A variable speed limit is one option being considered to improve traffic flow during peak periods on the M4.
New M4 signs are designed to provide journey information
The Highways Agency said it was looking at the option, among others including priority lanes, as part of a study into the east-west motorway.
A variable speed limit would be possible with the help of new M4 signs.
The agency said it hoped to produce a report into the various options early next year, although it added there was no timescale for a decision.
A spokesman for the Highways Agency said the options emerged following a series of exhibitions last year as part of the Thames Valley Journey Time Quality and Reliability Study.
He added: "People want improved traffic flows, especially with the London Olympics coming up.
"[A variable speed limit] is one of the options we are looking at, it's already used on the M25.
"We are not saying we are going to introduce this. It could be six or seven years down the line."
Other options include raised central barriers to reduce distractions, a continuous hard shoulder, junction improvements and better information during journeys.
Last month, the AA Motoring Trust said the 70mph speed limit on motorways should be raised to 80mph at certain times on parts of motorways, which have variable speed signs, to ease congestion.