critical WPA2 vulnerabilities afoot, see KRACK attacks (discussion @ /r/KRaCK, HN, /r/netsec, Slashdot)

Talk:Linksys WRT1900AC v2

From WikiDevi
Jump to: navigation, search

WRT1900AC-V2 CPU clockspeed and the WRT1900ACS


Hi,


I own a WRT1900AC-V2 for about a week now and have been doing some digging into the hardware it uses especially regarding the hardware, it's CPU, clock-speed and performance. I've done what i think are some noteworthy findings that i would like to add to Wikidev.


Now, as we all know, Linksys 'advertises' the WRT1900AC-V2 as having a "1.3 Ghz dual core" CPU. It is printed on the Box the WRT1900AC-V2 is sold in (as one of the photos in this Linksys forum-topic show) this photo, portraying the back of the Box of the WRT1900AC-V2, also clearly shows the processor being referred to as a "1.3Ghz dual core" CPU.

Linksys also writes (on it's Canadian support page) that: "The Linksys WRT1900AC v2 is powered by a Dual-Core 1.3 GHz CPU".

Despite of the claims Linksys makes regarding the CPU of the WRT1900AC-V2, it is actually clocked at 1600Mhz, in fact the hardware of the WRT1900AC-V2 is identical to that of the WRT1900ACS.

===================================================================================================================================================================================[edit]

About the CPU and it's clock-speed:


WRT1900AC-V2 Performance in BogoMIPS:

When i installed DD-WRT on my WRT1900AC-V2 the web-interface showed the CPU is clocked at 1600Mhz.

After i installed OpenWRT on the WRT1900ACv2 I logged in to the router via SSH I then ran the "cat /proc/cpuinfo" and got the following output: Screenshot 2015-10-17 17-10-31.png

Note that the number of BogoMIPS for both processor cores is 3188.32.

The BogoMIPS score of the WRT1900ACv2 is 20% higher than that of the Linksys WRT1200AC router, the number of BogoMIPS the CPU-cores of the WRT1200AC is rated at is 2655.84 BogoMIPS. Now, the WRT1900AC-V2 supposedly (according to Linksys) uses the same 1.3Ghz CPU as the WRT1200AC does yet the WRT1900AC-v2 is 20% faster in terms of BogoMIPS. The score in BogoMIPS of the WRT1900AC-V2 corresponds to the 20% higher clock-speed of the CPU in the WRT1900AC-V2 compared to the WRT1200AC's CPU @ 1.3Ghz.


WRT1900AC-V2 performance in OpenWRT OpenSSL Benchmark:

I've ran the OpenSSL benchmark available with OpenWRT on the WRT1900AC-V2 (a single core was tested and no ASM was used).

I've created a pastebin file with the results here and have added the results to the benchmark table at the OpenWRT-Wiki page regarding the OpenSSL benchmark.

Here's a comparison of the results of the WRT1900AC-v2 with the WR1200AC:

WRT1200AC----- | 1.0.2d | 130332670 | 33454080 | 27113470 | 11221330 | 14561960 | 5196800 | 23971500 | 20780030 | 18331650 | 26.8 | 972.7 | 94.5 | 78.7 |

WRT1900AC-V2 | 1.0.2d | 157197990 | 40096090 | 32472410 | 13493170 | 17463300 | 6236160 | 29265170 | 25055570 | 22668290 | 32.0 | 1163.9 | 113.0 | 92.1 |


Difference % --- | +20% | +19% | + 19% | +20% | +19% | +20% | +22% | + 20% | +23% | +19% | + 19% | + 19% | +17% |

As you can see the the WRT1900AC-V2 scores are 20% higher than the WRT1200AC. These results indicate that the processor of WRT1900AC-V2 is clocked 20% higher than that of the WRT1200AC

Actual proof of the clockspeed of the CPU and DDR-RAM:

The BogoMIPS score and OpenSSL result provide circumstantial evidence that the CPU of the WRT1900AC-V2 is clocked @1600Mhz. Luckily debugfs is enable with OpenWRT 15.05 build for the WRT1900AC-V2 so we can query the clock-speed of both the CPU and DDR-RAM as the following screenshot shows:

Scrnshot-2015-10-15 16-20-26.png

So there you have it, the clock-speed of the WRT1900AC-V2 is indeed 1600000000 hertz or 1600 megahertz. The speed of the RAM is 800000000 hertz or 800 megahertz.

Furthermore a member of the DD-WRT forum has provided part of the U-Boot bootlog of his WRT1900AC-V2:

     Board: RD-NAS-88F6820-DDR3 
SoC: MV88F6820 Rev A0 running 2 CPUs CPU ARM Cortex A9 MPCore (Rev 1) LE CPU 0 CPU @ 1600 [MHz] L2 @ 800 [MHz] TClock @ 200 [MHz] DDR @ 800 [MHz] DDR 32 Bit Width, FastPath Memory Access, DLB Enabled, ECC Disabled DRAM 512 MiB

(source: http://www.dd-wrt.com/phpBB2/viewtopic.php?p=987757#987757)

The U-Bootlog provides more proof that the CPU in the WRT1900AC-V2 is clocked @1600Mhz and the RAM is clocked @800mhz.

The FCC documentation (internal photos of the WRT1900AC-V2) also showed that the WRT1900AC-V2 uses a Marvell "88F6820 C160" CPU which is the 1.6Ghz version of this chip.


The WRT1900AC-V2 and the WRT1900ACS

The WRT1900AC-V2 uses a 1.6 Ghz processor and has 512MB RAM, just like the WRT1900ACS, the actuall specs of both devices are the same.

The WRT1900ACS has the same FCC-ID as the WRT1900AC-V2, (both have the following ID Q87-WRT1900ACV2) The WRT1900ACS was never certified as a different model but as the WRT1900AC-V2, indicating that they use identical hardware. After all if the WRT1900ACS would have used different hardware, Linksys would have to get the model certified and it would have gotten a new FCC-ID.

Also, Tim Higgins of networking / techwebsite Smallnetbuilder has written the following when the WRT1900ACS was announced:

"Linksys has updated its top-of-line AC1900 class router.

Linksys today announced the WRT1900ACS Dual-Band Gigabit Router. This is the same WRT1900AC V2 outed via firmware release notes back in April. The ACS replaces the AC, which will be gone when the last one is sold."

The same Tim Higgins when reviewing the WRT1900ACS reiterated this:

"Linksys' WRT1900ACS Dual-Band Gigabit Router is the official name for the WRT1900ACV2 that was outed via firmware release notes back in April. The ACS replaces the original WRT1900AC, which will be gone when the last one is sold. "


The WRT1900ACv2 and WRT1900ACS use the same hardware, the WRT1900ACS is just a rebadged WRT1900ACv2!



Editing Wikidev to show the correct CPUspeed


I would like to edit the Wikidev pages of the WRT1900AC the WRT1900AC-V2 and WRT1900ACS so those pages show the correct clockspeed etc... If anyone has objections against that, please make them known to me

Giraffe

WRT1900AC v2[edit]

The manufacturer has the right to change product specifications without notice at any time.
Next release another revision of the product and its packaging indicates new specifications.

WRT-1900ACv2 BackofBox.jpg

Perhaps that was just the factory firmware contains the lower processor speed for testing.
The new version is now officially confirmed WRT1900ACS "overclock" the processor up to 1.6 GHz.
  • P.S. We will adhere to the formal characteristics specified by the manufacturer.

-- Omega (talk) 22:31, 17 October 2015 (EDT)


My guess is that The WRT1900AC-V2 was using a 1.6Ghz processor from the beginning. But since the WRT1900AC-V2 was sold as as a WRT1900AC (product code is the same as WT1900AC) and prices of the WRT1900AC have dropped since its first introduction, it made more sense to sell the router as a "new", much faster, and different model, that model being the WRT1900ACS. That way they could price the router higher.

To stop people from buying the WRT1900AC-V2 (which has the same specs as the WRT1900ACS but is 25% more expensive (at least in Europe)) instead of the WRT1900ACS they lowered the specs that are printed on the packaging.

I'm new here, you clearly have a lot of experience as a editor, so if you say Wikidev will adhere to the formal characteristics specified by the manufacturer I will too.


--Giraffe (talk) 07:08, 18 October 2015 (EDT)