# Quota

# What is quota

In Ethereum, transactions have to compete with each other by specifying attractive gas price as transaction fee. The higher gas price the bigger chance the transaction has to be processed by the miner. This is a typical bidding model. In principle, the gap between supply and demand can be effectively balanced by price. However, because it is difficult for users to determine the current supply and demand before bidding, in addition to the impossibility of predicting other competitors, market failure could be caused often. Moreover, since all the competing bids are simply applied to transactions, no effective solution is implemented to allocate TPS resources among accounts. In Vite, a certain amount of quota is consumed when the user initiates a transaction, such as transfer, deploying smart contract, invoking smart contract method, issuing new token, registering SBP, retrieving mining rewards, voting or staking. Vite has designed a quota model to balance between resource supply and demand.

Users are able to acquire quota in two ways:

• Compute a when doing a transaction, or
• Stake a amount of in the account.

If the user only needs to send a transaction, he may calculate a to get a small amount of free quota on demand. If the user need send frequent transactions constantly, he should stake to get enough quota.

We recommend users to obtain quota by staking.

# Quota usage rules

Different transactions consume different amount of quota. In Vite TestNet, the quota required for various transaction types are as follows:

Transaction type	Quota consumed
Send a transaction without comment	21000
Receive a transaction	21000
Register SBP	62200
Update SBP registration	62200
Revoke SBP registration	83200
Retrieve mining rewards	238800
Vote	62000
Cancel voting	62000
Stake for quota	21000
Cancel staking	21000
Issue new token	83200
Retrieve issuance stake	83200

In addition, comment consumes additional quota - 4 quota for zero character and 68 quota for each non-zero character.

For example, given hex encoding is used, to send a transfer transaction with the comment of 0x0001 (having two characters in total while the first is zero and the second is non-zero). The consumed quota is:

# Quota calculation

Quotas are calculated by the following formula:

• : The current available quota of the account;
• : The quota cap of a single account, related to total system throughput and total number of accounts;
• : The difficulty computed by the account when sending a transaction;
• : The weight of the quota obtained by computing ;
• : The amount of staked by the account;
• : The waiting time before sending a transaction, equivalent to height different between the snapshot block that current transaction refers to and an older snapshot block that previous transaction refers to.
• : The weight of the quota obtained by staking.

In TestNet some are constants,

• = 1000000
• = 6.259419649e-10
• = 4.200627522e-24

For the convenience in actual calculation, only is calculated. The result is mapped into corresponding quota based on the following table:

		The maximum number of uncommented transactions can be sent in a snapshot	Approximately equivalent to how much is staked without computing	Approximately equivalent to how much is calculated without staking
0.0	0	0	0	0
	21000	1	10000	67108864
	42000	2	20009	134276096
	63000	3	30036	201564160
	84000	4	40089	269029376
	105000	5	50178	336736256
	126000	6	60312	404742144
	147000	7	70501	473120768
	168000	8	80754	541929472
	189000	9	91082	611241984
	210000	10	101495	681119744
	231000	11	112005	751652864
	252000	12	122623	822910976
	273000	13	133362	894976000
	294000	14	144235	967946240
	315000	15	155256	1041903616
	336000	16	166440	1116962816
	357000	17	177804	1193222144
	378000	18	189364	1270800384
	399000	19	201141	1349836800
	420000	20	213156	1430462464
	441000	21	225428	1512824832
	462000	22	237989	1597120512
	483000	23	250862	1683513344
	504000	24	264082	1772216320
	525000	25	277682	1863491584
	546000	26	291702	1957568512
	567000	27	306188	2054791168
	588000	28	321192	2155479040
	609000	29	336772	2260041728
	630000	30	353004	2368962560
	651000	31	369958	2482757632
	672000	32	387743	2602090496
	693000	33	406468	2727755776
	714000	34	426270	2860646400
	735000	35	447322	3001933824
	756000	36	469840	3153051648
	777000	37	494096	3315826688
	798000	38	520436	3492593664
	819000	39	549332	3686514688
	840000	40	581427	3901882368
	861000	41	617620	4144775168
	882000	42	659288	4424400896
	903000	43	708576	4755193856
	924000	44	769276	5162500096
	945000	45	848844	5696520192
	966000	46	965904	6482067456
	987000	47	1197301	8034975744

For example, without calculating , staking 10000 should meet a transaction rate of up to 1 and 2 rate can be reached by 20009 stake. Staking 10 and waiting 1000 snapshot blocks (about 16 minutes and 40 seconds) is also sufficient to send a transfer transaction without comment.

# Two ways of obtaining quota

# Stake

Users can obtain quota by sending a stake transaction to built-in contract. When the transaction is received and confirmed, the specified quota recipient account will be granted with the corresponding quota.

# Parameters

• Staking amount: The minimum staking amount is 10.
• Quota recipient address: The account who receives quota, could be the staking account itself or any other account since staking for other accounts is permitted.

The staked will be temporarily deducted from balance, and cannot be traded during staking period. The staking account can retrieve staked tokens after 259,200 snapshot blocks (about 3 days) by sending a cancel-staking transaction. After this transaction is received and confirmed, the corresponding quota in the quota recipient account won't exist any more.

# Computing PoW

The user can obtain an one-time quota by computing a upon transaction sending. According to the formula, the expected difficulty is 0x3FFFFFF for sending an uncommented transfer transaction without staking.

In the TestNet, we have built a pool, which provides the capability to obtain transaction quotas by calculating PoW in Vite official wallet.

# PoW formula

1. Convert to in following formula:

= 2**256 / (1 + 1/)

• : difficulty, 256-bit number, padding zeros at front when less than 256 bits;
• : target, 256-bit number, usually the first bit is 1.

For example, if = 0x3FFFFFF, then = 0xFFFFFFC000000000.

2. Calculate based on transaction data. is the proof of work. In calculation, a random number is continuously assigned to until the following conditions are met:

• : Hash function
• : User account address
• : Hash of previous account block

# FAQ

• Can I stake for multiple quota recipient addresses?

Yes. You need to send multiple staking transactions to different quota recipient addresses. Each staking can have different expiration.

• Can I stake for the same recipient multiple times?

Yes, the staking amount for this recipient will be accumulated. Staking expiration time = height of snapshot block referenced by the response block of last staking transaction + 259200.

• Can I have my , which was staked to a recipient address, be retrieved in multiple times?

Yes. After stake expires, staked can be retrieved in multiple times. Stake retrieval won't change the expiration time.

• Is a stake retrievable if it has not expired yet?

No. However, the stake can be retrieved at any time after it expires.

• Will the quota obtained by staking be used up?

Quota obtained through staking is related to staking amount and snapshot block height difference during the period in which no transaction has taken place, and continues to be effective as long as the staked is not retrieved. If the wallet shows your current quota is 0, it may increase after waiting for a while.

• Can a recipient accept quota staked from multiple staking addresses?

Yes. The received quota is the sum of the staking amount that has applied to this recipient address.

• Does receiving transaction consume quota?

Yes, an individual receiving transaction consumes 21,000 quota.

• How to receive the first transaction in a new account if I don't stake?

If you don't have to stake, you can calculate to get one-time quota instead.