SHA-256 and Scrypt are the two most common algorithm systems used by cryptocurrency miners in order to authenticate blocks of transaction data. The system used, unfortunately, is not up to the miners; it's set by the developers of a given type of currency.
SHA-256 is the more complex of the two, and it's used by Bitcoin and most of the currencies based upon its code. Data block processing with SHA-256 tends to be slower—transaction turnaround times, as a result, are measured in minutes as opposed to seconds—but it's argued that it's also more thorough and leaves less room for error. Its advocates also say it's better for overall data security. Successful mining of coins using SHA-256 often requires hash rates at the gigahashes per second (GH/s) range or higher; this means it's generally more difficult for individual miners to use; those who do often employ an ASIC or some other separate computing device set up to perform only mining tasks. Since some miners can't devote a machine—or at least an ASIC—to the task of mining, they often join mining pools.
Scrypt is the quicker and more simple algorithm of the two, and as new digital currencies are being introduced, more of them are favoring it over SHA-256. Scrypt is much easier to run on an already-existing CPU, and tends to use up less energy than using SHA-256; as a result, it's favored by most individual miners. In comparison to SHA-256, Scrypt's hash rates for successful coin mining generally range in the kilohashes per second (KH/s) or megahashes per second (MH/s) areas of difficulty, which can be achieved with regular computers without the need of ASICs or other hardware. Some argue this simpler system is more susceptible to security issues, since fast transaction turnaround times can mean the system is taking a less thorough look at the data. Its advocates point out, however, that hasn't as of yet presented a real-world problem.
Proof-of-Work Mining. This is exactly what it sounds like: you earn coin and transaction fee rewards according to the number of blocks you mine successfully. Once a miner or miners has completed the satisfactory mining of a data block, they earn a number of coins, a share of the transaction fees contained within that block, or a combination of the two. This type of mining requires an investor to take an active part in mining data blocks, which helps verify transaction data and create new coins. With proof-of-work mining, if you don't put in the effort to mine, you won't earn anything extra.
Proof-of-Stake Mining. In the truest sense of the word, this isn't actually “mining” per se, since there isn't any additional work required on the part of the investor. All you have to do to earn with this method is to hold coins in a given type of digital currency. Your earnings are based upon the number of coins, or “stake,” you hold. The more you invest, the more you are likely to earn. The advocates of this method like to point out that it provides for higher currency security, for those who invest more heavily are more likely inspired to see it succeed. This method is very rarely used alone, for it doesn't provide for any actual mining to take place.
There other hash solutions out there the best known of these being Scrypt-Jane and Adaptive-N which for the most part are the same. They both use a variable N factor which is locked to 2^10 in Scrypt. This is the memory requirement, 2^10 works out to 1024 bytes. Vertcoin a very popular Adaptive-N coin currently uses an N factor of 2^11 which works out to 2048 bytes, every time the N factor goes up the performance of miners drops by half. Vertcoin currently has half the performance of Scrypt and has a maximum N of 2^32 which works out to 4GB, most graphic cards cannot even do work at that level and with the current hash rate the difficulty of Vertcoin could not go low enough to support that level of N. Scrypt-Jane and Adaptive-N may be ASIC hostile but they are also GPU hostile.
There is an alternative that has been largly over looked which was created by Even Duffield. This is the chap who created DarkCoin which looks to include the DarkSend feature that will allow anonymous transactions. X11 uses 11 well known and high performing hashing solutions chained together to generate the hashes required to generate new blocks. Since it uses 11 different hashes it is complex and unlikely to see a ASIC for it any time soon. The good news for miners is that they can use X11 right now to avoid multipools and start gathering coins that are going to become very important when the Scrypt ASICs hit. Mining X11 gives 3-4 times the hash power of Scrypt, uses less energy and generates more heat. This is the solution that people have been looking for.
There is also Hirocoin that has launched recently and adopted X11 as its hashing solution. Hirocoin does not have the DarkSend feature but has been meticulously coded and fully featured on launch including DNS seed and binaries for different platforms. DarkCoin uses an inverse difficulty reward which means that the higher the difficulty the lower the reward. More miners means less coins, Hirocoin is more conventional in that it has 400 coins a block and is likely to be the first choice for miners.
I hope this information must help you a lot.
Thank you for you clarification, but Vertcoin is not GPU hostile, Vertcoin is GPU friendly.
According to schedule, it will require GPU to have memory per thread equal 4 GB in 15 Jul 2694, I don't think at that time 4 GB for GPU will be a problem.
33554432 | 4 GB | 22864142697 | Sun, 15 Jul 2694 06:44:57 GMT |
Here is Dogecoin about X11
http://www.reddit.com/r/dogecoin/comments/23fk2i/very_long_very_serious_development_summary_week/
