What email encryption is actually in use?
ptrei at rsasecurity.com
Mon Nov 4 08:27:50 PST 2002
> Tyler Durden[SMTP:camera_lumina at hotmail.com] writes:
> "Most the ones I've seen are IPSEC over IPv4. You might be able to glean
> some info from packet size, timing, and ordering, but not much. IPSEC
> takes a plaintext IP packet and treats the whole thing as a data block
> to be encrypted."
> SO this would indicate that IPSEC creates a sort of blockage from seeing
> to Layers 4/5/6. Now when you say it takes the IP packet, is this just the
> datagram or is it also he procotol bytes? (I'm assuming the layer-2
> information remains intact.) If the protocol bytes are unencrypted, then
> there's a LOT that can probably be determined about any IP session. If the
> protocol bytes are encrypted, then this will ot be a very flexible
> no? (More of a secure pipe I guess.)
> And then, does IPSEC include specification for MPLS? I would assume that
> MPLS header information is not encrypted, simply because the headers have
> global significance...
It's a pipe. The whole plaintext IP packet, from start to finish, including
headers and checksum, gets treated as data, and encrypted.
The encrypted packet is the data for a new packet, which goes from one
firewall to another (and has only the firewall IP addresses exposed). The
packets visible on the outside only tell Eve that firewall A sent firewall
B an IPSEC packet of a certain size, with a particular Security Association.
(ie, the protocol field says 'this is an IPSEC packet').
A single SA can be used for many, many, internal connections.
Check the IPSEC RFCs for more info.
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