I think it would be easy enough to implement something in the scheduler
that says 8X MIMO-B downlink = good dog, you get the most air time, and
then scale it down from there. And make it dynamic enough so that if
there ends up being free time, then don't punish the low mod SMs all
that much, i.e. try to deliver their CIR or MIR if it can. OK, so
probably not so easy to implement.
On 11/14/2015 11:32 AM, Bill Prince wrote:
What would be ideal would be to base the scheduling on air time, and
increment a counter if air time is insufficient to provide the CIR
(and/or the MIR for that matter).
If we could monitor the CIR/MIR starvation, then we would be able to
get a handle on which subscribers are hitting the starvation and
(hopefully) be able to do something about it.
bp
<part15sbs{at}gmail{dot}com>
On 11/13/2015 8:04 AM, Aaron Schneider wrote:
The Canopy scheduler operates with a combined priority based scheme
and a round robin based scheme. As has been covered here in the past,
the scheduling priority is as follows: 1) High Priority CIR 2) Low
Priority CIR 3) Bcast/Mcast CIR 4) High Priority 5) Low Priority
6) Bcast/Mcast.
If you don't oversubscribe your CIR, then things are fine. But, that
is very tricky when you assume CIR based on one data rate (say 8x),
and the actual link requiring that CIR is different (say 4x). Now,
that SM is requiring twice as much frame time to meet that CIR as you
may have planned. This goes to the concept of allocating capacity
based on throughput, and it is generally how Canopy works. The round
robin comes in so that one SM can't take everything on its own, it
will try to be fairer, but, it will still do everything it can to
honor the CIRs of each SM in every frame.
We do have a feature in the works where we flip that a bit where the
CIR becomes airtime based so generally speaking, you are guaranteeing
air time and not throughput. The idea is that you will assign a CIR
based on a given rate, say 8x, and if the SM drops (or can only ever
achieve) 4x, then they will get half the data rate because they are
only allowed the same amount of time as if they were 8x. The
underlying concept is easy, it is the external interface and making
it easily understood and helping you stay out of trouble with
configurations that is difficult. If it is OK to just say turn on
the option, but then not be able to predict the throughput, that's
one thing, but if you have a customer that needs a given throughput
no matter what his data rate becomes, and other customers that are OK
with just having limited airtime access, then the overall planning of
CIR becomes tricky to not over-commit.
So what would you all prefer? An option per sector to enforce CIR in
a given way for all SMs? Or enforce CIR in a selectable way
(throughput vs. air time) per individual SMs on a given sector?
Regards,
-Aaron
-----Original Message-----
From: Af [mailto:[email protected]] On Behalf Of Adam Moffett
Sent: Friday, November 13, 2015 8:28 AM
To: [email protected]
Subject: Re: [AFMUG] LTE Speeds
Maybe it already does? They say capacity is allocated proportional
to sustained rate when there's contention....do they mean "capacity"
in bps or "capacity" in time slots. I'm thinking it's the latter
because I have observed that if you improve the data rate of an
individual SM he'll get more, which makes sense if the SM's capacity
allotment is measured in timeslots rather than bits.
Where's Aaron Schneider when you need him?
On 11/13/2015 9:14 AM, Craig Schmaderer wrote:
Cambium if it is at all possible please please add this to the 450!!!!!
On Nov 12, 2015, at 4:51 PM, Dan Petermann <[email protected]> wrote:
LTE can be set for equal time or equal rate. Equal rate will drag
down the thruput of all users.
Equal time will only impact the user with a poor signal. If
everyones signal is great and one users radio signal is bad, that
user only gets the thruput that can be crammed into his timeslot
because his modulation is low. Everyone else continues as normal.
At least that is my understanding.
On Nov 12, 2015, at 3:01 PM, Adam Moffett <[email protected]>
wrote:
....any system with 20mhz channels + two chains + 256QAM can claim
100mbps.
Getting past that is going to be carrier aggregation (bigger
channels) and MU-MIMO.
5x20mhz channels aggregated = 500mbps.
MU-MIMO can theoretically double capacity. So there's your 1gig.
I'm not clear on how far you can count on MU-MIMO. In theory it
sounds promising.
....and yes, one person at MIMO-A QPSK is going eat up many times
the capacity of a person at 256QAM MIMO-B no matter what wireless
system you're using. The best defense against that will be don't
install bad connections. Nothing new there.
If you're going to use 100mhz, you could of course install 5 AP's
of your choice and claim you have a 500mbps system.
On 11/12/2015 4:47 PM, Matt wrote:
Hear talk of these 50 - 100+ mbps speeds per user and eventually 1
gbps. How can LTE do that in 10 to 20 mhz of spectrum? I assume
if you are offering 50 mbps package in a sector its safe to assume
at prime time there are going to be at the very least 10 people
using it in that sector at the same time? Also assume some have
less then perfect connections to the tower using more air time.
