glenda.party
term% ls -F
term% pwd
$home/manuals/9front/3/sdp
term% cat index.txt
SDP(3)                     Library Functions Manual                     SDP(3)



NAME
       sdp - secure datagram protocol

SYNOPSIS
       bind -a #Espec /net
       /net/sdp/clone
       /net/sdp/log
       /net/sdp/n
       /net/sdp/n/data
       /net/sdp/n/control
       /net/sdp/n/ctl
       /net/sdp/n/rstats
       /net/sdp/n/stats
       /net/sdp/n/status
       ...

DESCRIPTION
       The  sdp  device provides the interface to the Secure Datagram Protocol
       (SDP).  SDP (un)compresses and (de-)encrypts packets.  Spec is an inte‐
       ger from 0 to 15 identifying a stack.  Each stack is independent of all
       others: the only information transfer between them is via programs that
       mount multiple stacks.  Normally a system uses only one stack.  However
       multiple stacks can be used for debugging new networks or  implementing
       firewalls or proxy services.

       The  top  level directory contains a clone file, a log file, and subdi‐
       rectories numbered from zero to the number of  connections  opened  for
       this protocol.

       Opening  the clone file reserves a connection.  The file descriptor re‐
       turned from the open(2) will point to the control  file,  ctl,  of  the
       newly  allocated  connection.  Reading ctl returns a text string repre‐
       senting the number of the connection.  Connections may be  used  either
       to listen for incoming calls or to initiate calls to other machines.

       A  connection  is  controlled by writing text strings to the associated
       ctl file.  After a connection has been established  data  may  be  read
       from and written to data.  A connection can be actively established us‐
       ing the connect message (see also dial(2)).  A connection can be estab‐
       lished  passively  by  first using an announce message (see dial(2)) to
       bind to a local port and then opening the listen file (see dial(2))  to
       receive incoming calls.

       The following control messages are supported:

       accept file
              Accept  an  incoming  encrypted  connection on file, typically a
              data file.

       dial file
              Initiate a new encrypted connection on  file,  typically  a  UDP
              data file.

       drop permil
              Randomly  drop approximately one of every permil output packets,
              thus simulating network errors.

       cipher algorithm
              Use ciphering algorithm; choices are and

       auth algorithm
              Use authentication algorithm; choices are and

       comp algorithm
              Use compression algorithm; choices are and

       insecret secret
              Use secret to decrypt incoming packets.

       outsecret secret
              Use secret to encrypt outgoing packets.

SEE ALSO
       dial(2), ip(3)
       Robust Data Compression of  Network  Packets,  Sean  Dorward  and  Sean
       Quilan,    Bell    Labs,    Lucent   Technologies,   http://plan9.bell-
       labs.com/who/seanq/networkcomp.pdf.

SOURCE
       /sys/src/9/port/devsdp.c



                                                                        SDP(3)