Remote Gear Support ...

Dan Long long at nic.near.net
Wed Sep 2 18:20:53 UTC 1992


Yes--we've run into the problem with the 4 and 8-way COS switches too.  Always
connect to an unused port before hanging up....

Dan

------- Forwarded Message

To: Jeff Wabik <jwabik at msc.edu>
cc: nearnet-ops
Subject: Re: Remote Gear Support .. 
In-reply-to: Your message of Wed, 02 Sep 92 12:28:01 -0500.
             <9209021728.AA02344 at sniper.msc.edu> 
Date: Wed, 02 Sep 92 14:15:19 -0400
From: "Dan Long" <long at bbn.com>

	From: Jeff Wabik <jwabik at msc.edu>
	Subject: Remote Gear Support .. 
	Date: Wed, 2 Sep 92 12:28:01 CDT
	
	I've been poking around (thru the Black Box catalog, for example) for
	equipment to help us support our remote network gear located near the
	NSS to which we attach.  I've had little success at finding the
	right pieces.  I'm wondering if any of you have implemented any of
	these (listed below) solutions, and if so, where you found the 
	equipment to do it; then subsequent sucess/failure information.

We've done all this stuff with (almost) stock Black Box gear.  I'll fax you a
copy of a diagram of a setup we actually implemented when we had a T1 line
going to Princeton and wanted to be able to power cycle the gear, access
various console ports, and switch a T1 line from one DSU/CSU to another.
It all worked fine.

	Not in any particular order, here are the functions I'd like to be able
	to perform remotely..  This is a "grandiose wish list", as it were.

		* Software switchable dial-up access to serial ports
		  on all gear (several ports):
	                                          To Device 1
	                                       +------------->
	                                       |+------------>
	                                       || To Device 2
	   Phone line    +-------+   +---------+++    .
	-----------------| Modem |---| Magic Box |    .
	                 +-------+   +-----------+    .
	                                       || To Device (n-1)
	                                       |+------------>
	                                       +------------->
	                                          To Device (n)


		  In this scenario, I dial into the modem to the "magic box",
		  and give it some character code or sequence to attach me to
		  the specified port.  I can escape back to the magic-box 
		  and request subsequent connections without having to 
		  redial.  [Black box has one of these for 4 ports, but I hear
		  its not too good.  Any experiences?]

We do this with their 4-way or 8-way switch.  There's also a (nicer) box from
Newbridge called the 1008 Mainstreet Data Controller ($1100) (703-834-3600).

		* Power Cycle any of "n" pieces of remote hardware via RS232
		  interface and ASCII selection.   Ideally, this box attaches
		  to one of the ports of the serial switch above, and asks me
		  which piece of the "n" attached pieces of hardware should be
		  cycled.  [Black box has one of these for a single piece of
		  equipment.  It requires a dedicated phone line, and uses
		  telco tones to trigger a cycle.]

We use the black box LOR-II and we just change a wire on the relay to make it
be Normally-Closed instead of Normally-Open.  Works great.  Power goes off as
long as you stay connected to the appropriate serial port on the switch.
Be aware of the LOR's load limitations, however.  Another option (which I
haven't tested is:

    Heathkit/Radio Shack sell the BSR wireless controlers which has an
    RS-232C interface.  These devices communicate over the AC power
    lines and can operate relays wich can switch an inductive load of
    up to 20 Amps - which is sufficent for the devices we would use.
    The problem with this technology is that if the power lines have
    a lot of noise, the units may not respond to commands.
    The benifit is they are small, cheap, and work well.

		* T1 line switch:

	             
	 Incoming T1     +--------+                 +-----------+
	                 |        |-----------------| CSU/DSU 1 |----> To router 1
	-----------------| Switch |                 +-----------+
	                 |        |-----------------| CSU/DSU 2 |----> To router 2
	                 +--------+                 +-----------+
			     ^
			     |
			     V 
			 RS232 Input

		  Ideally, this box also attaches to one of the ports on the 
		  n-by serial switch above, and has some sort of menu or 
		  ASCII code line selection mechanism.  Being a software guy,
		  I thought about wiring this up using a switch for RS232 from
		  Black Box..  Hardware people informed me that this wasn't
		  a good idea.  

This may not be a good idea (may even be illegal) but we needed to do it and it
worked like a champ (saved our asses at least once).  We used a Black Box
tone-activated-talking switch and wired the 4-wire T1 line up to it.  It
operates based on touch-tone input (not RS232).  Since we only wanted one phone
line, then we put the equivalent of an ASD-4 (they used to have a 2-port
version called a Call Distribution Switch) in front to select either the TATS
or the modem/8-way box.  And we put security codes on the TATS and modem (a
security modem from black box) so random people couldn't toy with our gear.

	Again, these are the thoughts on my mind... and an "ideal wish list". 
	I'd appreciate hearing about any implementations or similar tools
	that you have experience with.

Works for us.  Your mileage may vary.  Good luck.

Regards,
Dan

------- End of Forwarded Message






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