already checked 

had already checked 

were already checking 

have already checked 

use to crash 

would crash 

crashes

was crashing 

have been implementing 

were implementing 

have implemented 

implemented 

was installing 

had installed 

installed

installs

is containing 

contained

has contained 

contains

is testing 

tests

has tested 

was testing 

To link different network segments and manage data flow within an organization 

To provide internet access to LANs 

To connect multiple cities 

To filter traffic within a single network segment 

Expands network coverage in a building 

Allows direct communication between computers within a LAN 

Shares files between computers 

Connects two similar or dissimilar networks and filters traffic 

Directly storing and processing data on the network 

Connecting similar or dissimilar types of networks 

Only allowing data traffic intended for other networks 

Filtering unwanted traffic from clogging the backbone 

Through the internet only 

Through coaxial cables only 

Through satellite and microwave relays 

Through direct wired connections