[Nml-wg] Tube Terminology

[Aaron Brown]

Jeroen van der Ham wrote:
> Figure 1 shows several terms:
> - *connection point* is any point that can make a connection (the 
> circles in the figures)
> - *network connection* is the terminated connection from A to B.
> - *link connection* is a direct connection between two connection points.
> - *subnetwork connection* is a connection between two connection 
> points that you can not or do not want to  describe the details of.
> - *tandem connection* is a concatenation of link connections
>
> Figure 2 shows a multi-layer network connection between X and Y. If we 
> start from X, we first encounter an *adaptation* to a lower layer. 
> Then we go through another link connection. At that connection point 
> we use *multiplexing* to adapt to a lower layer to connection point A. 
> Then we use the same network connection as in figure 1 to go to B, 
> where we go through *multiplexing*, a *link connection*, and an 
> *adaptation* to arrive at Y.
> Note that the multiplexed connection can also be viewed as a link 
> connection on a higher layer. The same goes for the connection between 
> X and Y, which is a link connection at the highest layer. And because 
> the connection is therminated there, it is also a network connection.

Both a network and a link connection seem to be 'connections between two 
points'. You say that in one case it's terminated and in one case it's 
not. Is 'terminated' a property of the link or is it a property of the 
connection point (or the node the connection point is attached to, 
depending on one's definition of connection point)? What differentiates 
a link whose contents gets demux'd to an higher layer vs. a link whose 
contents get routed at the same layer?

A subnetwork connection is a link or network connection that you view as 
opaque, correct? I.e. I've got a connection between these two points, i 
either don't know or don't care how it's constructed. If so, would 
"opaque connection" be a more clear description?

A tandem connection is a network or link connection that spans multiple 
connections? How does it differ from a network connection which in 
figure 1 also spans multiple connections?

Cheers,
Aaron