Conference netcad::hub_mgnt

957.0. "Multi 900 configs with DB900MX and routing" by TROFS::WEBSTER (Netwerks-R-us) Wed May 04 1994 14:41

I have to respond ASAP to a tender for hub products. I have put together the 
following configuration, but I need to know if is valid, or what other products
could best be used to solve the problem.

The RFP shows the following configuration that needs to be created.


  +---------+			+---------+		+---------+
  |  HUB C  |<-----fibre------->|  HUB B  |<---fibre--->|  HUB D  | Student
  +---------+			+---------+		+---------+   LANs
				     ^
				     |
				   fibre
				     |
				     v 
				+---------+
				| ROUTER  |----> WAN
				+---------+
				     ^
				     |
				     v
				+---------+
				|  HUB A  | 			Adminstration
				+---------+

Requirements are;
	1. Rack/Stack 10bT hubs with SNMP management
	2. bridged or switched ethernet between hubs B, C, and D (IP & IPX)
	3. routed ethernet between HUBs B/C/D and A and WAN (IP & IPX)
	4. router to have T1 capabilities

I came up with the following solution, based on the DB900MX having routing
capabilities;

  HUB C				  HUB B			  HUB D
+---+---+			+---+---+		+---+---+
| D | D |			| D | D |		| D | D |
| R | R |			| R | R |		| R | R |
| 9 | 9 |			| 9 | 9 |		| 9 | 9 |
| 0 | 0 |			| 0 | 0 |		| 0 | 0 |
| 0 | F |			| 0 | F |		| 0 | F |
| T | S |			| T | S |		| T | S |
| M |   |			| M |   |		| M |   |
+---+---+			+---+---+		+---+---+
      ^				      ^			      ^
      |				      |			      |
      |				      +--------+	      |
      +--------------------------------------+ |	      |
	   HUB A			     | |	      |
	+---+---+---+---------+---+	     | |	      |
	| D | D | D |         | D |	     | |	      |
	| R | B | B |<-seg 2->| R |<--fibre--+ |	      |
	| 9 | R | 9 |<-seg 3->| 9 |<--fibre----+	      |
	| 0 | O | 0 |<-seg 4->| 0 |<--fibre-------------------+
	| 0 | U | 0 |<----+   | 0 |
	| T | T | M |     |   | F |
	| M | R | X |     |   | P |
	+---+---+---+-----|---+---+
	  ^   ^   ^       |
	  |   |   |<seg 1 |
	  |   +---+       |
	  +---seg 5-------+

In this configuration, the DB900MX would perform routing between all segments
(seg 1 being the backplane coax segment and seg 2 thru 5 are IMBs) and the 
DBrouter 90 would provide the WAN connection.

Is this config valid or is there a more cost effective way to solve this 
problem? Customer is a high school, so there is not alot of funding.

Competetion will be usual, but there will also be some lower cost hubs
quoted by some responders. Can any other hub vendor provide this solution as
cost effectively as Digital? I see Digital as being the only vendor that can
supply the complete solution, in hub products with manangement, at the lowest 
price. The only weaknesses I can see is 1) that we do not have an access 
router product with multiple ethernet ports that is hub based (other than 
the NIS) and 2) the Brouter is not completly managable from HUBwatch.

We now need such a product like a DB900MX with a WAN port to allow multiple 
segments into hub. Not sure if there is much of a demand for such a product,
but schools are typical where they must protect the traffic between admin 
people and students (who may be access the Internet, connecting to other 
schools, etc...) but can only afford one WAN connection to school.

-Larry Webster
 Network Planning Consultant
 DTN 624-4249

Rev 2.0 of the DB900MX will provide routing.

See the usual place for schedule and other info.

Tom Hood
HUBwatch