RE: ocean: do not boil

["Hesham Soliman (EAB)" <hesham.soliman@era.ericsson.se>]

Hi Margaret, 

Excellent start to the discussion, thanks.

  > I've been thinking about this question and trying to
  > come up with a good answer...
  > 
  > I'm actually thinking of this question a bit differently,
  > so please tell me if it matches what you are asking:
  > 
  > What is the best way to set-up a network of 10 million
  > nodes that all to need access both IPv6-only and IPv4-only
  > services?
  > 
  > There are two thoughts that I have about this question:

=> Good questions, I suggest we focus on those 
first then look at the different solutions.

  > 
  >          (1) It isn't a fully qualified question.
  >                  Further information is needed to
  >                  for a complete answer, such as:
  > 
  >                  - Do these nodes need continuous access
  >                          to IPv4 and IPv6 services, or only
  >                          occasional access?

=> I believe continuous access is needed. a PDP
context will be up when the device is turned
on and remain up pretty much the whole time. 
Some operators will configure things differently
(e.g. if idle for x hours remove PDP context), but
I believe people want to be "always on and connected"
(not meant to be a mrketing stunt!). This is simply
because once you lose your PDP context you're not
reachable.

  >                  - How many simultaneous IPv4 & IPv6
  >                          connections are expected?

=> Depends on the user, this is orthogonal to the 
PDP context(s).

  >                  - What is the planned internal structure
  >                          of the network?  Obviously you aren't
  >                          planning to bridge 10 million nodes
  >                          on a single subnet.

=> No.

  > 
  >          (2) Neither IPv4 nor NAT-PT will handle a 10 million
  >                  node network as a single address space.

=> NAT-PT can handle them in a single address space. Of course
not in a single box. 

  >                  The limitation of 32-bit addressing in IPv4
  >                  is a red herring, since the real limitations
  >                  on the size of a NAT based network is probably
  >                  much lower (a few hundred thousand simultaneous
  >                  connection?).

=> It's a 24-bit address space :) 

  > 
  > But, given that you've said this is a 3GPP network, I can
  > make some (perhaps flawed) assumptions about how this network
  > will be structured:
  > 
  >          (1) There will be internal routers (GGSNs) at a
  >                  density of one per ~100,000-500,000 nodes.

=> Correct.

  >          (2) All nodes will have point-to-point connections
  >                  to a single router (PDP Contexts to the GGSN).

=> correct.

  >          (3) The nodes will only need occasional access to
  >                  IPv4 & IPv6 services.

=> I think continuous accessibility is required.
We don't want to tear down PDP contexts and start
them again too often. 

  >          (4) IPv4 address configuration (and IPv6 address
  >                  configuration) of the nodes will
  >                  be performed on an as-needed basis
  >                  via the establishment of PDP contexts.

=> No, see above.

I will wait with the replies for the second part
of your email until we agree on the assumptions/scenario
first. I think this is very important and a great start
for detailed scenarios. 

Hesham