Technical data

BCSM IN A NUTSHELL 2008
© 2008 Brocade Communications Systems, Incorporated.
Page 37 of 44
BB CREDITS
Speed Credits/km Credits/50 km Credits/100 km
1 .5 25 50
2 1 50 100
4 2 100 200
Table 3: BB Credits
If you double the speed, or double the distance, you need to double the credits available on the port
If the speed doubles the maximum distance is cut if half
If you double the speed make sure you have the correct SFP for that speed
Starting with the 4 Gbit/sec ASICs, no port will be starved for BB credits. Any port can run in a buffer-limited
mode if need be. Also, no one port can take more than 255 credits.