Bitparking bitcoin merged mining pool

The bitparking merged mining pool allows you to merge mine for a number of different bitcoin-derived virtual currencies. The pool provides the Pay Per Share (PPS) method for the alternate merge mined coins and the Double Geometric Method at a 1.5% fee for the bitcoin portion of the reward. The supported alternate coins and their PPS payouts are:

Round Information

News

2013-05-25: The pool has suffered a block index corruption on the merge mining server. Merge mining is currently disabled until this is fixed. Once a new blockchain download is completed on the merge mining server it will be re-enabled.

2013-05-17: Addresses changes will no longer be made from 2013-05-20. If you need an address chaned due to the Vircurex hack you will need to get in touch before then. Changes required after then will have to involve contacting Vircurex and liasing with them to recover funds. This cutoff time is due to pool changes coming up involving automatic payouts.

2013-05-14: If you have registered addresses with the pool that belong to the Vircurex exchange you need to be aware that Vircurex have recently reset all their deposit addresses. If you have withdrawn funds you will need to get in touch with Vircurex to recover your funds. If you need to change your addresses for this one time you can email admin@bitparking.com for information. I highly recommend you do not use an address where you do not own the private key for registering addresses. Remember that the owner of that address ultimately owns the funds - make sure that's you!

2013-05-06: Are you wondering how much extra income the merge mine coins are worth in terms of BTC? The "!exchange" command in the #mmpool irc channel on freenode gives as of exchange rates right now:

That's like mining with a negative fee. Bitparking pays you to mine.

2013-05-03: After much discussion I've decided to retire the PPS portion of the pool. It's been off for a day now since the attempted pool server hack and DGM seems to be running smoothly. The pool doesn't have the reserves to continue PPS. I'll consider re-enabling it if or when the pool reserves are back at the correct level to operate it. The "Pool Changes" section below has been updated to reflect this fact. Note that the alternate chains continue to operate on a PPS basis, it's only the bitcoin rewards that are affected.

2013-05-02: By popular request there is now a discussion and support channel on the freenode irc network. Join the channel #mmpool.

2013-05-01: Please read this post on bitcointalk which outlines an attempt that was made to hack the pool server this morning. The PPS servers remain down and are redirected to the DGM servers while I keep the hot wallet on the pool as low as possible until I've audited the pool data.

2013-02-14: The pool now has Stratum protocol support. Stratum is a more efficient protocol than the current getwork and longpoller system. Newer mining programs such as cgminer support Stratum in their recent releases. Your miner should automatically switch to Stratum if it supports it or you can point it to stratum+tcp://mmpool.bitparking.com:3333 to connect directly. This should result in fewer stales and less bandwidth usage. The difficulty for mining on Stratum defaults to 16 but can be changed as below.

Difficulty can be adjusted per userid by setting your password to "d=xxx" where "xxx" is an integer number. So to mine at difficulty level '32' use "d=32". All miners using the same userid must use the same difficulty setting. This combined with stratum support should allow large hashrate miners to mine efficiently at this pool.

A page with some pool mining stats is here. See this forum post for more details about the stats.

Fees occasionally get adjusted for each chain based on monitoring of number of orphans and stales. Any changes to the fees are posted here.

Register

Register your alternate chain addresses to start mining.

Check Balance and Withdraw

Statistics

Servers

• DGM (1.5% fee): stratum+tcp://mmpool.bitparking.com:3333
• DGM (1.5% fee): http://mmpool.bitparking.com:15098

Connect

1. Use any standard bitcoin miner, either CPU or GPU based.
2. Register a userid associated with addresses for the coin chains you want to mine. Use that userid and any password in the miner. Withdrawals can only be made to the addresses you register so make sure they are correct!
3. User the protocol, server and port for the reward method you want to mine with from the "Servers" section above.
4. Statistics and Withdrawals for miners are available by putting your userid in the form above.

Examples

• cgminer
• Stratum at difficulty 8: ./cgminer -o stratum+tcp://mmpool.bitparking.com:3333 -u myuserid -p d=8
• Getwork at difficulty 2: ./cgminer -o http://mmpool.bitparking.com:15098 -u myuserid -p d=2
• Getwork at default difficulty: ./cgminer -o http://mmpool.bitparking.com:15098 -u myuserid -p anything
• m0mchil's miner (poclbm)
• poclbm.py -d 0 --user myuserid --pass anything --host mmpool.bitparking.com --port 15098
• puddinpop's OpenCL/CUDA GPU miner
• rpcminer-opencl.exe -url=http://mmpool.bitparking.com:15098 -user=myuserid -password=anything
• jgarzik's cpuminer (minerd)
• minerd --userpass myuserid:anything --url http://mmpool.bitparking.com:15098
• phoenix miner
• phoenix.exe -u http://myuserid:anything@mmpool.bitparking.com:15098/ -k poclbm VECTORS BFI_INT AGGRESSION=10 WORKSIZE=128 DEVICE=0 FASTLOOP=false

Pool Changes

2013-05-03: The stratum2 backup server has been retired due to network issues. The DGM specific servers on port 4333 have also been retired. Network redirections are in effect to transfer miners on those servers to the current stratum server on port 3333.

2013-05-02: The PPS reward system for the Bitcoin side of the rewards has been retired. Reward payments for bitcoins going forward will use the Double Geometric Method reward system. The getwork and stratum server have been switched over to using the DGM method.

Some features to note of DGM:

• Your earnings work like a capacitor. When you start mining it needs to charge so initial earnings are lower than expected. When fully charged they reach a normal level of earning. When you stop mining you continue to receive earnings until it is discharged. The end result should be equivalent to PPS with a 1.5% fee.
• Payments are made to your balance when a block is found. If the round is short you may get more than the PPS rate. If a series of long rounds occurs then your payments may be less than PPS. Overall it will average out
.
• The risk to the pool is much lower making it more likely to survive while balancing with low variance for miners. These parameters (more risk to pool, less to miners) can be tweaked and we can adjust it over time.
• At 1.5% fee you should earn more on DGM than PPS with consistent mining.
• The DGM server will continue to pay orphans as if they hadn't occurred. I'll need to monitor the orphan rate here to see if the fee needs to be adjusted for it.

The math behind the Double Geomtric Method is explained in this bitcointalk post.

The alternate coins that are merge mined will continue to be paid using PPS.

Discussion

The #mmpool irc channel on freenode is available for general discussion and support. A bitmessage psuedo mailing list is available at address BM-Bbwv13KAYh92ZJP2abkA1xhXEpYAevtQ. Any messages sent to that address will be broadcast to all subscribers so don't send anything private there. Subscribe to that address to see other users messages and send to that address to start a discussion or reply.

A BitcoinTalk forum thread is also available for discussion.

Contact

You can reach the bitparking admin at admin@bitparking.com. For encrypted/anonymous contact you can use bitmessage address BM-BbgTgGa6LX3yYqwJSwdwrzysvfWjM2u6. You can subscribe to that address for general announcements about bitparking sites.