The US National Security Agency is building a quantum computer to break the encryption that keeps messages secure, reports the Washington Post. The NSA project came to light in documents passed to the newspaper by whistle-blower Edward Snowden. The spying agency hopes to harness the special qualities of quantum computers to speed up its code-cracking efforts. The NSA is believed to have spent about $80m (£49m) on the project but it has yet to produce a working machine. If the NSA managed to develop a working quantum computer it would be put to work breaking encryption systems used online and by foreign governments to keep official messages secure, suggest the documents excerpted in the Post. The quantum computer is being developed under a research programme called Penetrating Hard Targets and is believed to be conducted out of a lab in Maryland. Many research groups around the world are pursuing the goal of creating a working quantum computer but those developed so far have not been able to run the algorithms required to break contemporary encryption systems. Current computers attempt to crack encryption via many different means but they are limited to generating possible keys to unscramble data one at a time. Using big computers can speed this up but the huge numbers used as keys to lock away data limits the usefulness of this approach. By contrast, quantum computers exploit properties of matter that, under certain conditions, mean the machine can carry out lots and lots of calculations simultaneously. This makes it practical to try all the possible keys protecting a particular message or stream of data. The hard part of creating a working quantum computer is keeping enough of its constituent computational elements, called qubits, stable so they can interact and be put to useful work. The NSA is not believed to have made significant breakthroughs in its work that would put it ahead of research efforts elsewhere in the US and Europe. However, the documents passed to the Post by Edward Snowden suggest the agency's researchers are having some success developing the basic building blocks for the machine. |
據(jù)《華盛頓郵報(bào)》報(bào)道,美國(guó)國(guó)家安全局正在研發(fā)一款用于破解加密信息的量子計(jì)算機(jī)。 愛(ài)德華?斯諾登向《華盛頓郵報(bào)》提供了相關(guān)的秘密文件,美國(guó)國(guó)家安全局的該項(xiàng)目由此曝光。 美國(guó)國(guó)家安全局希望利用這種特殊的量子計(jì)算機(jī)加快其密碼破解工作。 據(jù)信美國(guó)國(guó)家安全局已為該項(xiàng)目投資了約8000萬(wàn)美元(約合4900萬(wàn)英鎊),但仍未生產(chǎn)出一臺(tái)能夠工作的機(jī)器。 據(jù)《華盛頓郵報(bào)》引用的文件透露,如果美國(guó)國(guó)家安全局成功研發(fā)了量子計(jì)算機(jī),那么它將會(huì)被投入到破解網(wǎng)絡(luò)上和外國(guó)政府用來(lái)保障官方信息安全的加密系統(tǒng)。 美國(guó)量子計(jì)算機(jī)研發(fā)項(xiàng)目被稱(chēng)命名為“攻克難關(guān)”(Penetrating Hard Targets),據(jù)說(shuō)該項(xiàng)目正在馬里蘭州的一個(gè)實(shí)驗(yàn)室內(nèi)進(jìn)行。 世界上許多科研小組都志在研發(fā)一臺(tái)可工作的量子計(jì)算機(jī),但他們至今一直無(wú)法成功運(yùn)行破解現(xiàn)在加密系統(tǒng)所需要的算法。 目前的計(jì)算機(jī)嘗試通過(guò)許多不同的方法來(lái)破解加密,但它們產(chǎn)生的可能的密鑰只能在同一時(shí)間內(nèi)解密一個(gè)數(shù)據(jù)。使用大型計(jì)算機(jī)可以加速這個(gè)過(guò)程,但使用龐大的數(shù)字來(lái)作為密碼將數(shù)據(jù)加密使得這種方法的有效性大打折扣。 相比之下,量子計(jì)算機(jī)利用物質(zhì)的屬性,在一定條件下,這就意味著它可以同時(shí)進(jìn)行很多很多的計(jì)算。事實(shí)上,這就使得其可以嘗試所有破解保護(hù)某個(gè)特定消息或數(shù)據(jù)流的密碼。 研發(fā)可工作的量子計(jì)算機(jī)的難點(diǎn)在于,如何保持被稱(chēng)為“量子比特”的計(jì)算要素足夠穩(wěn)定,使他們能夠運(yùn)行并付諸有益的工作。 美國(guó)國(guó)家安全局對(duì)于量子計(jì)算機(jī)的研發(fā)被認(rèn)為并沒(méi)有取得顯著的突破,并沒(méi)有使其能夠領(lǐng)先于美國(guó)和歐洲其他地方的研究工作。然而,由愛(ài)德華?斯諾登透露給《華盛頓郵報(bào)》的文件卻表明,該機(jī)構(gòu)的研究人員在研發(fā)量子計(jì)算機(jī)基本的組裝模塊方面已取得了一些進(jìn)展。 (譯者 Chelseyxue 編輯 丹妮) |