Asterisk QoS (MOS Score)

Question

I am trying to work with asterisk QoS (Call Quality), I have read many articles but none of them are clear to me, I hope I will get some good answer from here.

we are getting this data-values from asterisk channel when calls hang up.

ssrc=2000676536;
themssrc=1925648282;
lp=0;rxjitter=0.000000;
rxcount=1398;
txjitter=0.000181;
txcount=1514;
rlp=0;
rtt=0.000534

And here is the description of all values that we are getting from channel

Receiver End : ssrc means our ( Receiver) ssrc rxcount means the number of packets received. lp means lost packets/Lost packets rxjitter means our calculated jitter(rx)/Jitter

Sender End: themssrc means their ssrc txcount means transmitted packets/Sent packet rlp means remote lost packets/Lost packets txjitter means reported jitter of the other end/Jitter

Round Trip Time : rtt – round trip time/RTT

And here is the Calculation of getting MOS Score according to a value that I am getting from channel

Take the average latency, add jitter, but double the impact to latency then add 10 for protocol latencies

EffectiveLatency = ( AverageLatency + Jitter * 2 + 10 )

Implement a basic curve - deduct 4 for the R value at 160ms of latency (round trip). Anything over that gets a much more agressive deduction

if EffectiveLatency < 160 then
  R = 93.2 - (EffectiveLatency / 40)
else
  R = 93.2 - (EffectiveLatency - 120) / 10

Now, let's deduct 2.5 R values per percentage of packet loss

R = R - (PacketLoss * 2.5)

Convert the R into an MOS value.(this is a known formula)

MOS = 1 + (0.035) * R + (.000007) * R * (R-60) * (100-R)

Now check on the 1st line of calculation

EffectiveLatency = ( AverageLatency + Jitter * 2 + 10 ) 

1. what is the AverageLatency & from where to get it

2. what is the Jitter, I mean which Jitter is it, because we are getting 2 Jitters value 1. Local_Server Jitter & 2. is Remote_Server Jitter so Here which Jitter is it.

Now check another line of calculation which is

R = R - (PacketLoss * 2.5)

Here we have also the same problem, what is the PacketLoss, I mean which PacketLoss is it because we are getting 2 PacketLoss value, 1. Local_Server PacketLoss & 2. is Remote_Server PacketLoss so here which PacketLoss is it?