Hi,

On Wed, 19 Feb 2014 21:57:26 +0100
Daniel Migault <[email protected]> wrote:

> On Thu, Feb 6, 2014 at 11:07 AM, Timo Teras <[email protected]> wrote:
> > On Thu, 6 Feb 2014 09:20:08 +0100
> > Daniel Migault <[email protected]> wrote:
> >
> >> RFC5685 is not limited to client-gateway, the second line of the
> >> section 10 you pointed out says: [...] the mechanism can also be
> >> used between any two IKEv2 peers. " So no additional specification
> >> are required.
> >
> > You missed the next sentance:
> > "However, the mechanism can also be used between any two IKEv2
> > peers. But this protocol is asymmetric, meaning that only the
> > original responder can redirect the original initiator to another
> > server."
> >
> 
> Suppose A establish an IPsec session with node B. B can use a Redirect
> not A. If A has not the capacity to handle the communication it should
> not initiate it, and let C initiate the communication. This may be a
> disadvantage is A and B are "equal", but in that case A and B should
> be organized as clusters and redirect may not be the best way.

But if A original had the capacity and was intended to establish it,
but then later on routing protocol or administrative action made the
prefix to be removed from A. A would then need to inform of this
somehow.

> >> You mention load balancing may be an issue. Can you please specify
> >> the issue you see?
> >
> > Could you specify how in practice I could implement one subnet to be
> > load-balanced to spoke nodes?
> >
> If I correctly understand your scenario, you are looking at load
> balancing the traffic of your private network between two spokes. Any
> IP-load balancer could split and load balance the traffic between the
> two spokes.
> On the other hand you might also want to have multiple spokes under a
> given IP address. In that case, load balancing is performed according
> to the hash of the IP addresses or according to values of the SPI.
> Solution like cluster IP load balance the traffic between the two
> spokes [1].
> 
> [1]
> http://wiki.strongswan.org/projects/strongswan/wiki/HighAvailability

This generally works by requiring single virtual IP that is then later
on load-blanced.

How about I have two ISP connection with separate public IPs. Haw can I
loadbalance over them? This is relatively simple to achieve in DMVPN.

> >> One last point to clarify. it seems that you are trying to say
> >> ADVPN misses some features provided by routing protocols. In fact
> >> ADVPN can take advanatge of ALL of these features as ANY routing
> >> protocol can run on the top of ADVPN. This was a MUST requirement
> >> of RFC5685. If you see a scenrio that you think does not fit
> >> ADVPN, please document it so we can address your specific issue.
> >
> > I thought the advantage was to _not_ run routing protocol.
> 
> You are right ADVPN does not necessarily need routing protocol. It can
> have one or not, it is up to the scenarios you want to address.
> 
> > If running  routing protocol is supported, can you please specify
> > how a routing protocol is to be integrated with the IKE traffic
> > exchange? Yes, it is possible, but non-trivial, thus I would like
> > to see some specification mapping how to do that mapping.
> 
> I do not see the issue. Can you point out the issue more specifically.

There is a lot of things involved. First question is already explained
in this (see above) and the previous mails. What happens when routing
protocol withdraws a subnet from one gateway, and it needs to tell
everyone that it's no longer available from it, but may be available
through other nodes.

> > And like someone else asked, how is MPLS routed?
> 
> Maybe you could encapsulates MPLS traffic in GRE/IP. Everything
> possible with DMVPN is possible with ADVPN.

This is one step closer to dmvpn. But how would the SHORTCUT mechanism
work then? 4.1. says protected domain can contain only
INTERNAL_IP4_SUBNET (13) and INTERNAL_IP6_SUBNET (15).  You'd need to
specify additional record types to all possible protocols ever needed
to run over GRE.

_______________________________________________
IPsec mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/ipsec

Reply via email to