Proposals to strengthen the law against computer crime - put forward by Labour MP Tom Harris - have been included in a new bill going through Parliament.
Whole networks can crash with a Denial-of-service attack
Mr Harris sought to make all forms of interfering with a computer a crime and to increase sentences for hackers.
The Police and Justice Bill aims to clarify offences such as denial-of- service attacks which can debilitate computer networks.
It would also raise the penalty for hacking and using hacking "tools".
Mr Harris put forward a Private Member's Bill (PMB) to amend the 1990 Computer Misuse Act, saying the internet had changed beyond recognition since the current laws on hacking and spreading computer viruses were brought in.
A spokesman for the Home Office said the department "welcomed Mr Harris' commitment to this cause", adding that the tightening of computer crime law was an area it had been investigating.
The Police and Justice Bill, due to be debated for the first time next month, is expected include amendments to ensure all means of interference with a computer system are criminalised.
The bill would increase the penalty for unauthorised access to a computer from six months to five years.
The penalty for unauthorised modifying of a computer would increase from five to 10 years.
"While under the 1990 law it might be possible to get a prosecution for computer misuse, the new act would make it far easier," the spokesman said.
He said the number and sophistication of computer attacks, including denial-of-service had been growing and there was a need for "the sentences to reflect the crime".
Commenting on the proposed new laws, Glasgow South MP Mr Harris said: "This is excellent news. By including the measures of my Private Member's Bill in the Police and Justice Bill the government has sent out a powerful message that cyber-crime will not be tolerated.
"Updating the Computer Misuse Act (1990) is an important and crucial step in meeting the challenge posed by cyber-crime, which is costing this country billons of pounds a year."
He said the increase in penalties for certain offences would ensure "adequate provision" is made to criminalise all forms of denial-of-service attacks.
The Home Office spokesman said the Bill ratified a pan-European recommendation at the 2001 Council of Europe Cyber Crime Convention.