Dao Bitcoin la gi?
Dao Bitcoin la qua trinh tao ra bitcoin moi va xac nhan cac giao dich tren mang Bitcoin. Cac tho dao su dung phan cung may tinh chuyen dung de giai cac bai toan tinh toan, va doi lai ho nhan duoc bitcoin lam phan thuong.
Moi giao dich Bitcoin phai duoc xac minh va ghi lai tren blockchain — so cai cong khai, phan tan cua Bitcoin. Dao la thu lam cho dieu nay tro nen kha thi. Khi ban gui bitcoin cho ai do, giao dich do duoc phat len mang va nhom lai voi cac giao dich dang cho khac thanh mot "khoi". Cac tho dao canh tranh de xac thuc khoi do bang cach tim ra loi giai cho mot cau do mat ma. Tho dao dau tien giai duoc se duoc them khoi vao blockchain va nhan duoc phan thuong khoi.
Qua trinh nay phuc vu hai chuc nang quan trong: no tao ra bitcoin moi theo mot lich trinh co the du doan va giam dan, va bao ve mang khoi gian lan. Vi dao doi hoi dau tu nang luong va phan cung thuc te, viec viet lai lich su giao dich hoac chi tieu kep se ton kem den muc cam cho bat ky ke tan cong nao.
Hay nghi ve cac tho dao nhu ke toan va bao ve an ninh cua mang Bitcoin, tat ca trong mot. Ho xac minh rang cac giao dich la hop phap, dam bao khong ai chi tieu cung mot bitcoin hai lan, va duy tri mot ban ghi bat bien cua moi giao dich tung duoc thuc hien.
Cach dao hoat dong
Ve co ban, dao Bitcoin bao gom viec lien tuc bang (hash) mot tieu de khoi bang thuat toan SHA-256 cho den khi ket qua dat duoc mot muc tieu cu the. Day la cach no hoat dong tung buoc:
Tieu de khoi va bam
Moi khoi ung vien co mot tieu de chua nhieu du lieu: bam cua khoi truoc, tom tat cua tat ca cac giao dich trong khoi (Merkle root), mot dau thoi gian, muc tieu do kho hien tai, va mot so goi la nonce.
Phan mem dao lay tieu de khoi nay va chay no qua hai vong bam SHA-256. Dau ra la mot so 256-bit — mot chuoi thap luc phan dai nhu:
93ef6f358fbb998c60802496863052290d4c63735b7fe5bdaac821de96a53a9a
Muc tieu va nonce
De mot khoi hop le, bam cua no phai nho hon muc tieu do kho hien tai. Neu muc tieu la:
0000000000000a3290f000000000000000000000000000000000000000000000
thi bam khoi phai bat dau voi du so khong dau de nho hon so do. Tho dao thay doi nonce (va cac truong khac) voi moi lan thu, tao ra mot bam hoan toan khac moi lan. Day ve co ban la mot tro choi doan bang luc luong — khong co loi tat nao de tim mot bam hop le.
Vi du ve xo so
Dao thuong duoc vi nhu xo so. Moi lan thu bam giong nhu mua mot ve so. Phan cung nhanh hon co the thu nhieu bam moi giay hon (hashrate cao hon), co nghia la nhieu ve hon va co hoi trung thuong tot hon. Nhung moi lan thu rieng le deu co cung xac suat thanh cong nho be, bat ke da co bao nhieu lan thu truoc do.
Khi mot tho dao tim thay mot bam hop le, ho phat khoi hoan chinh len mang. Cac nut khac xac minh no mot cach doc lap — kiem tra rang bam hop le, cac giao dich la hop phap, va cac quy tac duoc tuan thu. Sau khi duoc chap nhan, khoi duoc them vao chuoi va tho dao nhan phan thuong.
Phan cung dao
Phan cung dao Bitcoin da tien hoa manh me ke tu khi mang ra mat vao nam 2009. Moi the he mang den nhung cai tien lon ve toc do va hieu qua nang luong.
CPU (2009-2010)
Trong nhung ngay dau tien, Satoshi Nakamoto va nhung tho dao dau tien su dung bo xu ly may tinh thong thuong (CPU) de dao. Day la lua chon duy nhat vao thoi diem do, va no hoat dong vi do kho mang cuc ky thap. Ngay nay, dao CPU la hoan toan khong thuc te doi voi Bitcoin.
GPU (2010-2013)
Cac tho dao som phat hien ra rang cac don vi xu ly do hoa (GPU) — duoc thiet ke cho tinh toan song song — hieu qua hon nhieu trong viec bam SHA-256. Mot GPU don le co the cung cap hashrate gap 50-100 lan CPU trong khi su dung it nang luong hon cho moi lan bam. Cac card AMD, dac biet la Radeon HD 5870, da tro thanh tieu chuan cho viec dao.
FPGA (2011-2013)
Field Programmable Gate Arrays (FPGA) la buoc tiep theo. Mac du chung khong mang lai su tang toc do an tuong nhu GPU so voi CPU, chung tiet kiem nang luong hon dang ke. Mot tho dao FPGA dien hinh co the cung cap 826 MH/s o 80 watt, so voi 600 MH/s o 400 watt cho GPU. Su cai thien gap 5 lan ve hieu qua nang luong nay lan dau tien lam cho cac hoat dong dao lon tro nen kha thi ve mat kinh te.
ASIC (2013-hien tai)
Application-Specific Integrated Circuits (ASIC) la cac chip duoc thiet ke de lam mot viec duy nhat: dao Bitcoin. Chung khong the duoc lap trinh lai cho cac nhiem vu khac. Su chuyen mon hoa nay cho phep chung dat duoc hashrate khong lo voi muc tieu thu dien tuong doi thap.
ASIC dai dien cho ky nguyen hien tai va co the la cuoi cung cua su tien hoa phan cung dao. Khong giong nhu cac chuyen doi truoc (CPU, GPU, FPGA), khong co cong nghe nao khac biet co ban dang cho de thay the ASIC. Tien bo hien nay den tu nhung cai tien tung buoc — quy trinh che tao chip nho hon (5nm, 3nm) cai thien hieu qua nang luong.
Cac tho dao pho bien
Duoi day la mot so tho dao ASIC hien tai o cac quy mo khac nhau. Day la cac vi du, khong phai khuyen nghi — luon tu nghien cuu truoc khi mua. Hieu qua nang luong (J/TH) la yeu to quan trong nhat, vi dien la chi phi van hanh chinh.
Cac the o tren duoc sap xep gon theo quy mo — tu Bitaxe chay bang USB ban co the dat tren ban lam viec, qua cac ASIC rack-mount co kich thuoc day du, den cac don vi lam mat bang nuoc can ha tang lam mat chuyen dung. Tho dao gia dinh se khong tao ra doanh thu dang ke nhung la cach thuc hanh de hoc cach dao hoat dong va dong gop hashrate cho mang. Tho dao cong nghiep la noi kinh te bat dau thuc su quan trong.
Phan mem va pool
Dao don vs. dao pool
Dao don co nghia la tu chay hoat dong dao cua ban mot cach doc lap. Ban nhan duoc toan bo phan thuong khoi neu tim thay mot khoi, nhung voi do kho mang hien tai, mot tho dao don le co the mat nhieu nam ma khong tim thay khoi nao. Doi voi hau het cac tho dao ngay nay, dao pool la lua chon thuc te.
Mining pool hoat dong nhu the nao
Mot mining pool ket hop hashrate cua nhieu tho dao. Khi bat ky thanh vien nao cua pool tim thay mot khoi hop le, phan thuong duoc chia cho tat ca nhung nguoi tham gia dua tren cong viec tinh toan ma ho da dong gop. Dieu nay mang lai cac khoan thanh toan nho hon, thuong xuyen hon thay vi nhung khoan lon, hiem hoi.
Cac pool chi dinh "shares" — phien ban de hon cua cau do thuc — de xac minh rang moi tho dao thuc su dang lam viec. Phan thuong cua ban ty le voi so shares ban gui.
Phuong thuc thanh toan
- FPPS (Full Pay Per Share): tra mot so tien co dinh cho moi share gui, bao gom uoc tinh phi giao dich. Cung cap thu nhap du doan nhat.
- PPLNS (Pay Per Last N Shares): tra dua tren shares gui trong mot khoang thoi gian xung quanh khi mot khoi duoc tim thay. Phan thuong bien dong nhieu hon nhung co the cao hon theo thoi gian.
- PPS+ (Pay Per Share Plus): mot dang ket hop tra muc co dinh cho phan tro cap khoi cong them phan phi giao dich thuc te.
Cac mining pool lon
Cac mining pool Bitcoin lon nhat theo ty le hashrate bao gom Foundry USA, AntPool, F2Pool, ViaBTC va Binance Pool. Khi chon pool, hay xem xet cau truc phi, phuong thuc thanh toan, nguong thanh toan toi thieu, vi tri may chu va danh tieng. Khong nen coi bat ky pool don le nao la mot khuyen nghi — su da dang giua cac pool la tot hon cho mang Bitcoin.
Phan mem dao
Phan mem dao ket noi phan cung cua ban voi mang Bitcoin (hoac pool cua ban). Cac lua chon pho bien bao gom CGMiner, BFGMiner va cac firmware do nha san xuat cung cap. Hau het cac tho dao ASIC hien dai di kem voi phan mem tich hop ma ban cau hinh qua giao dien web — ban nhap URL pool, ten worker va mat khau, va may se xu ly phan con lai.
Kinh te dao
Phan thuong khoi
Khi mot tho dao thanh cong them mot khoi vao blockchain, ho nhan duoc phan thuong gom hai phan: tro cap khoi (bitcoin moi tao) va phi giao dich tu tat ca cac giao dich trong khoi do.
Tro cap khoi bat dau o muc 50 BTC vao nam 2009 va duoc giam mot nua khoang bon nam mot lan (moi 210.000 khoi) trong su kien goi la "halving". Lan halving gan nhat xay ra vao thang 4 nam 2024, giam tro cap tu 6,25 BTC xuong 3,125 BTC moi khoi. Lan halving tiep theo duoc du kien vao khoang nam 2028.
Lich trinh halving nay co nghia la tong cung cua Bitcoin duoc gioi han o 21 trieu dong, voi phan cuoi cung cua mot bitcoin du kien se duoc dao vao khoang nam 2140.
Phi giao dich
Khi tro cap khoi giam theo thoi gian, phi giao dich tro thanh phan ngay cang quan trong trong doanh thu cua tho dao. Phi do nguoi dung tra khi muon giao dich cua ho duoc xac nhan va bien dong theo nhu cau mang. Trong nhung giai doan hoat dong cao, phi co the rat dang ke.
Can nhac ve diem hoa von
Loi nhuan dao phu thuoc vao nhieu yeu to:
- Chi phi dien: chi phi van hanh lon nhat. Cac tho dao tim nhung dia diem co dien re va on dinh.
- Chi phi va hieu qua phan cung: may hieu qua hon (J/TH thap hon) kiem duoc nhieu hon so voi muc tieu thu dien.
- Do kho mang: khi nhieu hashrate tham gia mang, phan thuong cua moi tho dao giam.
- Gia Bitcoin: phan thuong tinh bang BTC, nen doanh thu tinh bang tien phap dinh bien dong theo thi truong.
- Lam mat va ha tang: dao tao ra nhiet dang ke, va duy tri nhiet do van hanh toi uu lam tang chi phi.
Hau het cac tho dao ca nhan se thay kho khan de canh tranh voi cac hoat dong quy mo lon huong loi tu kinh te quy mo, gia dien si va co so toi uu. Truoc khi dau tu vao phan cung dao, hay tinh toan can than chi phi va doanh thu du kien bang may tinh loi nhuan dao.
Dao hosting va cloud
Dao hosting
Dao hosting (con goi la colocation) co nghia la ban so huu phan cung dao, nhung no duoc dat va van hanh tai mot co so dao chuyen dung. Co so cung cap dien, lam mat, ket noi internet va bao tri vat ly. Ban tra phi hosting (thuong tinh theo kilowatt-gio) va giu lai phan thuong dao. Day co the la cach hop phap de dao ma khong phai tu quan ly ha tang.
Cloud mining
Cac dich vu cloud mining tuyen bo cho phep ban thue hashrate ma khong can so huu phan cung nao. Ban tra truoc hoac theo hinh thuc dang ky va nhan phan thuong dao ty le voi hashrate da mua.
Hay het suc can than voi cloud mining. Linh vuc cloud mining bi tran ngap boi lua dao va mo hinh kinh doanh khong ben vung. Nhieu cong ty cloud mining hoa ra la cac mo hinh Ponzi sup do khi khoan thanh toan cua khach hang moi khong the trang trai duoc loi nhuan da hua.
Dau hieu canh bao
- Loi nhuan dam bao hoac thanh toan co dinh hang ngay — thu nhap dao hop phap bien dong
- Khong co bang chung co the xac minh ve hoat dong dao hoac vi tri co so
- Tien thuong gioi thieu chiem phan lon mo hinh kinh doanh
- Hop dong nhanh chong tro nen khong co lai va khong the huy
- Doi ngu an danh hoac dang ky cong ty khong the xac minh
- Loi nhuan cao khong thuc te so voi viec tu chay phan cung o do kho hien tai
Neu ai do dang cung cap cho ban loi nhuan dam bao tu dao ma khong can no luc nao tu phia ban, thi gan nhu chac chan la lua dao. Dao hop phap la mot nganh kinh doanh canh tranh, von lon voi loi nhuan bien dong.
Proof of Work
Proof of work (PoW) la co che dong thuan bao mat mang Bitcoin. No yeu cau cac tho dao bo ra no luc tinh toan thuc su — va do do nang luong thuc su — de tao ra cac khoi hop le. Day la dieu lam cho blockchain cua Bitcoin khang chong duoc voi su gia mao.
Khai niem nay don gian: tao ra mot proof of work hop le la co y kho khan va ton tai nguyen, nhung xac minh rang bang chung cua nguoi khac la hop le thi nhanh va de dang. Bat ky nut nao tren mang deu co the kiem tra ngay lap tuc lieu bam cua mot khoi co dat muc tieu do kho hay khong.
Tai sao tieu thu nang luong quan trong
Viec su dung nang luong cua Bitcoin doi khi bi chi trich, nhung no phuc vu mot muc dich bao mat co ban. Chi phi dao (chu yeu la dien) la dieu lam cho viec tan cong mang tro nen dat den muc cam. De viet lai du chi mot khoi lich su giao dich, ke tan cong se phai lam lai tat ca proof of work cho khoi do va moi khoi tiep theo — nhanh hon phan con lai cua mang dang them cac khoi moi. Voi hashrate toan cau hien tai, dieu nay se doi hoi mot khoan chi tieu lon va lien tuc ve nang luong va phan cung vuot xa bat ky loi ich tiem nang nao tu gian lan.
Noi cach khac, proof of work chuyen doi dien thanh bao mat. Mang tieu thu cang nhieu nang luong, viec tan cong cang dat. Day la su danh doi bao mat co ban cua Bitcoin.
Do kho dao
Do kho dieu chinh nhu the nao
Giao thuc Bitcoin bao gom mot dieu chinh do kho tu dong xay ra moi 2.016 khoi (khoang hai tuan mot lan). Mang do thoi gian can de dao 2.016 khoi truoc do va dieu chinh muc tieu do kho sao cho 2.016 khoi tiep theo se mat khoang 14 ngay voi tong hashrate hien tai.
- Neu cac khoi duoc tim thay nhanh hon mot khoi moi 10 phut, do kho tang.
- Neu cac khoi duoc tim thay cham hon mot khoi moi 10 phut, do kho giam.
Co che tu dieu chinh nay la dieu giu cho viec san xuat khoi cua Bitcoin on dinh o khoang mot khoi moi 10 phut, bat ke co bao nhieu suc manh dao tren mang.
Do kho va hashrate
Do kho lien quan truc tiep den tong hashrate tren mang. Khi cac tho dao moi tham gia va tong hashrate tang, cac khoi duoc tim thay qua nhanh, nen do kho tang. Khi cac tho dao tat may (vi du, neu gia Bitcoin giam duoi chi phi hoa von), hashrate giam va do kho cuoi cung giam.
Trong lich su Bitcoin, do kho da theo xu huong tang manh khi phan cung dao cai thien va su chap nhan tang. Dieu nay co nghia la cung mot phan cung kiem duoc it bitcoin hon theo thoi gian khi canh tranh tang.
Dieu nay co nghia gi cho tho dao
Do kho tang lam giam doanh thu du kien cua moi tho dao. Neu do kho tang gap doi, mot tho dao voi cung phan cung se kiem duoc khoang mot nua so bitcoin moi ngay. Day la ly do tai sao hieu qua quan trong: cac tho dao co chi phi dien thap nhat va phan cung hieu qua nhat se ton tai qua nhung lan tang do kho day cac nha van hanh kem hieu qua hon ra khoi thi truong.
Bat dau
Neu ban da san sang bat dau dao Bitcoin, day la tong quan thuc te ve cac buoc can thuc hien:
- Co mot vi Bitcoin Ban can mot vi de nhan thanh toan dao. Doi voi dao, mot dia chi nhan don gian la du — pool cua ban se gui phan thuong den do. Xem huong dan bat dau va khuyen nghi vi cua chung toi.
- Chon phuong phap dao cua ban Quyet dinh xem ban muon mua va van hanh phan cung ASIC cua rieng minh, su dung dich vu dao hosting, hay (voi su than trong thich hop) xem xet cloud mining. Chay phan cung cua rieng ban cho ban nhieu quyen kiem soat nhat.
- Chon mot mining pool Tham gia mining pool de nhan thanh toan deu dan. So sanh cac pool dua tren phi, phuong thuc thanh toan, nguong toi thieu va danh tieng. Hau het cac pool co quy trinh dang ky don gian.
- Thiet lap phan cung va phan mem Ket noi phan cung dao voi nguon dien va internet. Truy cap giao dien web de cau hinh URL pool, ten worker va dia chi thanh toan. Dam bao lam mat va thong gio day du.
- Giam sat va bao tri Theo doi hashrate, nhiet do phan cung va bang dieu khien pool cua ban. Dao la mot hoat dong lien tuc — phan cung can giam sat, cap nhat firmware va bao tri dinh ky.
Mot luu y thuc te: Hau het cac tho dao ca nhan ngay nay khong dao co lai. Cac hoat dong quy mo lon voi quyen truy cap vao dien gia re va mua phan cung so luong lon thong tri nganh. Dao van co the dang gia de hoc hoi, ho tro mang, hoac nhu mot chien luoc tich luy dai han neu ban tin vao gia tri tuong lai cua Bitcoin — nhung dung mong doi loi nhuan de dang.