[TUHS] OSI stack (Was: Posters)

Bakul Shah bakul at bitblocks.com
Tue Feb 5 07:13:17 AEST 2019

On Feb 4, 2019, at 12:29 PM, Noel Chiappa <jnc at mercury.lcs.mit.edu> wrote:
>> From: Grant Taylor
>> I'm not quite sure what you mean by naming a node vs network interface.
> Does one name (in the generic high-level sense of the term 'name'; e.g. an
> 'address' is a name for a unit of main memory) apply to the node (host) no
> matter how many interfaces it has, or where it is/moves in the network? If so,
> that name names the node. If not...

Xerox Network System (XNS) also had this property. A node had a
unique 48 bit address and each network had a unique 32 bit address.
Absolute host numbering meant you could move a host to another
network easily. IDP packet layout:

{checksum(2), length(2),
 transport ctl(1), packet type(1),
 dst net(4), dst host(6), dst socket(2),
 src net(4), src host(6), src socket(2),
 transport data(0 to 456), pad(0 to 1 byte)

IDP is @layer 3, same as IPv4 or IPv6.

More information about the TUHS mailing list