Solana SWQoS Endpoint Documentation

What is the SWQoS Endpoint?

The SWQoS Endpoint provided by ERPC is a high-performance RPC service that allows users with stake connections to send transactions through dedicated lanes.
It is available for both shared and dedicated plans, enabling faster and more reliable transaction delivery.
The endpoint can be obtained by registering your elSOL holdings on the ERPC Web Dashboard.

What is SWQoS?

SWQoS (Stake weighted Quality of Service) is a communication control mechanism that prioritizes validators with stake connections.
Leaders allocate approximately 80% of total bandwidth to the priority lane and 20% to the non-priority lane.
Traffic with stake connections can utilize the priority lane while also being sent through the non-priority lane at the same time. As a result, compared to traffic that relies solely on the non-priority lane, the effective delivery capacity is significantly larger.
This control is applied before Priority fee handling, at the stage where traffic is accepted and routed toward the leader, meaning that whether a transaction reaches the priority lane directly affects downstream processing speed.

Relationship with Priority Fee

Priority fee plays an important role, but it is applied after a transaction has reached the leader via SWQoS routing.
If a transaction cannot enter the SWQoS priority lane, the effectiveness of Priority fees becomes limited, and improving basic reachability is difficult.
For optimal operation, it is most effective to combine SWQoS-based reachability with appropriate Priority fee settings.

Shift in Cost Structure

In conventional transaction submission services, users were required to attach Tips when sending transactions.
With ERPC’s SWQoS Endpoint, Tips are not required. Instead, access to priority bandwidth is granted through holding elSOL.
elSOL is a Liquid Staking Token (LST) on Solana, issued by staking SOL.
Its exchange rate against SOL reflects accumulated staking rewards and is not fixed at a 1:1 ratio.
elSOL can be converted back to SOL through the unstaking process, with settlement reflecting accumulated staking rewards.
The SOL staked via elSOL is delegated to validators connected to ERPC.
As elSOL holdings increase, the total SWQoS bandwidth available across ERPC expands.
By holding elSOL, users contribute directly to strengthening the network and, in return, gain access to dedicated transmission lanes.

Bandwidth Allocation (TPS Structure)

For shared SWQoS Endpoints, eligible users receive 1 TPS for every 4.2 elSOL held, rounded down. For example, holding 10 elSOL in the connected wallet grants 2 TPS.
The actual available TPS is determined by the lower of the ERPC plan maximum and the elSOL-based allocation.
Eligible ERPC shared plans, including Developer Plan+ and Bundle Plans, can use the shared SWQoS allocation after the dashboard verifies the wallet holding elSOL.
For dedicated RPC nodes, SWQoS is available as a +€100/month option that assigns a 1,000 SOL staking allocation to the dedicated node.
Setup and verification are handled in the ERPC Dashboard: https://dashboard.erpc.global

Connection Keep Warming (Keep Alive)

With ERPC’s Solana SWQoS endpoint, sending a GET request to /ping allows you to maintain the HTTPS connection between the client and the ERPC SWQoS endpoint.
When submitting a transaction, the first request incurs a small amount of time for HTTPS and TLS session establishment.
By sending /ping in advance and keeping this connection active, you can avoid initial connection latency and enter the transaction submission process immediately when sending the actual transaction.
Even if transactions are not sent continuously, this approach is effective for setups where transactions must be sent quickly at specific moments, helping to stabilize initial submission behavior.

Ping Endpoint

Keep Warming is performed by sending a GET request to /ping on the SWQoS endpoint.
This request does not process any transactions and is used solely to maintain the connection state between the client and ERPC.

Endpoint Format (HTTPS)

text
https://<your-swqos-endpoint-domain>/ping
Replace <your-swqos-endpoint-domain> with the SWQoS-specific domain provided by ERPC.

Usage Example

Periodic Keep Alive Example (JavaScript)

typescript
async function keepWarm(endpoint: string) {
  try {
    await fetch(`${endpoint}/ping`, { method: 'GET' })
  } catch {
    // Ignore failures
  }
}

setInterval(() => {
  keepWarm('https://<your-swqos-endpoint-domain>')
}, 30000)
By sending /ping at regular intervals, you can maintain a state where transaction submission can begin immediately when required.

Notes

/ping does not consume TPS or affect elSOL-based bandwidth calculations ・It is not a substitute for transaction submission ・It is a supplemental request used solely to maintain the client-to-ERPC connection
The design of SWQoS (stake-based routing) and Priority fees remains unchanged. Use Keep Warming as a mechanism to reduce latency at the moment transaction submission begins.