[ih] Speaking of layering and gateways

[touch at strayalpha.com]

> On Apr 15, 2024, at 8:04 PM, John Levine via Internet-history <internet-history at elists.isoc.org> wrote:
> 
> It appears that Jack Haverty via Internet-history <jack at 3kitty.org> said:
>> Today we have container terminals, where cranes lift containers between 
>> rail cars and trucks.  We might call both of these "gateways"...
> 
> Containers are a standard size and shape and can be transported in
> many ways including ships, trains, and trucks, and moved from one to
> the other without looking inside. Seems a like like packets, no?

More like SONET [fixed size] frames, if you’re referring to ISO intermodal containers.
Although there are fractional sizes (half length, etc.), there’s one fixed dominant size.

> It is not my impression that there are a lot of loads suitable for
> containers but big enough to be be subject to fragmentation and
> reassembly.

Unpacking and repacking happens with pallets or sub-containers inside.

Like SONET frames, the idea is to avoid that step where possible.

Fragmentation and reassembly happens with payloads that don’t fit in a single container, but not with containers themselves.

That’s another reason why the analogy is a lot more like SONET frames than packets, IMO.

Joe