The company has posted a version of Explorer 3.0 browser with 128-bit Secure Sockets Layer (SSL) encryption to its Web site. The move matches a similar initiative from rival Netscape Communications, which announced a 128-bit encrypted version of its Navigator browser last month.
The standard versions of both Explorer 3.0 and Navigator include 40-bit encryption software, which security experts say is much easier for hackers to crack.
Both Microsoft and Netscape got permission to release the stronger encryption from the State Department by promising to check the country of origin and Internet address of everyone requesting to download the software, and asking users to sign an affidavit affirming their U.S. citizenship.
The two companies are trying to work around the government edict that forbids export of 128-bit encryption software, which it classifies as a "munition." The federal government, claiming terrorists and other criminals could use the more powerful encryption, restricts the export of encryption software to 40-bit programs.
Vendors oppose that limit, contending that they need higher forms of encryption to secure business communications and to build global applications. The efforts by Microsoft and Netscape to get approval for tougher encryption software could help lift the export restrictions, analysts said.