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Conference netcad::hub_mgnt

Title:	DEChub/HUBwatch/PROBEwatch CONFERENCE
Notice:	Firmware -2, Doc -3, Power -4, HW kits -5, firm load -6&7
Moderator:	NETCAD::COLELLADT

Created:	Wed Nov 13 1991
Last Modified:	Fri Jun 06 1997
Last Successful Update:	Fri Jun 06 1997
Number of topics:	4455
Total number of notes:	16761

4265.0. "VNswitch questions" by CHR27::YEUNG (im2bz2p,ru?) Tue Mar 11 1997 12:24

My customer is planning to migrate their systems from running
on a shared thickwire Ethernet to a switched network utilizing
a VNswitch900EF module.  Here are some questions from them:

   1.	Suppose you have four nodes A, B, C, and D connected to
	a VNswitch900EF; and node A transmits to node B at the
	same time as node C transmits to node D; the packet from
	node A and the packet from node C arrives at the switch at
	the same time, is there an order in which the switch
	processes the packets?  Or are the packets switched
	simultaneously to their destinations?

   2.	Suppose nodes A, B, and C transmits simultaneously to node D;
	does the switch store the packets and send them one at a
	time to node D?

   3.	The customer currently has a network monitor application running
	on a VAX that passively collects traffic from the shared Ethernet
	and generates reports listing the time stamp, source, destination,
	protocol type, and size of all Ethernet packets.  The reports are
	used for troubleshooting timing problems in their realtime
	applications.  Are there any software products available that can
	provide the same functionality for a switched network? If not,
	does the VNswitch support a capability to duplicate all packet to
	a particular port so that the customer can connect their network
	monitor to that port?

Thanks

Tim

T.R	Title	User	Personal Name	Date	Lines
4265.1		NETCAD::GALLAGHER		`Tue Mar 11 1997 18:37`	25
	\| 2. Suppose nodes A, B, and C transmits simultaneously to node D; \| does the switch store the packets and send them one at a \| time to node D? Yes, the VNswitch is a store-and-forward switch. \| 3. The customer currently has a network monitor application running \| on a VAX that passively collects traffic from the shared Ethernet \| and generates reports listing the time stamp, source, destination, \| protocol type, and size of all Ethernet packets. The reports are \| used for troubleshooting timing problems in their realtime \| applications. Are there any software products available that can \| provide the same functionality for a switched network? If not, \| does the VNswitch support a capability to duplicate all packet to \| a particular port so that the customer can connect their network \| monitor to that port? An RMON Manager might suffice. We sell clearVISN RMON Manager. Refer to: http://npbwww.hpn.lkg.dec.com/dr/clearvsn/descrip/rmonmngr.txt As far as I know, the VN products don't support "mirror ports" which duplicate a ports traffic to another port for monitoring by a probe. -Shawn
4265.2	RMON Mirror coming	NETRIX::"[email protected]"	Ryan Price	`Wed Mar 12 1997 03:58`	20
	Hi, Firstly, IROCZ::COMMON_BROUTERS is the correct conference for VNswitches, since they use the Distributed Routing Software (or at least part of it). Next, the RMON Mirror will be available in a future release of the firmware, probably V2.0, which was due in April when we last heard at the SE Forum in January. Next, regarding .0, question 1. All the current VNswitch modules switch full- duplex on ALL ports at FULL line rate, so the short answer is: the packets are received/transmitted simultaneously from/to the relevant ports.(although you could get someone from engineering to tell you whether the switch processor is single or multi-threaded, I doubt that it's relevant). For an independent performance review, see http://www.tolly.com Ryan, NPBU, South Africa [Posted by WWW Notes gateway]