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10 gigabit Ethernet 80 GHz point-to-point bridges

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21–30 of 94 posts

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#21
post #15

It's interesting to see the huge channel bandwidths they're using to attain this. Advances like this are largely driven by higher sample rate ADCs and DACs becoming more viable in recent years. Edit for clarity: channel bandwidths in the datasheet are up to 2 GHz. Need to close the link at 32 QAM to hit 10 gb before error correction overhead at that bandwidth, which is certainly doable. Also, it's interesting to note…

>higher sample rate ADCs and DACs becoming more viable

Question, on optical networks doesn't this make dispersion more of a problem?

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#23
post #8
post #2

• Secure communication due inability to intercept the laser-like beam transmission at free air I would not trust that as a security layer.

It's definitely not something to trust in, but intercepting (at a layer 1 level) a PTP 80 GHz link is actually harder than tapping fiber. You'd have to have Rx equipment either directly in the path or directly behind both ends of the radio link. As compared to the effort required to cut an aerial or underground singlemode cable and fusion splice in place a passive prism split tap (basically the same thing as insertin…

On a fiber you don't need downtime at all. If you manage to carefully clean the fiber from isolation and buffer and then bend it just enough to leak some light into yours.

So, assume that everything might be tapped and encrypt your data.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#24

The word "Ethernet" in the title is misleading. That word does not appear in TFA, which appears to discuss a radio transceiver. [EDIT:] I stand corrected; thanks!

They're transparent Ethernet bridges. They have Ethernet interfaces, you push an Ethernet frame in one side and the same Ethernet frame comes out the interface on the other side.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#25
post #2

• Secure communication due inability to intercept the laser-like beam transmission at free air I would not trust that as a security layer.

I haven't read the datasheet on this particular radio, but a lot of them do optionally support AES encryption (sometimes as an extra, paid feature).

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#26
post #8

Earlier quoted context omitted.

It's definitely not something to trust in, but intercepting (at a layer 1 level) a PTP 80 GHz link is actually harder than tapping fiber. You'd have to have Rx equipment either directly in the path or directly behind both ends of the radio link. As compared to the effort required to cut an aerial or underground singlemode cable and fusion splice in place a passive prism split tap (basically the same thing as insertin…

On a fiber you don't need downtime at all. If you manage to carefully clean the fiber from isolation and buffer and then bend it just enough to leak some light into yours. So, assume that everything might be tapped and encrypt your data.

Yes, or if your fast, cheap new metro ethernet 10GbE circuit between two buildings has been provisioned by your ISP as some form of transport (handoff into a WDM system, EoMPLS tunnel), etc, it's not difficult for them to 'mirror' your port. It could be pre-tapped before it was ever turned up for customer service.

Or the splitter could be installed in your riser cable at one end, before you ever started moving packets across it.

Or a myriad of other things.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#27
post #8
post #2

• Secure communication due inability to intercept the laser-like beam transmission at free air I would not trust that as a security layer.

It's definitely not something to trust in, but intercepting (at a layer 1 level) a PTP 80 GHz link is actually harder than tapping fiber. You'd have to have Rx equipment either directly in the path or directly behind both ends of the radio link. As compared to the effort required to cut an aerial or underground singlemode cable and fusion splice in place a passive prism split tap (basically the same thing as insertin…

I recall reading about Soviet spies buying a cabin close to the AT&T long lines microwave path to intercept calls & fax transmissions in the 60s or 70s.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#28
post #14

Earlier quoted context omitted.

If you've got line of sight then current (cheap) tech should do just fine. Sure not 10x gigabit but you can def get some decent internet...

Do you have any recommendations for current products for line of sight?

I don't have any first hand experience, but I know you can do long range (couple kilometers), reliable (for consumer level) decent speed links for dirt cheap (Detour paragraph - background - Internet has historically been pretty sht in South Africa so a enthusiast spider network of point to point links sprung up much like the ham radio movement. Government decided to OK it as long as its not commercial & doesn't deliver internet services.

Anyway...the WUG websites (JAWUG, PTAWUG, CPTWUG - being Johannesburg/Pretoria/CapeTown) have lots of beginner style info on it (will trees and leaves in block it etc)...plus info on cheap kits...plus there are loads of people there that know this stuff in wild detail (as I said - 100% community driven so even the central high-sites are community run).

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#29
Interesting.

There has been a huge effort in the UK for mobile carriers to add fiber to as many cell towers as possible.

Do people think this would undo this trend? I'm sure that 10gbit would be more than enough to carry the backhaul of 3G+4G with plenty of room to spare?

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#30

Interesting. There has been a huge effort in the UK for mobile carriers to add fiber to as many cell towers as possible. Do people think this would undo this trend? I'm sure that 10gbit would be more than enough to carry the backhaul of 3G+4G with plenty of room to spare?

not really, fiber is still greatly preferred (For example: it's impossible to do 40Gb by microwave/millimeter wave, but a CWDM 4-channel 4x10GbE passive mux/demux on two strands of singlemode is trivial and very very cheap), or just a pair of 40Gb QSFP 10km reach optics using a single 1550nm wavelength between two routers or metro-E switches. But wireless can reach small cells, rooftops and towers that might be a very costly underground fiber build at $400-900/meter total construction cost to dig up streets in urban cores. It very much depends on the location.
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