Stratum V2 Solo Mining — The Complete 2026 Guide

For fourteen years, every miner on Earth spoke the same protocol: Stratum V1, unencrypted JSON over plain TCP, written in 2012. Stratum V2 replaced it on paper in 2019 — but it took until 2026 for the pieces to arrive together: firmware that speaks it, pools that serve it, and hardware cheap enough that ordinary people run it at home. This guide is the practical map of that landscape. What the protocol does, which machines and firmware support it today (with several widely-repeated claims corrected), how to configure your miner in a few minutes, and how to confirm you are really on V2 rather than silently falling back.

Key takeaways

• V2 is software, not hardware. A 2024 Bitaxe and a 2021 Antminer S19 both speak it — the ASIC never changes, only the firmware.
• Only three firmware families support it natively: Braiins OS+ on Antminers, AxeOS on Bitaxe, and the NerdQAxe firmware. Stock Bitmain, stock WhatsMiner, VNish and LuxOS are all V1-only, despite what several older guides claim.
• Encryption is the benefit that reaches every miner. V1 sends your wallet address and shares in plaintext; V2 wraps everything in Noise-protocol encryption, ending hashrate hijacking as a category of attack.
• Adoption crossed its tipping point in 2026: from an estimated 15–20% of hashrate early in the year to seven major pools — close to 75% of the network — committing on 7 May, with the reference implementation’s working group projecting 40–60% of hashrate on V2 by year’s end.
• Solo mining changes the calculus. V2’s famous job declaration matters most where a pool controls block content and custody. A non-custodial solo pool never did — so for solo miners the wins are encryption, latency, and verification.
• Verification is the underrated feature. With V2 and coinbase decoding, your miner shows you the block’s outputs before you hash them. You stop trusting the pool and start checking it.

What Stratum V2 actually is

Stratum is the conversation between your miner and the pool. The pool says here is a block header, try nonces; the miner hashes and answers here is one that met the target. That exchange happens millions of times a day across every ASIC on the network, and until recently it happened in the clear.

Stratum V2 rewrites that conversation on three axes at once.

1. Encryption, built in

Every V2 session is encrypted end-to-end with the Noise protocol framework — the same cryptographic foundation as WireGuard. Before any mining work flows, the miner and pool complete an authenticated Diffie-Hellman handshake, and from that point every message is sealed with ChaCha20-Poly1305 authenticated encryption (AEAD, per the protocol security specification) — meaning tampering is detected, not just eavesdropping prevented.

This is not TLS bolted onto a plaintext protocol — the difference is explained in our TLS stratum guide. There is no separate encrypted port, no certificate to install, no toggle to remember. If you are on V2, you are encrypted. That single design decision closes off hashrate hijacking: on V1, anyone controlling a segment of the network path between you and your pool can silently redirect a slice of your shares to a pool of their own. Braiins documented suspected cases across several countries, and independent research published by Hashlabs in 2025 confirmed it as an active attack in production environments, with typical losses up to 2% of a facility’s hashrate before detection — enough to matter, small enough to miss. On V2 it is not difficult to detect. It is cryptographically impossible.

Home miners on residential connections, shared networks, or behind ISP equipment they do not control benefit most from this. Which is to say: exactly the people running a Bitaxe on a desk.

2. A binary wire format

V1 speaks JSON, which is wonderfully readable and wasteful on the wire — field names, quotes and whitespace add roughly a third of overhead versus a compact binary equivalent. V2 replaces it with fixed-layout binary frames: smaller messages, faster parsing, less CPU on both ends.

For a thousand-rig farm that is a real infrastructure line item. For a single home miner the payoff is subtler but still real: jobs arrive marginally faster after a new block, which means fewer seconds spent hashing work that is already stale.

3. Job declaration

This is the part that makes V2 historically significant. Under V1 the pool builds the block template and the miner hashes whatever arrives — so the pool chooses which transactions enter the block. With roughly five pools controlling about 70% of hashpower, a handful of operators effectively decide the contents of most Bitcoin blocks.

V2’s Job Declaration Protocol lets a miner run their own Bitcoin node, build their own template, and propose it to the pool. The pool’s role shrinks from decision-maker to share aggregator and proof-of-work validator.

An honest note for solo miners: job declaration is the answer to a problem solo mining never had. When you mine solo on a non-custodial pool, the block reward is paid by the network’s coinbase directly to your address — the pool never holds your funds and never stands between you and the reward. Job declaration would let you also choose the transactions, which is a genuine sovereignty gain, but it is an addition to an already-decentralised arrangement rather than a fix for a broken one. The features that change your day-to-day are encryption, latency, and verification.

Stratum V1 vs Stratum V2 at a glance

Which firmware supports Stratum V2 in 2026

This is where most guides — including our own earlier article — got it wrong, and where it costs you an evening if you take the wrong claim at face value. Here is the verified state as of August 2026.

Two corrections worth stating plainly, because both circulate widely:

• No Antminer ships with Stratum V2 in stock firmware — not the S21, not the S23. You need Braiins OS+. Some stock builds expose a V2-looking setting that never negotiates a real V2 session, which is worse than not offering it at all, because the miner appears configured while quietly running V1.
• Bitaxe and NerdQAxe do support V2 natively, and have since June 2026. Guides written before then say otherwise; they are simply out of date.

Read the first correction from the other direction and it becomes the most important row in the table: Braiins OS+ is what brings the world’s most deployed ASIC family onto Stratum V2. Every Antminer from the S9 to the S21 XP becomes a V2 machine the day it is reflashed — encrypted transport, authority-key authentication, the full protocol. For the millions of Antminers in the field, the path to V2 is not a new machine; it is one firmware flash. That is why this guide treats Braiins OS+ as a first-class configuration target, and why the Start wizard generates Braiins-ready V2 URLs alongside the AxeOS and NerdQAxe formats.

Why Bitaxe got V2 before the industrial machines

There is a neat piece of open-source history here. The V2 implementation in ESP-Miner — the firmware behind AxeOS — was contributed by warioishere, who also wrote the V2 implementation for the NerdQAxe firmware, and is the author of Blitzpool, the first solo pool to run Stratum V2. Client and server were built by the same hands, tested against each other.

The practical consequence is that Bitaxe-class hardware has unusually solid V2 support: it was not retrofitted, it was co-designed. That is also why SoloFury’s V2 stack — which runs the same open-source pool software — works with these devices out of the box.

If your firmware is V1-only: the Translation Proxy

The Stratum V2 Reference Implementation ships a Translation Proxy that runs on your own network. Your V1 miner connects to the proxy; the proxy speaks V2 to the pool. You get the encryption and the binary efficiency without touching your firmware.

What you do not get is job declaration, which requires a native V2 client. For most home setups the proxy is more moving parts than it is worth — but for a farm of V1 machines that cannot be reflashed, it is a legitimate bridge.

Which pools support Stratum V2 in 2026

V2 spent years as a standard almost nobody served — an estimated 15–20% of network hashrate connected over it in early 2026, mostly for the encryption. That changed on 7 May 2026, when seven of the largest pools — together close to 75% of global hashrate — joined the Stratum V2 Working Group. Bitcoin Core itself added experimental V2 support in v30, and the reference implementation’s working group projects V2 becoming the default protocol in new ASIC firmware shipments by the end of 2026, reaching 40–60% of network hashrate.

Joining a working group is a starting line, not a finish. Here is who actually serves V2 connections today, August 2026.

The solo picture deserves its own sentence. The Stratum V2 project’s ecosystem page lists the solo pools serving V2 in production, and it is a short list next to the hundreds of V1 endpoints the solo world runs on. The reason is structural rather than reluctance: most of the solo ecosystem was built on stratum server software that predates the protocol by a decade, and retrofitting an encrypted binary protocol onto a codebase from 2012 is a rewrite, not a patch. The solo pools serving V2 today are the ones built on newer software — a short list, and one we are glad to be on.

How SoloFury runs Stratum V2

SoloFury has served Stratum V2 in production since August 2026, across nine regions on five continents — the same regional endpoints that have always served V1, with no separate V2 hostname to remember.

The stack, briefly

Behind each endpoint, the pool software talks to a Bitcoin Core 31.1 node through the IPC mining interface — a Cap’n Proto socket that hands block templates to the pool the moment the chain tip or mempool fees move, rather than on a polling interval. The pool software is open source, and the V2 layer is the Stratum V2 Reference Implementation’s own codec, not a proprietary reimplementation. Anyone can read the code their hashrate talks to.

Encryption is genuinely end-to-end: the Noise session runs between your miner’s firmware and the pool software. No network equipment along the route — SoloFury’s or anyone else’s — can read or alter your traffic, and an endpoint that cannot prove the authority key fails the handshake before a single share is sent.

V1 and V2 on the same port

Both protocols are served on port 3333, with a second port, 3343, for high-difficulty machines. The pool detects which protocol your miner speaks and responds accordingly — you do not need a different endpoint for V2, and a mixed fleet of V1 and V2 miners can point at the same address.

What the authority public key is for

That long base58 string is SoloFury’s authority public key, and it is the piece of V2 that people most often skip. Your miner uses it to verify, cryptographically, that the endpoint answering on port 3333 is really SoloFury and not someone who has intercepted your DNS or your route.

It is the same trust model as an SSH host key. Without it your miner would connect to whoever answers; with it, an impostor fails the handshake and your hashrate never leaves the building. Pin it, and hashrate hijacking stops being something you have to worry about.

The trap almost nobody documents: encryption without authentication. In the AxeOS implementation, authority key verification is optional — leave the field empty and the miner still connects, in what the code calls TOFU mode (trust on first use). The session is encrypted, the dashboard looks identical, and you have silently skipped the one check that proves who is on the other end. Two habits close the gap: always paste the authority public key, and on AxeOS 2.15.0 or later enable the per-pool Require authentication option, which makes the miner refuse any endpoint that cannot prove the key rather than falling back to trust.

Why BTC only

SoloFury’s V2 stack talks to the node through Bitcoin Core’s IPC mining interface. No other SHA-256 chain implementation currently exposes an equivalent — not Bitcoin Cash Node, not Bitcoin ABC, not the BC2 or BCH2 daemons. Until they do, BCH, BC2, BCH2 and XEC remain on Stratum V1, with full version-rolling and AsicBoost support, on their existing ports.

This matters for hardware selection. A Bitaxe pointed at BTC over V2 has the encryption and verification benefits; the same Bitaxe pointed at BCH2 for better block odds runs V1. Both are legitimate choices — see our solo mining guide for how to think about the trade-off between protocol features and realistic odds.

Configuring your miner for Stratum V2

The setup differs by firmware, because the three implementations expose the settings differently. The fastest route for any of them is the SoloFury Start wizard, which supports all three V2 firmware families — AxeOS, NerdQAxe and Braiins OS+ — picks your nearest region by measured latency, generates the exact strings in the format your firmware expects, and calculates the difficulty your hardware should ask for. What follows is the manual version.

AxeOS (Bitaxe) — separate fields

Open your miner’s web interface and go to Settings → Pool Configurations. AxeOS 2.14 and later give you individual fields rather than a single URL:

Stratum Host        eu-btc.solofury.com
Stratum Port        3333
Stratum Protocol    Stratum V2
User                bc1qYourAddress.bitaxe
Password            x
SV2 Channel Type    Extended
SV2 Authority Pubkey  9cLif4sCxvAz7FBP7GPvYG8Mv586ZhdgNbn3f4PsrM56gboSZEp
Require Auth        enabled  (2.15.0+)
Decode Coinbase Tx  enabled

Two settings deserve explanation. Channel type can be Extended or Standard: Extended sends you the coinbase template so your miner can verify it, Standard has the pool precompute more and sends only the header, which is lighter on an ESP32. Both work with SoloFury; Extended is what makes coinbase verification possible, so start there. Decode Coinbase Tx is what turns that data into something readable on your miner’s screen — leave it on.

Set a second pool as fallback while you are there, pointing at the V1 port (6060). The protocol coordinator handles every pairing — V2 primary with V1 fallback, V2 with V2, or the reverse — and while running on the fallback it keeps probing the primary with a heartbeat, switching back automatically the moment it answers. If anything about V2 misbehaves, your miner keeps hashing instead of sitting idle, and recovers without you touching it.

NerdQAxe firmware — same idea

The Nerd-series firmware shares its V2 implementation with AxeOS, written by the same developer, so the fields and behaviour match. Open the miner’s web interface, go to Settings → Pool, select Stratum V2, and enter the same host, port, user, password and authority public key as above. Firmware 1.0.37 or later is required, and primary and fallback pool can run different protocols — V2 primary with a V1 fallback is the recommended pairing.

Braiins OS+ — the key goes in the URL

Braiins takes a different approach: instead of a separate field, the authority public key is embedded in the URL path. This trips people up constantly, because a URL that looks correct fails silently without it.

stratum2+tcp://eu-btc.solofury.com:3333/9cLif4sCxvAz7FBP7GPvYG8Mv586ZhdgNbn3f4PsrM56gboSZEp

In the Braiins OS+ interface, go to Configuration → Pool Groups, set the protocol selector to Stratum V2, paste that URL, set the worker to address.workername, and save. An S21-class machine should use port 3343 rather than 3333, so the pool starts it at a difficulty appropriate to its hashrate. Rather than assembling the URL by hand, let the Start wizard emit it: select Antminer + Braiins OS+, and it outputs the complete stratum2+tcp:// string with the authority key already embedded and the right port for your machine’s class — which eliminates the missing-key mistake entirely.

Install Braiins OS+ 26.07 or later. Versions before 26.05.1 carry a known S21+ underperformance bug in warm conditions, and older builds use a deprecated form of one V2 channel message that can fail against current pool implementations.

Pick your region

Latency matters more in V2 than people expect — not because the protocol is fragile, but because faster job delivery means fewer stale shares, which is one of the places V2’s efficiency gain actually comes from. Use the endpoint nearest you:

How to verify you are really mining on V2

This section exists because of a specific failure mode: a V2 configuration that quietly falls back to V1 produces no error. Your miner connects, shares are accepted, the dashboard looks healthy — and you are on the protocol you were trying to leave. Three independent checks close that gap.

1. Ask your firmware

Every V2-capable firmware reports the negotiated protocol somewhere in its pool status. On AxeOS it appears as Mode: SV2 Extended Channel or similar on the miner’s info screen. On Braiins OS+ the pool status shows the protocol version. If it says V1 after you configured V2, the configuration did not take — usually a malformed URL, a missing authority key, or a firmware version too old.

2. Check the PROTOCOL column on your miner page

Open your SoloFury miner page with your address and look at the worker table. Each worker carries a PROTOCOL badge: grey for SV1, orange for SV2. The badge reflects how that specific session connected, so a mixed fleet shows both, worker by worker.

This is the check that requires nothing from you but a glance, and it settles the question from the pool’s side rather than the miner’s.

3. Read the coinbase from your own hardware

This is the one worth understanding properly, because it is the strongest guarantee in solo mining and almost nobody uses it.

With an Extended channel and coinbase decoding enabled, your miner receives the actual coinbase transaction template — the transaction that pays out the block reward — and can display its outputs. On a Bitaxe mining BTC on SoloFury, that looks like this:

Block Header
  Height       963788
  Scriptsig    SoloFury
  Value        3.14278556 BTC

Outputs
  bc1q68eg...vyd2ey      0.03142785 BTC     (1%)
  bc1qavkk...n0tlw9      3.11135771 BTC     (99%)

Read what that means. Your miner — not the pool’s dashboard, not a block explorer, not our word for it — is showing you that if this block is found, 99% of the reward is addressed to your wallet and 1% to the pool. Before a single hash is spent on it.

This is the argument for V2 in solo mining. Every solo pool tells you the reward goes to your address. With Stratum V2 and coinbase decoding, you no longer have to take anyone’s word for it — the proof arrives with the work, and your own hardware displays it. Trust becomes verification.

Troubleshooting

The connection drops or the handshake never completes

The V2 handshake messages are larger than V1’s, and on network paths with PPPoE, double NAT, or a VPN they can be fragmented or dropped where path MTU discovery is broken. If your session establishes intermittently or not at all, lower the miner’s network MTU to 1400. On Braiins OS+ this is editable in the network configuration; on other firmware it may require SSH access.

The firmware says V1 after you configured V2

Check, in order: the scheme is stratum2+tcp:// and not stratum+tcp://; the authority public key is present (in the URL path for Braiins, in its own field for AxeOS and NerdQAxe); the port is 3333 or 3343; the firmware meets the minimum version. A single wrong character in the public key fails the handshake, and some interfaces silently fall back rather than reporting it.

Extended channel fails to open

The V2 specification changed the OpenExtendedMiningChannel.Success message in early 2026, and firmware built against the older form can fail to parse the response. If Extended channels do not work, switch to Standard channels — you lose coinbase visibility but keep encryption and everything else — and update your firmware when a newer build is available.

Wi-Fi drops on a Bitaxe every few minutes

Not a V2 problem, but it surfaces during V2 setups often enough to earn a line: some consumer routers with the 2.4 GHz channel set to automatic and 20/40 MHz width cause beacon timeout disconnects on ESP32-based miners. Fix it at the router: pin the channel to 1, 6 or 11 and force 20 MHz width.

It connects even though you never entered the authority key

Not a malfunction — a nuance. AxeOS treats key verification as optional and falls back to trust-on-first-use when the field is empty, so the session establishes and encrypts normally. What you are missing is pool authentication: proof that the endpoint is who it claims. Paste the key from this page or the Start wizard, and on 2.15.0 or later turn on Require authentication for the pool so the shortcut is no longer available.

Shares are accepted but the difficulty seems wrong

Vardiff needs a few minutes to settle. If your miner is small and the initial difficulty is too high, it may take a while before the first share lands. Pinning difficulty with d=NNNN in the password field shortcuts this — the Start wizard calculates the right value for your hardware.

Should you switch?

An honest answer, because the marketing around V2 tends toward the breathless.

Switch if your firmware supports it natively and you mine BTC. The encryption is free, the latency is marginally better, and coinbase verification is a genuine capability you do not otherwise have. There is no downside for a supported device.

Do not bother if your machine runs stock Bitmain, stock WhatsMiner, VNish, or LuxOS. Reflashing a working miner solely to gain V2 is a real risk — a bad flash bricks hardware — for a modest gain. Braiins OS+ brings efficiency improvements that may justify it on their own; V2 is a bonus, not the reason.

You will hear a 7% profitability figure from Braiins’ own testing, attributed to faster template delivery, lower latency and improved fee capture. Treat it as a ceiling under favourable conditions, not a promise. The encryption slice only materialises if you were being hijacked in the first place; the fee-capture slice needs job declaration and your own node. Most miners will see low single digits, and solo miners chasing a full block should care more about the coin they point at than the protocol version.

Where this goes next

The direction of travel is not in doubt. Seven pools representing most of the network’s hashrate have committed to V2, the reference implementation’s working group expects it to become the default protocol in new ASIC firmware shipments, and AntPool’s parent company is Bitmain — which makes stock Antminer support a question of scheduling rather than intent. When that lands, V2 stops being a firmware enthusiast’s choice and becomes the default that millions of machines speak out of the box.

Solo mining will get there later than pooled mining, for a structural reason: much of the solo ecosystem runs on server software that predates the protocol, and an encrypted binary rewrite arrives slowly in decade-old codebases. The solo pools serving V2 today are the ones built on newer software — a short list, and one we are glad to be on.

What will not change is the part that matters most for people running a miner at home: the ability to look at your own hardware and see, in plain numbers, where the money goes. That is not a marketing feature. It is the difference between a system you trust and a system you check.