Class E addresses in the wild

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1

Is anyone else seeing a lot of Class E address space (240.0.0.0/4) at their
borders? Has this space been reinstated in some as yet unknown to me RFC?
Thanks,
Buz

2

Is anyone else seeing a lot of Class E address space (240.0.0.0/4) at their
borders?

I'd put those is in the martian category.

  Has this space been reinstated in some as yet unknown to me RFC?

No it hasn't.

3

No authorized IETF use that I know of. See
http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xml

Thanks,
Donald

4

It is (or was) fairly commonly in use among internal nets which
overflowed RFC 1918 or have to internetwork with other heavy users of
RFC 1918 space. I know of at least two service providers and one cell
network who were using it for that 3 years ago.

Someone leaking internal routes for such? Or attempt to hijack the space?

Only the Shadow knows...

5

It is (or was) fairly commonly in use among internal nets which
overflowed RFC 1918 or have to internetwork with other heavy users of
RFC 1918 space. I know of at least two service providers and one cell
network who were using it for that 3 years ago.

I am pretty sure Class E is completely defunct and not used anywhere
since Cisco and Juniper routers do not forward the packets (circa 2008
testing) and no known host accept it as a valid address, AFAIK.

CB

6

Both the net and host sides of this are trivially repairable problems,
even for crazy cellphone network operators. As long as you have host
source code and a network vendor you can demand custom patches
from....

7

It's in our Martians ACL but we left it off of a couple of new border
connections and saw a good bit of it forwarded to us since Wednesday from
multiple ISPs.
Fixed now but still curious.
Thanks,
Buz

8

Fiserv uses this address space for their ATM network.