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Shaping and Policing values - Layer 2 Headers

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This is 2 part question.

1. Are there any types of shaping/policing/LLQ etc that dont include Layer 2 in the bandwidth calculation?

My summary:

LLQ = Includes Layer 2 header size

MQC Policer = Includes Layer 2 header size

MQC Shaper = Includes Layer 2 header size

Legacy Frame-relay shaper = Includes layer 2 header size

 

2. Which header sizes are used?

This seems to be quoted differently on INE. In the Vol1 QoS workbook the value to use for Frame-relay BW calculations is 7 Bytes additional for each IP packet. Mark Snow and Petr Lapukov both use different numbers to each other in the following links. Having said that, Petr seems to agree with Mark that 4 bytes is the correct value for Frame-relay (see green boxes in the blog article) but then uses 7 bytes in his calculation example. What should I use in the exam? Is it the full Layer 2 header or only the part that the IOS queue scheduler uses in its calculations? 

http://blog.ine.com/2008/10/17/computing-voip-traffic-bandwidth-consumption/

http://ieoc.com/forums/p/15886/133024.aspx#133024 

Full Header sizes:

HDLC = 7 Bytes

Frame-relay = 7 Bytes

PPPoFr = 9 bytes

Ethernet = 18 bytes

Dot1q = 22 bytes

 

IOS Queue scheduler calculates sizes as:

 

HDLC = 4 Bytes

Frame-relay = 4 Bytes

PPPoFr = 4 bytes

Ethernet = ? bytes

Dot1q = ? bytes

 


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