yet another reason
to use a VPN service.
Another of the submarine cables connecting Australia to the world, for data, has broken. PPC-1, which stretches from Sydney to Guam and has 1.92 terabits per second capacity, is out of service until at least March 7. TPG's announcement says the fault is around 4,590 km from the cable's Guam landing, which means it's around 3, …
The problem is with the TPG owned cable. If you connect to a VPN endpoint in Australia (mine has Sydney or Melbourne options), your traffic that would ordinarily travel across that cable won't. It will go via the VPN provider infrastructure from that point onwards.
Won't help you in Tassie obviously.
I think the point is that routing metrics may not take congestion into account. If you run a VPN terminating across a different cable, you prevent your traffic from hitting the congested cable.
So rather than jam the trans-pacific link, you go via Asia/Europe - more hops and higher latency but far less congestion/packet loss, and therefore a better route.
What we are actually talking about is reduced capacity on one link from a multi-link site, not a complete link loss on a stub network.
To show the doubters out there, here are the first 7 hops with and without VPN (pia in this case) over tpg to NASA.gov . The exercise is left to the reader to work out how these are routed, but the participation of trunk links via Kenya and the involvement of Swiss ISPs should give you some hints.
1. 192.168.0.1; www.routerlogin.com; 2.069, 4.426, 4.576
2. 10.20.xxx.xxx; 21.066, 23.260, 24.255
3. 202.7.xxx.xxx; 202-7-xxx-xxx.tpgi.com.au; 25.745, 28.481, 28.636
4. 220.127.116.11; syd-sot-ken-int1-be-20.tpgi.com.au; 30.506, 33.322, 34.271
5. 18.104.22.168; las-b3-link.telia.net; 208.953, 212.432, 212.689
6. 22.214.171.124; las-b21-link.telia.net; 211.422
6. 126.96.36.199; las-b21-link.telia.net; 211.839
6. 188.8.131.52; las-b21-link.telia.net; 210.804
7. 184.108.40.206; dls-b21-link.telia.net; 237.292
7. 220.127.116.11; dls-b21-link.telia.net; 222.407
7. 18.104.22.168; dls-b21-link.telia.net; 223.347
1. 10.113.xxx.xxx; 21.241, 23.388, 24.962
3. 22.214.171.124; 326.402
3. 126.96.36.199; 313.348
3. 188.8.131.52; 314.520
4. 184.108.40.206; 326.518
4. 220.127.116.11; 317.522
4. 18.104.22.168; 317.991
5. 22.214.171.124; ae7.amster32.ams.seabone.net; 324.957, 337.009, 329.025
6. 126.96.36.199; xe-1-0-0.ashburn2.ash.seabone.net; 416.610
6. 188.8.131.52; xe-0-2-0.ashburn2.ash.seabone.net; 402.819
6. 184.108.40.206; xe-1-2-0.ashburn2.ash.seabone.net; 404.017
7. 220.127.116.11; amazon.ashburn2.ash.seabone.net; 474.928
7. 18.104.22.168; amazon.ashburn2.ash.seabone.net; 450.211
7. 22.214.171.124; amazon.ashburn2.ash.seabone.net; 454.509
So is this difference academic or are there real world implications? The answer of course is that it depends. For browsing it is pretty minor. Throughput is limited by my ADSL2 which is in about the worst possible place relative to the exchange. It is measurable but for the most part feels normal. I did a speedtest from a few places. The most noticeable difference was via Seoul where the VPN was nearly 100ms FASTER in the ping test than no VPN.
This is hardly surprising given the detour that the packets are taking. Unless the packets between your home an the VPN endpoint are traversing via Guam, or the backbone of your VPN provider is carried via tpgs private cable, then a break in that said cable isn't going to affect you. Tpg have two choices here. They can route around the fault by using their other cables (as they did in the traceroute above) or they can buy additional capacity from their competing northbound fibre links. No doubt they will be doing both at different times but a lot of that capacity (on competing links) would have been bulk purchased so it isn't always available and unlikely to be cheap.
Not by any means a telco specialist, so honest question:
Has a multi-hop microwave link from the mainland ever been considered? Line of sight should work, IIRC - say, Southern tip of VIC, King Island, northern TAS.
Even if just for backup purposes such as this.
Are there technical/financial/environmental issues why this wouldn't work?
Years ago I was looking at some calculations of the line of sight "hill" due to earth curvature between Victoria and Tasmania and it it was something on the order of 400 meters tall. With microwave, you also have to keep things out of the Fresnel zone as well. Undersea cable is about $10 per meter and you can put down cable cheaper than you can build tall towers in prime real estate which is considered environmentally sensitive. An old aviation chart shows that there is a 4,000 ft obstacle near Flinders island so I expect Telstra already has a microwave link going that way. I know when a betting shop opened up there about a decade ago, they had asked for 2 gigabit links and that was the entire capacity at the time.
Microwave links need line of sight. Oceans are the reason we started building satellites...
Also, microwave data links simply cannot carry as much data as a decent fibre optic cable. The bandwidth is not available. That's why microwave links have mostly gone out of fashion.
They've come back into fashion a little bit in the USA. A financial institution in Chicago built a private microwave relay chain all the way to New York. Why? The latency on a microwave link is a lot lower than on a fibre (microwaves travel at c, light in a fibre travels at 0.6c). That matters if you're in the high speed share trading business. This link knocks approx 2milliseconds off the time taken to make a trade.
There have been microwave links from mainland Oz to Tassie since 1959. One was from Mt Oberon on Wilsons Prom, via Mt Tanner on King Island, to Waterhouse. The other was from Cape Otway, via Grassy on Flinders Island, to Cape Grim (Woolnorth). I think that they are no longer in use as Telstra has the Bass Strait 1 fibre cable operating since 1995 and Bass Strait 2 operating since 2003.
Basslink is not the only comms link to Tassie.
Looking at a submarine cable map, I see that Australia still has a few other cables left. Also, there are one or more cables linking it to Papua New Guinea, which is closer to Asia. But what surprises me is that none of those cables enter the ocean from Cape York, which would allow them to be shorter.
As Papua New Guinea is administered by Australia, it would seem that they're missing an opportunity to shorten the length of Australia's submarine cable links to the outside world; those links could go to PNG and then continue on from it to Australia.
Also, I read an interesting report on the web that notes that New Zealand takes the protection of its submarine cables more seriously than Australia.
Firstly, PNG is independent of Australia, has been since 1975.
Secondly, the broken PPC1 cable in question that Australia uses to connect to Guam is also connected to PNG, via the Solomon Sea. Cables don't go overland in PNG - nothing does. It's bloody tough country, with over 4000m mountains in the middle.
Most of the connections go via the Sunda Straight to Jakarta and Singapore, because that's the easiest and cheapest way to tap into the big asian pipelines, and has the least exposure to the really complicated and fairly shallow seafloor between Kalimantan and PNG which is full of volcanic activity.
They are very vulnerable to a big bang from Krakatoa, but the costs of rebuilding are probably less than running new cables to Sri Lanka.
Lastly, NZ has a *really* active plate boundary running along the east coast, which is why the Southern Cross is the only cable to be routed that way, and it runs up to Hawaii parallel to the boundary to avoid the trenches. Every other link goes via Australia and the Tasman Sea is geologically stable.
I believe, but without knowing anything about the intricacies of U-boat special operations (where is Lewis when you need him?) that the Americans may have a publicly funded vessel suited to such work. Perhaps they'd help out an ally, although I accept this is a private commercial issue rather that a "state" problem, although the effects might be of national importance for things like the economy etc.
If not, then a few lines from Not the Nine O'clock News song "All Out Superpower Confrontation" come unbidden to mind, apologies to anyone finding the connection a little obscure (including just about anyone under 45):
Jimmy Carter must have known, That's why he stayed at home...
Icon purely for the song
you don't repair at depth
you cut the cable at two accessible locations, lifting the two landward "ends" to the surface, splice in new cable on the surface then let it drop
problem is you can't put the repair into a trench: it just sits on the sea bed more vulnerable than before as originally it WOULD have been trenched
Biting the hand that feeds IT © 1998–2019