$6\mathrm{.}7-1.$ To which protocol do these fields belong? We learned way back in Chapter $1$ that $"$a

protocol defines the format and the order of messages exchanged between two or more

communicating entities $..."$ and throughout the course, we saw many, many different

messages being used throughout the protocol stack, each with different fields.

In this question, for a given field name in a protocol message $($i$.$e$.,$ in an application$-$layer

message, transport$-$layer segment, network$-$layer datagram, or link$-$layer frame$),$ use the

pulldown menu to match the field name with the protocol $($or pair of protocols$)$ where this

field name is used. Each protocol name $($or pair of protocol names$)$ in the pull$-$down menu

should be matched to exactly one field description.

$$ IF$-$Modified$-$Since $->$

$128-$bit Source IP address field $->$

$$ Time$-$to$-$Live $($aka hop count$)->$

$$ Question field $($containing name being queried$)->$

$$ Source MAC address $->$

$$ MAC address $3->$

$$ From: $->$

$$ SYN bit $->$

$$ AS$-$PATH $->$

$$ Source port number $->$