2.11BSD#431 - /usr/man/cat4/ns.0

NS(4F)		    UNIX Programmer's Manual		   NS(4F)


NAME
     ns - Xerox Network Systems(tm) protocol family

SYNOPSIS
     Not currently supported under 2.11BSD

DESCRIPTION
     The NS protocol family is a collection of protocols layered
     atop the Internet Datagram Protocol (IDP) transport layer,
     and using the Xerox NS address formats.  The NS family pro-
     vides protocol support for the SOCK_STREAM, SOCK_DGRAM,
     SOCK_SEQPACKET, and SOCK_RAW socket types; the SOCK_RAW
     interface is a debugging tool, allowing you to trace all
     packets entering, (or with toggling kernel variable, addi-
     tionally leaving) the local host.

ADDRESSING
     NS addresses are 12 byte quantities, consisting of a 4 byte
     Network number, a 6 byte Host number and a 2 byte port
     number, all stored in network standard format.  (on the VAX
     these are word and byte reversed; on the Sun they are not
     reversed).  The include file <netns/ns.h> defines the NS
     address as a structure containing unions (for quicker com-
     parisons).

     Sockets in the Internet protocol family use the following
     addressing structure:

     struct sockaddr_ns {
	  short          sns_family;
	  struct ns_addr sns_addr;
	  char	    sns_zero[2];
     };

     where an ns_addr is composed as follows:

     union ns_host {
	  u_char	 c_host[6];
	  u_short	 s_host[3];
     };

     union ns_net {
	  u_char	 c_net[4];
	  u_short	 s_net[2];
     };

     struct ns_addr {
	  union ns_net	 x_net;
	  union ns_host  x_host;
	  u_short   x_port;
     };


Printed 11/26/99	January 27, 1996			1


NS(4F)		    UNIX Programmer's Manual		   NS(4F)


     Sockets may be created with an address of all zeroes to
     effect ``wildcard'' matching on incoming messages.  The
     local port address specified in a bind(2) call is restricted
     to be greater than NSPORT_RESERVED (=3000, in <netns/ns.h>)
     unless the creating process is running as the super-user,
     providing a space of protected port numbers.

PROTOCOLS
     The NS protocol family supported by the operating system is
     comprised of the Internet Datagram Protocol (IDP) idp(4P),
     Error Protocol (available through IDP), and Sequenced Packet
     Protocol (SPP) spp(4P).

     SPP is used to support the SOCK_STREAM and SOCK_SEQPACKET
     abstraction, while IDP is used to support the SOCK_DGRAM
     abstraction.  The Error protocol is responded to by the ker-
     nel to handle and report errors in protocol processing; it
     is, however, only accessible to user programs through heroic
     actions.

SEE ALSO
     intro(3), byteorder(3N), gethostbyname(3N), getnetent(3N),
     getprotoent(3N), getservent(3N), ns(3N), intro(4N), spp(4P),
     idp(4P), nsip(4)
     Internet Transport Protocols, Xerox Corporation document
     XSIS-028112
     An Advanced 4.3BSD Interprocess Communication Tutorial


Printed 11/26/99	January 27, 1996			2