Should "Short GI" be disabled when using Mixed N/G

Post new topic   Reply to topic    DD-WRT Forum Forum Index -> Atheros WiSOC based Hardware
Author Message
tm23
DD-WRT Novice


Joined: 29 Jan 2016
Posts: 30

PostPosted: Fri May 06, 2016 16:46    Post subject: Should "Short GI" be disabled when using Mixed N/G Reply with quote
Hi all,

I was reading on weather to enable the Short GI feature in ddwrt, and found this article on a Dlink website:


Quote:
2. Short Guard interval & Aggregation
In the screen shot above you will notice that Short Guard Interval and Aggregation are both disabled. If you would use mixed mode, always make sure these are disabled, as these features were designed to be used with 802.11n, and can cause issues with mixed mode. If you are using 802.11n only, you may wish to enable these features as they will generally result in increased throughput


https://support.software.dell.com/kb/sw10984

In my ddwrt settings, Short GI was automatically enabled when I selected "N/G mixed" as the mode. Should I disable Short GI when using mixed N/G devices or does ddwrt manages this differently than a Dlink router firmware?

My router info is below:

Rosewill RNX-N300RT (rebranded WR841N_V7)
ddwrt 04-04-2016-r29396
Sponsor
alceryes
DD-WRT Novice


Joined: 09 Mar 2007
Posts: 35

PostPosted: Fri May 06, 2016 17:28    Post subject: Reply with quote
Short GI in N/G mode can cause issues but it's not a definite. Run some tests with your devices with the setting enabled and disabled and see how it goes.
tatsuya46
DD-WRT Guru


Joined: 03 Jan 2010
Posts: 4429
Location: Winnipeg, Canada

PostPosted: Fri May 06, 2016 17:46    Post subject: Reply with quote
leave it on
_________________
LATEST FIRMWARE(S) || Qualcomm Atheros Wi-Fi Settings || Qualcomm Atheros Repeating

[QUALCOMM ATHEROS] EA8500 --------------> DD-WRT v3.0-r29957 std (private test)
[QUALCOMM ATHEROS] DIR-862L A1 --------> DD-WRT v3.0-r30016 std
[QUALCOMM ATHEROS] DIR-862L A1 --------> DD-WRT v3.0-r30016 std
▲ ACTIVE / INACTIVE ▼
[QUALCOMM ATHEROS] WNDR4300 v1 ------> DD-WRT v3.0-r29968 std

BrainSlayer wrote:
we just do it since we do not like any restrictions enforced by stupid cocaine snorting managers



Never forget mm/cl/AM I LOVE YOU, forever..
mrjcd
DD-WRT Guru


Joined: 31 Jan 2015
Posts: 1033
Location: Texas

PostPosted: Fri May 06, 2016 19:01    Post subject: Reply with quote
Short GI and NG-Mixed has always worked fine for me in configrations mentioned ---
WNDR3700v4 - AP / CB (repeater) / WDS (on 5GHz also)
WRT160NL - AP / WDS / CB (repeater)
WRT2100L - AP / WDS / CB (repeater)
tm23
DD-WRT Novice


Joined: 29 Jan 2016
Posts: 30

PostPosted: Fri May 06, 2016 19:36    Post subject: Reply with quote
ok, I will leave it on. However, I did turn it off to see what would happen, and the most notable thing on the Sys info page was that the RX rate dropped to 130Mbps from 150Mbps (I have all N adapters, one is a G). I don't know if there are other effects. I ran speedtest.net, but that didn't show much of a difference in ping or throughoutput compared to when I had SG-I turned on.
tatsuya46
DD-WRT Guru


Joined: 03 Jan 2010
Posts: 4429
Location: Winnipeg, Canada

PostPosted: Sat May 07, 2016 6:28    Post subject: Reply with quote
search up "wifi sweetspots" for android/ios devices, it tests RX (receive) router sensitivity VERY, intensively & its a free (GOOD) app.
_________________
LATEST FIRMWARE(S) || Qualcomm Atheros Wi-Fi Settings || Qualcomm Atheros Repeating

[QUALCOMM ATHEROS] EA8500 --------------> DD-WRT v3.0-r29957 std (private test)
[QUALCOMM ATHEROS] DIR-862L A1 --------> DD-WRT v3.0-r30016 std
[QUALCOMM ATHEROS] DIR-862L A1 --------> DD-WRT v3.0-r30016 std
▲ ACTIVE / INACTIVE ▼
[QUALCOMM ATHEROS] WNDR4300 v1 ------> DD-WRT v3.0-r29968 std

BrainSlayer wrote:
we just do it since we do not like any restrictions enforced by stupid cocaine snorting managers



Never forget mm/cl/AM I LOVE YOU, forever..
tm23
DD-WRT Novice


Joined: 29 Jan 2016
Posts: 30

PostPosted: Sat May 07, 2016 12:09    Post subject: Reply with quote
thanks, I will look for that. Smile
Display posts from previous:    Page 1 of 1
Post new topic   Reply to topic    DD-WRT Forum Forum Index -> Atheros WiSOC based Hardware All times are GMT

Navigation

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum