sell shell accounts?

Wed Jul 24 01:10:46 UTC 1996

It's ATM day.

| Consider the following configuration

|    ________           _______________________          ________
|   | Router | loop A  |                       | loop C | Router |
|   |   A    |=========| Wide-Area ATM Service |========|   C    |
|   |________|         |_______________________|        |________|
|                                  |
|                                  | local loop B
|                                  |
|                              ________
|                             | Router |
|                             |   B    |
|                             |________|

Consider the following configuration:

	Ra----fibrepath2----------RbRc------fibrepath2--------Rd

or the following:

	Ra---ll1---[IXCi]---ll2---RbRc---ll3---[IXCii]---ll4--Rd

I wonder what the distribution is, in terms of number of
backbones, of each of the three models.

(You may choose to imagine easy extensions like Ra and Rd
really being two routers, with physical connectivity between Ra' and Rd')

In terms of designing Internet backbones, do you see any
issues other than cost when choosing between your version
and either one of my versions?

Also, does this change when there are, say, twenty-odd
routers at each of the three locations?

	Sean.