Recently, I bought a Asus RT-AC51U for Android USB tethering and 5GHz features. I also bough some new wireless USB device. Two D-Link DWA-171 A1 are for Mac mini and NAS. One D-Link DWA-131 E1 is for Lenovo C440.

Because DWA-171 A1 is compatible with OSX, Windows Server 2012 R2, and QTS but DWA-131 E1 isn’t for QTS, I decide to test wireless transfer between Mac mini and two NAS.

Asus RT-AC51U

WikiDevi is a good source to know more about your router. But the internal search tool is always missing, I suggest to use Google with site:wikidevi.com to search within WikiDevi or just edit URL directly.

According to ASUS RT-AC51U on WikiDevi, some important features include:

Because it has 2×2:2 2.4GHz antennas, 802.11n at 2.4GHz is up to 300Mbps.
Because it has 1×1:1 5GHz antenna, 802.11n at 5GHz is up to 150Mbps while 802.11ac is 433Mbps.
802.11n at 2.4GHz is handled by MediaTek MT7620.
802.11n at 5GHz and 802.11ac are handled by MediaTek MT7610E

About 2×2:2, the first number means there are 2 antennas for transmitters (TX), the second is 2 antennas for receivers (RX), and the last number is up to 2 spatial streaming. A more detail explanation may be found in 802.11n on The Cisco Learning Network and 無線網路新趨勢–漫談 802.11ac 新協定 on NTU.

D-Link DWA-171 Rev A1

The H/W ver: A1 is very important information but only show on a small label on the package or the last few characters of P/N on the device. Different hardware version might use different chips result in different performance and comparability.

According to D-Link DWA-171 rev A1 on WikiDevi, some important features include:

Realtel RTL8811AU supports draft 802.11ac which is not 802.11ac.
Max speed for 802.11n is 150Mbps with 1T1R.

It works on OSX, Windows Server 2012 R2, and QTS.

D-Link DWA-131 Rev E1

The H/W ver: E1 is very important information but only show on a small label on the package or the last few characters of P/N on the device. Different hardware version might use different chips and result in different performance and comparability.

According to D-Link DWA-131 rev E1 on WikiDevi, some important features include:

Realtel RTL8192EU supports 802.11n.
Max speed for 802.11n is 300Mbps with 2T2R.

It works on OSX and Windows Server 2012 R2.

Thecus W5000 with Windows Storage Server 2012 R2 Essential

W5000 uses an Intel Atom D2550 which is a 1.86GHz dual-core processor with Hyper-Threading Technology. It has 1MB L2 cache, Intel 64 Architecture, and supports up to 4GB DDR3.

The test machine comes with 2GB of DDR3 RAM and is upgradable. It also comes with a Seagate Laptop Thin SSHD 500GB as a system drive.

I install two Seagate Barracuda Desktop HDD as RAID 1 in it.

Windows Storage Server 2012 R2 Essentials is a x64 Windows based on Microsoft Windows Server 2012 R2. In specification tab of Thecus W5000, you will see a comparison table of Workgroup, Standard, and Essentials. Essentials doesn’t support Hyper-V but is capable of being a Domain Controller of Active Directory.

Although WSS 2012 R2 Essentials is a x64 Windows, it is limited to 4GB of RAM due to processor architecture. Memory Limits for Windows and Windows Server Releases on Microsoft provides a clear explanation.

Both DWA-171 rev A1 and D-Link DWA-131 rev E1 are working properly.

QNAP TS-119PII

TS-119PII uses a Marvell 88F6282 which is a single core ARMv5TE-compliant 32-bit processor with 256K L2 cache.

It comes with 512MB RAM and is not upgradable.

I install a single Seagate Barracuda Desktop HDD 500GB in it.

QTS is an embedded Linux developed by QNAP. This report test with 4.2.1 build 0217.

Compatible/Incompatible USB Wireless on QNAP Wiki contains a full list of known compatible/incompatible USB wireless. DWA-171 rev A1 is identified and working properly but only for 2.4GHz. It doesn’t work on 5GHz. Therefore, the max speed is 150Mbps. DWA-131 rev E1 is not compatible and therefore not identified by QTS.

Mac Mini Late 2012

I have upgrade my Mac mini to 16GB RAM and use a Seagate Laptop SSHD 1 TB which spins at 5400rpm and comes with 8GB MLC cache build-in to replace the slow hard drive.

According to System Information and macg.co：Mac mini (Late 2012)は11n/450Mbps/3ストリームに対応している on MACお宝鑑定団, the build-in AirPort Extreme 802.11n is based on Broadcom BCM43xx which is capable being up to 450Mbps at 5GHz on 40MHz bandwidth using 3×3:3. I am not sure if 2.4GHz may support up to 450Mbps yet.

But there is one problem: the connection speed is 150Mbps with RT-AC51U at 2.4GHz. According to OSX Yosemite Wifi issues on apple support, it seems related to OSX 10.10. Only getting connection speeds of 130 with new Airport Extreme on 802.11n at 5ghz on MacRumors reports this issue with even earlier OSX.

Both DWA-171 rev A1 and DWA-131 rev E1 are working properly but you need to download drivers from Edimax for OSX 10.10. EW-7822UAC, EW-7811UTC, EW-7811UAC, EW-7811DAC, EW-7811USC are using the same Realtel RTL8811AU chip.

Test Method

It is detail explained in Prepare Your NAS File Transfer Performance Test with Mac OSX Client. I test both Samba and NFS.

I also add test results from Thecus W5000 with OSX client as reference.

Thecus W5000 with Mac OSX File Transfer Performance Report

Performance

Analyze

Mac mini‘s build-in 802.11n at 5GHz is faster than DWA-171‘s 802.11ac even has a slower connection speed. Both are slower than Fast Ethernet. It seems there are compatibility issue between DWA-171 and RT-AC51U or 802.11ac should be faster than 802.11n at 150Mbps.

If both using DWA-171‘s 802.11ac, though with higher theoretical bandwidth, it is actually slower than using DWA-171 on Mac mini and Fast Ethernet on W5000.

If Mac mini use its build-in 802.11n at 5GHz, Fast Ethernet on W5000 is faster than DWA-171‘s 802.11ac.

If Mac mini use DWA-171‘s 802.11ac, for W5000, Fast Ethernet is the fastest. Then comes DWA-171‘s 802.11ac at the same 5GHz. DWA-131 at 2.4GHz is so slow that I give up finishing the test.

TS-119PII with DWA-171‘s 802.11n at 2.4GHz is slower than Mac mini with build-in 802.11n at 5GHz or 802.11ac to W5000 with Fast Ethernet.

I already know there are compatibility issue between Windows Server 2012 R2 and OS X from Improving OS X SMB server share performance to Windows Server 2008R2 on JAMF Nation but it doesn’t seems the primary reason in this test.

Considering TS-119PII performs well with OS X, wireless real-world through-put and compatibility might be the issue. 16 款 802.11ac 路由器與網卡採購：要快還要穩，決戰2.4、5GHz 雙頻段 on 電腦王 also share the poor stability, performance, and compatibility experience for those using Realtek chips. Check on WikiDevi before you buy!

More Thoughts

I have learned it is more complex to test wireless transfer. The connection speed is not a constant and will change because of conflict, distance, and noise. Besides, compatibility among chips still needs to be improved.

Upsangel shares his real-world wireless throughput experience in 802.11AC路由Router選購技術攻略：不花冤枉錢的ac網絡架設指南 and 一分鐘了解什麽是802.11ac WIFI – 本年度買Router路由器必須瞭解的AC無線製式 as below:

802.11n	1T1R	2T2R	3T3R
Theoretical	150Mbps	300Mbps	450Mbps
Upsangel		~80Mpbs	~200Mpbs
802.11ac
Theoretical	433Mbps	867Mbps	1.3Gbps
Upsangel	~100Mpbs	~250 to 300Mpbs	~350Mpbs

Something is interesting. OS X is holding back the 2013 MacBook Air’s 802.11ac Wi-Fi speeds on ArsTechnica says the TCP window size stay within 64KB and limits file transfer speeds to about 21.2MBps when using wireless device. I think it’s worth the time to read for detail.

Thecus W5000 and QNAP TS-119PII with Mac OSX Wireless File Transfer Performance Report

Asus RT-AC51U

D-Link DWA-171 Rev A1

D-Link DWA-131 Rev E1

Thecus W5000 with Windows Storage Server 2012 R2 Essential

QNAP TS-119PII

Mac Mini Late 2012

Test Method

Performance

Analyze

More Thoughts

Reference

Published by Amigo

Leave a comment Cancel reply

Asus RT-AC51U

D-Link DWA-171 Rev A1

D-Link DWA-131 Rev E1

Thecus W5000 with Windows Storage Server 2012 R2 Essential

QNAP TS-119PII

Mac Mini Late 2012

Test Method

Performance

Analyze

More Thoughts

Reference

Share this:

Related

Published by Amigo

Leave a comment Cancel reply