[strongSwan] Ballpark number of users and Load balancing

[kgardenia42]

Hi,

I am using strongswan for mobile clients.

Can anyone give me a rough idea of how many clients I can expect (say)
an Amazon EC2 large instance to handle.  I searched for benchmarks but
found varying/contrasting results.  I found the integrated load test
tool docs and intend to run this tomorrow but I am not sure to what
extent it emulates *real* users.

Does anyone have a ballpark figure for real life users?  I realize it
depends on usage but I just am looking for a rough "I won't quote you"
ballpark.  Should I roughly expect hundreds?  Or thousands?  Or tens
of thousands even?

Secondly, I am investigating load balancing possibilities. Ideally I
would like a pool of (say) 4 strong-swans all of which can share a
load.  I'm not sure if sharing load would mean user stickiness or some
shared state across nodes but source ip stickiness would be acceptable
I guess.

I read this post:
    http://www.mail-archive.com/users@lists.strongswan.org/msg03427.html

As I see it the second option is not suitable for my use-case.  Right?
  The first option sounds rather involved. Will this even work in a
cloud (EC2) environment where the LAN IPs are not under my control
(unless perhaps VPC).  I'm happy to go down this road if it is the
"right thing to do".  Just wanted to see if there were any other
approaches to this.

Would a traditional load balancer with source address stickiness be a
viable solution?  Or is this a flawed approach?

Thanks!