need help quick Q on commun-protocol

[snypercore]

this is for an essay of mine i have to explain the main functions of a communications protocol and also i have to include the general layout (packet structure) of each protocol...

Communications Protocols

my Q is in the URL above the 1st diagram which they call a data unit is that a packet?

 

[Law]

Yes, that's the layer 3 PDU

 

[snypercore]

thanks havnt had time to reply but i read the post and finished it cheers