1. When shaping using MQC on a interface that also passes VoIP traffic (priority queuing of voice traffic via child policy) what are the pros and cons of using a Tc of 4ms (minimum possible as far as I understand) compared with a Tc of 10ms (Cisco recommended value for voice in some documents I have seen). For example the impact on CPU or possible delay.

2. If shaping is configured as follows how are packets larger than Bc accommodated? (no interleaving configured).

CIR = 1000000bps
Bc = 4000bits (500bytes)
Be = 0
Tc = 4ms

3. Again with the above shaping configuration, if only packets of size 400bytes were sent does that mean it will never be possible to utilise the full 1000000bps but rather only 400/500 * 1000000 = 800000bps?

4. Using IOS 12.4.13b it was possible to see the stats for delayed packets and other values such as Tc.

router#show policy-map interface gi0/0
GigabitEthernet0/0

 Service-policy output: SHAPE

   Class-map: class-default (match-any)
     7522946 packets, 1961480754 bytes
     30 second offered rate 66000 bps, drop rate 0 bps
     Match: any
     Traffic Shaping
          Target/Average   Byte   Sustain   Excess    Interval  Increment
Rate Limit bits/int bits/int (ms) (bytes) 5000000/5000000 6250 50000 0 10 6250
       Adapt  Queue     Packets   Bytes     Packets   Bytes     Shaping
       Active Depth                         Delayed   Delayed   Active
       -      0         7518711   1956530048 118002    129484844 no

I can't seem to get the same stats from 12.4.22T

router#show policy-map interface fa0/0 output
FastEthernet0/0

 Service-policy output: SHAPE

   Class-map: class-default (match-any)
     13 packets, 2184 bytes
     30 second offered rate 0 bps, drop rate 0 bps
     Match: any
     Queueing
     queue limit 64 packets
     (queue depth/total drops/no-buffer drops) 0/0/0
     (pkts output/bytes output) 13/2366
     shape (average) cir 3000000, bc 12000, be 12000
     target shape rate 3000000

Any ideas?

Thanks

Ivan
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