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Re: MPE and ULE padding
See in-line.
Simon Teh wrote:
Dear all IP-DVB members,
Good morning, I have several questions about ULE and MPE padding. As we
know that the size of ULE and MPE are variable size (MTU 1500 bytes),
The Maximum MTU of MPE is defined as a little less than 4KB.
The Maximum MTU of ULE is defined as a little less than 32KB.
Although, as you say 1500 is a common MTU for *classical* Ethernet.
so
if the actual data is really small (maybe 2 bytes):
I don't know of any packet which is this small in the IP world, but sure we
can and do expect packets much less than the MTU.
My Questions:
1. Will it be padded until the PDU reach an expected length by MPE
and ULE?
It **CAN** be padded to fit exactly into an under-lying Transport Stream
Packet (183B payload). **OR** if Packing is supported - i.e. the MPE driver
supports (many do, and *ALL* ULE ones do), then you do not need normally to
add any padding.
The ULE spec explains this process.
2. Do the MPE and ULE have a minimum size? If yes what is the
minimum size for MPE and ULE?
No (unless you refer to the TS Packet size).
Thank you!
Best Regards,
Simon Teh
Universiti Sains Malaysia
Gory Fairhurst.