Wake on LAN in the enterprise

Fri Dec 24 04:41:06 UTC 2010

On 12/13/10 8:32 AM, Jack Bates wrote:
> On 12/13/2010 10:20 AM, Owen DeLong wrote:
>> WOL is unfortunately terribly deficient in that the spec. never
>> envisioned the possibility
>> of a need for wake on WAN.
>>
>> Bottom line, it's a non-routeable layer 2 protocol. Your choices boil
>> down to the
>> helper address nightmare you describe or proxy servers on every subnet.
>>
> 
> I would suspect that proxy servers being the better deal, though my
> experience with Cisco is that you may have to use ASR type gear to get a
> nicer layout (similar to service providers) where you can backend
> everything to a radius server (I'm still waiting to test this myself,
> but IOS is really weak on DHCP support).

assuming you don't mind burning an ip address per subnet you can do this
with a static arp entry for an ethernet multicast address even if your
l3 platform doesn't allow subnet directed  multicast.

on a firewall platform basied on linux I specifically worked around the
deliberate lack of subnet directed broadcast by natting from the
broadcast address of the target subnet to an rfc 1918 address on the
subnet with a static arp entry pointing at a multicast address. it
worked fine, exploited the fact that rewrite occurs before forwarding on
linux and allowed the use of a pre-existing management tool that used
subnet directed broadcasts.

> 
> Jack
> 