ec man page on Ultrix

Printed from http://www.polarhome.com/service/man/?qf=ec&af=0&tf=2&of=Ultrix

ec(4)				  Unsupported				 ec(4)

Name
       ec - 3Com 10 Mb/s Ethernet interface

Syntax
       device ec0 at uba0 csr 0161000 vector ecrint eccollide ecxint

Description
       The  interface  provides access to a 10 Mb/s Ethernet network through a
       3com controller.

       The hardware has 32 kilobytes of	 dual-ported  memory  on  the  UNIBUS.
       This memory is used for internal buffering by the board, and the inter‐
       face code reads the buffer contents directly through the UNIBUS.

       The host's Internet address is specified at boot time with  an  SIOCSI‐
       FADDR  ioctl.   The  interface  employs the address resolution protocol
       described in to dynamically map between Internet and Ethernet addresses
       on the local network.

       The interface software implements an exponential backoff algorithm when
       notified of a collision on the cable. This algorithm utilizes a	16-bit
       mask  and the VAX-11's interval timer in calculating a series of random
       backoff values. The algorithm is as follows:

       1.   Initialize the mask to be all 1's.

       2.   If the mask is zero, 16 retries have been made and we give up.

       3.   Shift the mask left one bit and formulate a backoff by masking the
	    interval  timer  with the mask (this is actually the two's comple‐
	    ment of the value).

       4.   Use the value calculated in step 3 to delay before	retransmitting
	    the packet.	 The delay is done in a software busy loop.

       The interface normally tries to use a ``trailer'' encapsulation to min‐
       imize copying data on input and output.	This may  be  disabled,	 on  a
       per-interface  basis,  by setting the IFF_NOTRAILERS flag with an SIOC‐
       SIFFLAGS ioctl.

Diagnostics
       ec%d: send error.
       After  16  retransmissions  using  the  exponential  backoff  algorithm
       described above, the packet was dropped.

       ec%d: input error (offset=%d).
       The hardware indicated an error in reading a packet off the cable or an
       illegally sized packet.	The buffer offset value is printed for	debug‐
       ging purposes.

       ec%d: can't handle af%d.
       The  interface  was  handed  a  message	with addresses formatted in an
       unsuitable address family; the packet was dropped.

See Also
       intro(4n), inet(4f), arp(4p)

				      VAX				 ec(4)
[top]

List of man pages available for Ultrix

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net