[WireGuard] WireGuard cryptokey routing

[Norman Shulman]

Look at it from the server side. There are millions of clients on millions
of 192.168.1.0/24 networks, yet a server can communicate with no more than
254 of them.


On Wed, Jul 6, 2016 at 11:48 AM, Baptiste Jonglez <
baptiste at bitsofnetworks.org> wrote:

> On Wed, Jul 06, 2016 at 11:31:28AM -0400, Norman Shulman wrote:
> > Ethernet networks don't scale; that's why we have IP networks.
>
> Wireguard does not use Ethernet at all, it operates purely at layer 3 (IP).
>
> IP over Ethernet would use a reactive scheme (ARP, Neighbour Discovery) to
> discover the mapping between IP addresses and link-layer addresses.  This
> is part of the reason why Ethernet does not scale well.
>
> Wireguard, on the other hand, does the equivalent mapping statically, via
> the AllowedIPs directive.  The mapping is also slightly different:
>
> - with Ethernet, you map from IP address to MAC address (using ARP or ND)
>
> - Wireguard maps from IP address to public key (using AllowedIP, so this
>   is completely static).  A public key is then mapped to the IP address
>   and UDP port of the peer on the Internet, using the last known endpoint
>   of the peer.  This makes this second mapping mostly dynamic, even though
>   it falls back to a static "Endpoint" configuration for bootstrap.
>
> Does that make things clearer for you?
>
> > So in general a client needs one address for each server? Rather limiting
> > for clients on small subnets, especially considering the case of n
> clients
> > on a subnet, each connecting to m different servers.
> >
> >
> >
> >
> > On Tue, Jul 5, 2016 at 3:11 PM, Jason A. Donenfeld <Jason at zx2c4.com>
> wrote:
> >
> > > On Tue, Jul 5, 2016 at 9:09 PM, Norman Shulman
> > > <norman.shulman at n-dimension.com> wrote:
> > > > How is this enforced?
> > > Receiving, line 238 here:
> > > https://git.zx2c4.com/WireGuard/tree/src/receive.c#n238
> > > Sending, line 112 here:
> > > https://git.zx2c4.com/WireGuard/tree/src/device.c#n112
> > >
> > > > How does this scale?
> > > The same way in which an ethernet network scales? One ethernet device
> > > can have multiple IPs, but separate (unbonded) ethernet devices
> > > generally do not share IPs.
> > >
>
> > _______________________________________________
> > WireGuard mailing list
> > WireGuard at lists.zx2c4.com
> > http://lists.zx2c4.com/mailman/listinfo/wireguard
>
>


-- 
Norman Shulman
Sr. Developer/Architect
N-Dimension Solutions Inc.
9030 Leslie St, Unit 300
Richmond Hill, ON L4B 1G2
Canada

Tel: 905 707-8884 x 226
Fax: 905 707-0886

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