"So it may very well be there are circumstances where it is appropriate to have that discussion and potentially ask for information to be retained."
Asked if private networks at universities and companies could also be included, she said: "I don't think it would be right to exclude any particular type of network."
Mrs May added that the onus to show necessity and proportionality was on the Home Office when making individual decisions.
The Home Secretary also said the Government has attempted to "future proof" the legislation, although she admitted it would not "last forever and a day".
Mrs May voiced opposition to calls for a sunset clause to be attached which would give the laws an expiry date.
She told MPs and peers: "We've tried to balance here the need to in a sense future proof the legislation against the need not to produce something so wide-ranging that people feel it isn't clear on the powers that are going to be used."
She referred to the Regulation of Investigatory Powers Act 2000, which is currently the central piece of legislation covering the powers of spies and police to monitor the communications of terrorists and serious criminals.
Giving evidence to the draft investigatory powers bill joint committee, the Home Secretary said: "Ripa has been in place for 15 years. We would expect that this bill would stand the test of time."
Last week a security industry body suggested the new laws are unlikely to last for more than 10 years given the pace of technological change and called on ministers to revisit the legislation in five to seven years.
Asked about the possibility of revisiting the laws, Mrs May said: "I'm certainly not trying to give the impression that I think this is a bill that will last forever and a day.
"As technology advances it may be necessary to revisit the powers available and the legislative framework and the safeguards but I don't think advances in technology are going to move according to sunset clauses established by parliament."
She also stressed the bill would not make any changes in relation to encryption and insisted the government is not seeking "back door" access to communications.
Responding to questions about claims that bulk powers are "operationally counter-productive" because analysts are "blinded" by huge amounts of data, Mrs May said: "We do not collect all of the data all of the time."
She added: "You can't look for the needle in the haystack unless you've got the haystack. You do actually need to be able in some cases to to access this data."
Mrs May stressed that the powers would not be used for "mass surveillance".
Source: http://telegraph.feedsportal.com/c/32726/f/579309/s/4cd8a6f8/sc/13/l/0L0Stelegraph0O0Cnews0Cpolitics0Ctheresa0Emay0C120A98470A0CTheresa0EMay0Equestioned0Eby0Ecommittee0Eon0Esnoopers0Echarter0Bhtml/story01.htm