. As only the leading 2
bits are included in the calculation bit, shift operations are used to isolate these bits while the remaining 6
bits are discarded.
Hash Processing
Each step must process of a portion of the hash; DIGITBITS
bits long. Due to the asymmetry in the processing of the 210,9 parameters, the bits to process in each step must be calculated individually. Figure 1 shows the bits to be processed at each step. The prevbo
parameter within the implementation tracks the starting byte to process at each step; thus following figure 1 the appropriate bitshift operations are applied to isolate and XOR DIGITBITS
at each step.
Hash Size
In order to reduce the total amount of memory used the Equihash solver attempts to minimize the number of bytes stored at each step, excluding bytes processed in previous steps. Stored hashes are reduced in chunks of 4 bytes
.
The number of bytes remaining to be processed is shown in table 1, the hash bytes values at may be calculated by subtracting the total number of bytes processed after that step from the total length of the hashed bytes.
Table 1
Digit  Hash bytes 

0  26 
1  23 
2  20 
3  18 
4  15 
5  13 
6  10 
7  7 
8  5 
9  0 
Solution Representation
As with existing Equihash implementations the format of the solutions generated is an array of 2
^{k} integers representing the indices of the solution hashes. Solutions are encoded using Integer to Bit String (I2BS) as with existing Equihash implementations however the increased size of the solution index also results in an increase in the encoded solution size. Existing implementations use 21 bits
(2
^{k+1} possible index values) when representing each solution index saving 11
bits at each encoded integer ultimately resulting in an encoded size of 1344 bytes
. The Aion implementation also uses the I2BS encoding, however, 22 bits
must be used to represent each integer, saving 10 bits
per integer and resulting in an encoded solution size of 1408 bytes
. The actual conversion process follows the existing Equihash solution conversion process and is not covered in detail within this document.
Summary of Values
N = 210
K = 9
Personalization: "Aion0PoW" + N + K (N & K in little endian byte order)
DIGITBITS = 21
BUCKBITS = 14
RESTBITS = 7
Header Length = 496 bytes
Nonce Length = 32 bytes (Little endian byte order)
Encoded Solution size: 1408 bytes
Aion Stratum Protocol
In order to support the Aion PoW algorithm the stratum protocol definition has been modified to fit Aion. This document describes protocol version 1 which will be the first stratum standard supported by Aion.
Specifications
A handshake occurs after a TCP connection is established from a miner to the pool. The miner starts the handshake with the following:
{
"id": 1,
"method": "mining.subscribe",
"params": [
“MinerName/Version, “ProtocolVersion”
]
}
The server may choose to drop the client at this point if it does not support the given protocol version. Server replies back with the session id
and extraNonce
value:
{
“id”: 1,
“result”: [
“sessionId”,
“extraNonce”
]
“extraNonce”
}
The miner must then authorize with the following message:
{
“id”: 2,
“mining.authorize”,
“params”:[
“workerName”
“password” (Optional)
]
}
Once validation a miners subscription request a server may reply with a set_difficulty
message if the server supports varDiff
mining. Otherwise, the server may reply immediately with a mining.notify
message.
{
“id”: null,
“method”: “mining.notify”,
“params” : [
“jobId”,
“true”,
“target”,
“headerHash”
]
}
Parameters:
 Job ID in hex
 Clean job, may be set to false to allow miners currently mining this block to continue without interruption. If true, instructs miners to drop the current job and begin work on the new job.
 64 character hex string target for the current job.
 Hash of the header, used as input to the Equi2109 algorithm as well as block identification in the Aion kernel.
Clients submit jobs by sending:
{
“id”: “messageId”,
“method”: “mining.submit”,
“params”: [
“workerId”,
“jobId”,
“nTime”,
“extraNonce2”,
“solution”
]
}
Parameters:
 Worker Id to which to assign the share
 Original job ID
 Submit timestamp
 Client generated extraNonce value
 Calculated Equihash solution
Updated almost 5 years ago