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> The easiest thing for you to do is to get 2 internet connections from different carriers that do not share networks. This is not as easy as it may seem, as i

> The easiest thing for you to do is to get 2 internet connections from different carriers that do not share networks. This is not as easy as it may seem, as it's common for the carriers to lease from each other in the backbones. Telus and Bell for cellular services share a radio network, each cell site connects to both the Bell and Telus core networks. The big Bell backbone outage in the Toronto area, 6 or 7 years ago, had impacts on all of Bell, Telus, and Rogers networks. As for cellular services we had glitches nationwide that had to be fixed during that backbone outage.

icehawk 4y ago
And even if they don't share networks they might share physical space. I had an incident where two different trans-Atlantic links from two different providers, shared a 20 mile stretch of conduit. So, of course, that's exactly where the fiber cut happened.
bcrl 4y ago
In the case of the Rogers outage, other carriers / ISPs were not offline. The Rogers problem appeared to be entirely in L2/L3 -- switches and routers were not configured correctly. The other telcos were not impacted as they run their own routing infrastructure. Basically, make sure your 2 ISPs have their own ASNs and transit providers.
- kevin_nisbet 4y ago
  Sorry, I think you missed the point I was trying to share. The large providers all lease infrastructure from each other, so it's unsafe to assume that using two providers creates a total diversity in access. But you're correct, in that failures can happen at different layers, that may isolate outages to one provider or even a subset of customers. The outage I cited, only occurred in the Bell Wireline Core network, but caused service impacts in Bell, Telus, Rogers and other networks for Cellular, Internet, etc services.
  - bcrl 4y ago
    Again, it depends on what you're leasing from other carriers. Yes, if you're purchasing an L2 path from a carrier you're relying on their switches and routers to pass traffic correctly, but you bypass their routers and switches by purchasing an L1 wavelength circuit between 2 points. That's one of the main reasons that wavelength circuits are used (in addition to the guaranteed capacity). Third party carriers using fibre local loops from another carrier would not have gone down like TPIA users did on Rogers' network yesterday. I strongly believe that access to fibre local loops is needed in Canada. Leased copper local loops enabled plenty of competition between small local ISPs in the 1990s and early 2000s while they could still deliver speeds that were sufficient for internet users of the time. Having a tariff for local fibre circuits similar to the old LDDS tariff would bring back that vibrant competition we once had. Bonus: it's a lot harder for incumbents to put together bogus cost studies as compared to the failed disaggregated regime the CRTC has wasted nearly a decade on now.

icehawk 4y ago

And even if they don't share networks they might share physical space. I had an incident where two different trans-Atlantic links from two different providers, shared a 20 mile stretch of conduit. So, of course, that's exactly where the fiber cut happened.

bcrl 4y ago

In the case of the Rogers outage, other carriers / ISPs were not offline. The Rogers problem appeared to be entirely in L2/L3 -- switches and routers were not configured correctly. The other telcos were not impacted as they run their own routing infrastructure. Basically, make sure your 2 ISPs have their own ASNs and transit providers.

kevin_nisbet 4y ago
Sorry, I think you missed the point I was trying to share. The large providers all lease infrastructure from each other, so it's unsafe to assume that using two providers creates a total diversity in access. But you're correct, in that failures can happen at different layers, that may isolate outages to one provider or even a subset of customers. The outage I cited, only occurred in the Bell Wireline Core network, but caused service impacts in Bell, Telus, Rogers and other networks for Cellular, Internet, etc services.
- bcrl 4y ago
  Again, it depends on what you're leasing from other carriers. Yes, if you're purchasing an L2 path from a carrier you're relying on their switches and routers to pass traffic correctly, but you bypass their routers and switches by purchasing an L1 wavelength circuit between 2 points. That's one of the main reasons that wavelength circuits are used (in addition to the guaranteed capacity). Third party carriers using fibre local loops from another carrier would not have gone down like TPIA users did on Rogers' network yesterday. I strongly believe that access to fibre local loops is needed in Canada. Leased copper local loops enabled plenty of competition between small local ISPs in the 1990s and early 2000s while they could still deliver speeds that were sufficient for internet users of the time. Having a tariff for local fibre circuits similar to the old LDDS tariff would bring back that vibrant competition we once had. Bonus: it's a lot harder for incumbents to put together bogus cost studies as compared to the failed disaggregated regime the CRTC has wasted nearly a decade on now.