[nsp] GSR engine types?

[Rubens Kuhl Jr.]

|the crossbar from LC to LC. It has much less to do with IFG as it does
|with how efficiently the packet gets put into the fixed cell length in
|which the GSR supports. In some cases you get lots of overhead and,

I mentioned IFG because of line performance, not router performance... a
Gig-E link with 1.5 Mpps packets is the worst case processing scenario, but
it doesn't add up to 1 Gbps because of IFG. A bunch of jumbo frames cames
much closer to 1 Gbps, is the internal fabric worst case, but is easier to
handle from a processing point of view.




Rubens


-----Original Message-----
From: cisco-nsp-bounces at puck.nether.net
[mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Rubens Kuhl Jr.
Sent: Monday, January 12, 2004 5:12 PM
To: Tom (UnitedLayer)
Cc: cisco-nsp at puck.nether.net
Subject: Re: [nsp] GSR engine types?


Engine 2 cards like 3-port Gig-E are not wire-speed at all packet sizes.
A
flood of small packets can't amount to 3 Gbps because of IFG (Inter
Frame
Gap) limitations, but at near 1.5Mpps from each Gig-E interface, the 4
Mpps
engine runs out of steam.

The 4-port SFP card that comes with Engine 3 presents the same design
choice. This doesn't mean the 2 extra ports are useless; if some
external
factor can limit the possible aggregate traffic, it's fine. Redundant
(active-standby, not active-active) connections usually presents such a
scenario.


Rubens


----- Original Message ----- 
From: "Tom (UnitedLayer)" <tom at unitedlayer.com>
To: "Rubens Kuhl Jr." <rubens at email.com>
Cc: <cisco-nsp at puck.nether.net>
Sent: Monday, January 12, 2004 8:39 PM
Subject: Re: [nsp] GSR engine types?


> On Sun, 11 Jan 2004, Rubens Kuhl Jr. wrote:
> > Too bad (if this document is complete) that so called "edge
features"
still
> > aren't available on 3-port GigE cards (with Engine 3, it could
support 2
> > GigE at wire speed), requiring one to buy a 10-port GigE card.
>
> So the 3 port GigE cards can't even do 3Gbps total?

_______________________________________________
cisco-nsp mailing list  cisco-nsp at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/