kerberos capacity planning questions

[Tim Metz]

Greetings,

As part of a campus working group currently evaluating Kerberos product 
options, I have been tasked with researching the following two 
requirements for MIT Kerberos:

(1) Must house more than 200,000 accounts.
(2) Must issue more than 3 tickets per second.

Both would seem to be strictly a hardware/bandwidth constraint. 
I'd like to inquire however if anyone is aware of any software/product 
limitations relevant to housing 200,000 accounts?
For (2) I'll likely put together a small test environment to verify, any 
additional input on this is of course also welcome.

Thanks,

  - Tim