NAME

       tcpclo - DTN TCPCL-compliant convergence layer adapter output task

SYNOPSIS

       tcpclo remote_hostname[:remote_port_nbr]

DESCRIPTION

       tcpclo is a background "daemon" task that connects to a remote node's TCP socket at
       remote_hostname and remote_port_nbr.  It sends a contact header, and it records the
       acknowledgement flag, reactive fragmentation flag and negative acknowledgements flag in
       the contact header it receives from its peer tcpcli task.  It then begins extracting
       bundles from the queues of bundles ready for transmission via TCP to this remote bundle
       protocol agent and transmitting those bundles over the connected socket to that node.
       Each transmitted bundle is preceded by message type, segmentation flags, and an SDNV
       indicating the size of the bundle (in bytes).

       If not specified, remote_port_nbr defaults to 4556.

       Note that tcpclo is not a "promiscuous" convergence layer daemon: it can transmit bundles
       only to the node to which it is connected, so scheme configuration directives that cite
       this outduct need only provide the protocol name and the outduct name as specified on the
       command line when tcpclo is started.

       tcpclo is spawned automatically by bpadmin in response to the 's' (START) command that
       starts operation of the Bundle Protocol, and it is terminated by bpadmin in response to an
       'x' (STOP) command.  tcpclo can also be spawned and terminated in response to START and
       STOP commands that pertain specifically to the TCP convergence layer protocol.

EXIT STATUS

       "0" tcpclo terminated normally, for reasons noted in the ion.log file.  If this
           termination was not commanded, investigate and solve the problem identified in the log
           file and use bpadmin to restart the TCPCL protocol.

       "1" tcpclo terminated abnormally, for reasons noted in the ion.log file.  Investigate and
           solve the problem identified in the log file, then use bpadmin to restart the TCPCL
           protocol.

FILES

       No configuration files are needed.

ENVIRONMENT

       No environment variables apply.

DIAGNOSTICS

       The following diagnostics may be issued to the ion.log log file:

       tcpclo can't attach to BP.
           bpadmin has not yet initialized Bundle Protocol operations.

       No such tcp duct.
           No TCP outduct with duct name matching remote_hostname and remote_port_nbr has been
           added to the BP database.  Use bpadmin to stop the TCP convergence-layer protocol, add
           the outduct, and then restart the TCP protocol.

       CLO task is already started for this duct.
           Redundant initiation of tcpclo.

       Can't get IP address for host
           Operating system error.  Check errtext, correct problem, and restart TCP.

BUGS

       Report bugs to <ion-bugs@korgano.eecs.ohiou.edu>

SEE ALSO

       bpadmin(1), bprc(5), tcpcli(1)