From: rtcoffin@austin.ibm.com (Coffin)
Subject: Item #398: OBP-TFTP: additional 'ping' parameters
Date: Thu, 12 Dec 96 11:51:11 -0600



P1275 Openboot Working Group Proposal -- Proposal #:398 Ver <1.0>

Title:          Additional "ping" Command Parameters

Author:         R. T. Coffin

Date:           12/12/96

Ed/Tech:        Technical

Synopsis:       Need to add IP address for sending (client IP) machine

Doc & Version:  TFTP Booting Extension, Recommended Practice, Version 0.7

Problem:        The present definition of the Ping Command, 'ping ip,gip,
                timeout' needs to be enhanced to include both the 'client'
                and 'server' IP addresses, where 'client-ip' is the machine
                issuing the "ping" command and 'server-ip'(ip) is the
                target machine.

Proposal:

The "ping" User Interface Command needs the following additional arguments as
defined in Section 6.0, ping User Interface command, of Open Firmware
Recommended Practice: TFTP Booting Extension, Version 0.7:

     ping   device-indentifier:[device arguments,]server-ip,
            client-ip,[gateway-ip][,timeout]

     where:

        device-identifier:      device path of network device.

        device arguments:       [promiscuous,][speed=n,][duplex=mode]

        server-ip:              target machine assigned IP address being
                                "pinged" in dotted decimal notation.

        client-ip:              the machine issuing the "ping" Command assigned
                                IP address in dotted decimal notation.

        gateway-ip:             if server is on another network, this is the
                                first "hop" in the route to the server, via a
                                gateway assigned IP address in dotted decimal
                                notation.

        timeout:                if the machine being "pinged" does not respond,
                                timeout "ping" Command (time in
                                n milliseconds(ms)).  Default value is 10ms if
                                not specified.

---------------------- END OF PROPOSAL ----------------------------------------

                      ADDITIONAL INFORMATION

------------ Attached Text - IBM Implementation Algorithm ---------------------

An IBM Implementation Algorithm for the current "ping" algorithm is being
done as follows:

    1. ARP the "client-ip" address to see if it is  being used
       by another machine.

    2. If a gateway argument is specified, ARP this address
       to get its hardware address.  If a valid ARP reply is
       received, then this address will be used as the physical
       layer destination address.

    3. If the gateway IP argument is zero then we assume that
       the server IP address is on the local network.  In this
       case the server IP will be ARPed.  If a valid ARP reply
       is received, then this address will be used as the physical
       layer destination address.

    4. Send an ICMP echo request to the destination address (determined in
       step 2 and 2a).
       Note:
            The physical layer destination address is determined by step 2.
            The IP header destination address contains the "server-ip"
            address.

    5. If no reply is received within the timeout period, then the ping 
function
       will return "fail".



-- 
 Regards,                 ______________________________________
                          \ R. T. Coffin, IBM - Austin, TX.     \
     /_)   /')  /_)        \ RS/6000 Hardware Architecture       \
    /__)  /_/  /__)         \ (512) 838-8240  Fax: (512) 838-6783 \
                             \  e-mail: rtcoffin@austin.ibm.com    \
================== N4LXK -30- ======================================\



[ P1275 Item #398 -- Received: Thu Dec 12 09:50:47 PST 1996 ]