Re: agenda items for SF ? ISPs document

[Roy Brabson <rbrabson@us.ibm.com>]

> One point I would like to raise about IPv6 in the datacenter
> is load balancers. They basically are NAT boxes dispatching the traffic
> to a number of servers. Are we going to need NATv6 afterall?

I guess that depends on the load balancing device.  I'm familiar with many 
which do not use NAT for dispatching traffic.  Instead, the load 
balancer(s) advertise a server address to which client traffic is 
directed.  Each server which is part of the load balancing group also 
defines the same address, but in a manner such that the address is not 
advertised if the server is running dynamic routing protocol.  Depending 
on the proximity of the load balancer to the servers, the load balancer 
may rewrite the destination MAC address to direct the packet to the chosen 
server or may use some form of tunneling (such as GRE) to send the packet 
to the chosen server.  Neither approach requires the use of NAT.

> Anyway, I think this concern is specific to the big datacenter
> and should be addressed in the ISP scenario.

I don't agree, at least not for the enterprise customers I work with. Many 
use and deploy load balancers within the datacenter and do not rely on the 
ISP to provide this type of service.  I would see this as belonging within 
the Enterprise scenario document instead of the ISP scenario document.

Roy