Toshiba B-FV4 Series Manual page 291

9. NETWORK
EO18-33030
9.1 Network Architecture
The data link is on the data link layer. Its task is to create and manage a reliable data transmission
between two adjacent nodes in a network via MAC addresses. It divides the data from the network
layer into bits, encodes these bits into frames prior to transmission, and decodes them at the
destination. The data link also provides the error control and flow control. The error control uses a
frame check sequence (FCS) to ensure that the delivered frames are intact, and the flow control
ensures that the fast sender doesn't overwhelm the slow receiver with data.
This architecture allows up to five computers to connect to a printer via the same port. When you
turn on your printer, it opens the maximum number of ports, and is waiting for a session request.
Once your printer receives a request, it establishes a session and set it as "connected." If all of the
sessions are occupied, no more connection is allowed. In this case, your printer returns the RST
signal to the computer that made a request via the TCP protocol. When your printer finishes its
communication with the computer, it releases the session to get ready for a new connection.
Data processing is determined by the connection priority. When your printer connects to multiple
computers, it only processes the data from the oldest session (the first connected computer),
except for the WB, WR or WS commands. These three TPCL commands will be processed no
matter which computer sends them. The connection priority changes when there is a disconnection.
Other computer needs to wait until its session becomes the oldest.
9-2