1.   Both companies make equipment that helps link computers together.

2.   All three companies build equipment to link computers.

3.   Both ID systems rely on a unique number contained on a piece of computer hardware called an Ethernet card, which is used to link computers in corporate networks.

4.   Companies that make equipment to link computers into networks also gained.

5.   Compaq also has acquired several companies that make systems to link computers in networks, so it can sell entire computer systems and not just desktop PCs.

6.   Customers, such as banks, use the equipment to link computers at branch offices to their machines at their main offices.

7.   For example, the devices can help link computers at hospitals together through a high-speed network so they can exchange patient records.

8.   Nextream develops software to link mainframe computers to the Internet and sells it mainly to Korean banks and other financial institutions.

9.   Other big gainers for the week were Burlington-based Shiva Corp., a maker of equipment to link computers in field offices to those in the home office.

10.   Software makers are boosting profits as corporations link computers through networks and snap up programs to manage their computer systems, inventory and manufacturing.