Using SS7 one can redefine routes, gather number translation info via Signalling Control Points (SCPs), etc. Rather than repeat boring details, check out: http://support.dialogic.com/ss7/SS7tutorial/tutorial.html The link is a brief tutorial on SS7; it'll make possibilities more obvious. What's the danger of SS7 over IP? Lack of security features at gateways and at the protocol level. pz
How does this improve eavesdropping? SS7 is only signaling. There is no voice payload on the SS7 network. SS7 simply passes signaling information around. Perhaps the knowledge of calling and called party since those digits are passed via SS7 but the converstation is entirely distinct.
-jr
-----Original Message-----
From: owner-cypherpunks@Algebra.COM
[mailto:owner-cypherpunks@Algebra.COM]On Behalf Of Josh Richards
Sent: Tuesday, January 09, 2001 9:35 PM
To: cypherpunks@einstein.ssz.com
Subject: SS7 over the Net (was Re: History Channel television show on
NSA)
* Phillip Zakas
BTW, has anyone heard of recent moves to push SS7 phone messaging traffic over the internet in a bid to boost scalability and LNP resolution speeds?
Three effects: it'll work better than the current SS7 network alone; improved eavesdropping on conversations which touch land lines (fyi only phone-to-phone cell phone comms like nextel's two-way-radio feature don't use land lines I believe); decreased need to try to decipher the message while it's in the air (it's harder to intercept over the air
There are already carriers doing SS7 over IP via gateways. Over the public
Internet is not a stretch from a technical standpoint but, in practice,
I'd find it hard to believe too many LECs or IXCs going this route. Private
IP networks, yes already in production even. The public IP network, nobody
serious is doing it. Wait, well, if you just mean VoIP there are VoIP
companies that are attempting things like this by partnering with regional
and local ISPs to place voice gateways. If you're talking governmental
moves, there are easier ways. The SS7 network isn't exactly encrypted..
transmissions).
How does this improve eavesdropping? SS7 is only signaling. There is no
voice payload on the SS7 network. SS7 simply passes signaling information
around. Perhaps the knowledge of calling and called party since those
digits are passed via SS7 but the converstation is entirely distinct.
-jr
----
Josh Richards [JTR38/JR539-ARIN]