I have several questions related to the behavior & throughput of a WAP, hope you can guide me in the right direction or give me some insights.
I have a WAP (Unifi nanoHD), which is mainly aimed for distributing HD-videos wireless to multiple users from a local Server. (Server-->10G line --> Switch --> 1G POE line --> nanoHD -->wireless--> client).
Observation: If I have too many clients (above around 6), I see that some of the Videos are buffering and/or the playback is stuttering. But on the same time, if I check the input data rate to the nanoHD it's only around 120 Mbps. So I was wondering what the cause could be, since in my understanding the bandwidth should still have some margin?!
So I investigated into understanding SU/MU-MIMO but would like to know more about it :
The datasheet of the WAP mentions that the nanoHD (4x4) can serve four 1x1 clients with MU-MIMO
- what happens if I have 4 clients, but they are 1x1, 1x1, 2x2, 2x2: are they all running on 1x1 or does the WAP packages them differently?
- what happens if I have a client not capable of MU-MIMO, how is this client served? Are the other clients affected by this? --> this point was answered by this: How do MU-MIMO routers handle non-MU-MIMO devices?
The datasheet states, that on 2.4Ghz I have 2x2 MIMO and on 5Ghz i have 4x4 MIMO, does that mean i could serve 5 clients at the same time? (1x on the 2.4GHz on SU-MIMO and four(4x) with 1x1 MU-MIMO (related to above question)?
What is the behavior of the signal distribution, if I have for example 8 clients, and all are MU-MIMO capable? Are the 4x spatial streams split between the 8 clients (meaning, that each antenna would serve 2 clients, and would "jump/go around" between each client to serve them data, or does it do a full loop?)
General: The radio rates are stated to 2.4 Ghz: 300 Mbps and 5Ghz: 1733 Mbps throughput: How are these rates split/achieved if the data-input (via LAN) is max. 1 Gbps? Shouldn't the max. output be the same as the max. input (=1Gbps)?
Additionally, for the video streaming use-case, how can i determine if my WAP is capable of handling the amount of clients? Until now I was only looking at throughput (assuming 6x video-streams, and 50 Mbps per Stream, would mean 300 Mbps output from the WAP). But taking the client "jump" into consideration, I was wondering how to determine the "loop-time (Time Slice 1-5)" for buffering:
Spatial Streams
Time Slice | 1 | 2 | 3 | 4 |
1 | A | A | - | - |
2 | B | - | - | - |
3 | C | C | D | D |
4 | E | E | F | F |
5 | A | A | - | - |
Thanks in advance for your help!
