@karlauerbach@chris_bloke@glent@mattblaze Getting SIP security as good as possible was a continual challenge. As Security AD, I once blocked some RFC on security grounds, and had to defend my actions at a lunch surrounded by annoyed SIP folks. I had to pull out my laptop and show them exactly how the attack would work before they believed me. (It was, as I recall, a redirection request that was not properly authenticated.)
@SteveBellovin@chris_bloke@glent@mattblaze I have long considered SIP based VoIP to be vulnerable to the same kind of "route it through my country rather than yours" attack.
SIP is built to use proxies and it tends to use SRV records to find those proxies. If one gets hold of DNS in a way to forge those SRV responses, one can send the SIP data stream (typically RTP) via a spying proxy. Usually any encryption to the actual media stream is piecemeal source=>proxy=>proxy=>destination.
And watching the SIP headers, which also tend to be visible at proxies, opens the door to traffic analysis.
@chris_bloke@glent@mattblaze@karlauerbach So the British action in 1914 was actually the product of a strategy devised decades earlier. (Btw, Paul M Kennedy, Imperial Cable Communications and Strategy, 1870-1914, 86 English Historical Review 728 (1971), http://www.jstor.org/discover/10.2307/563928?uid=2&uid=4&sid=21103708309471 also has details, and for some folks is more accessible than Headrick's book.) Britain tried to route its communications through British-controlled territories, and tried to route other countries communications, too…
Napoleon famously kept the destination of his Mediterranean invasion fleet secret, to inhibit pursuit by the Royal Navy, with its faster warship-only fleet. Nelson sailed back and forth across the Med, catching news of where Bonaparte had been, only catching up with the French fleet after they had already disembarked Napoleon and his army in Alexandria, from where they rapidly conquered Egypt (a complex power play to separate India from Britian, the plunder of India paying for the British forces in the Napoleonic Wars).
Then, being Nelson, he wiped out the warships of the French fleet in the Battle of the Nile despite the French pre-prepared and advantageous position. (The streets of my Port Adelaide -- an Empire maritime town -- are named after this battle, it was widely admired as his technically best victory.)
Anyways, it's clear what a difference even one telegram could have made, and why the British Empire paid such large sums for undersea cables, initially of short life.
@SteveBellovin@karlauerbach Yes, I love the point about how they used to not bother keeping the movement of warships secret, since the news of the ship leaving port couldn't travel faster than the ship itself.
@karlauerbach@mattblaze You'd enjoy Standage's book, if you haven't read it. Briefly, his thesis is that the telegraph network was a bigger change in human society than the Internet, since it was the first way to communicate rapidly across very long distances.
I've long considered the electrical telegraph system to be the first electrical packet switching network. Telegrams are an analog to IP packets - and often several telegrams had to be assembled to form a more complete message - and telegrams were relayed, store-and-forward style. I do not know how the telegraph systems figured out telegram routing.
By-the-way, I have an interesting book from the Union Signal Company about the history of railroad signals. It's really a book about Murphy's law - pretty much everything that could have possibly gone wrong with signals has. at one time or another, gone wrong.