Re: More Questions of Exchange Points

[bmanning () karoshi com]

> >     are not but that is a nit argument.  There are lots of ways to
> >     slice the exchange point.
>
> I did observe 2 exchange points have direct connection between them, does it mean
> they belong to the same switch fabiric?

        What does this mean? 

> >     If -ANY- isp provides transit off the exchange fabric,
> >     does that make it a transit exchange?  If not, why not?
>
> Are those private peering points?

        confusion of terms.   When bits cross an administrative boundary
        that can be called a "peering point".  Often times that administrative
        boundary has a policy associated with it. Policies may be implementated
        via BGP, ACLS, etc.  The pathological case is the T1 between
        Sprint and my home network.  The two endpoints of that circuit 
        comprise a peering point. Sprint controls one end, I control the
        other and we have agreed to fate share a common communications 
        path to swap bits.

        Multiple parties can agree to share a layer 2 media for exchanging
        bits.  For Internet, I make the distinction that the layer 1 media
        (glass, copper, freq.) must implement a shared broadcast domain, e.g.
        I can ARP between the MAC addresses of the connecting devices.
        Again, for Internet, the presumption is IP.  It is conceivable
        that an operator might get a big'ol switch (layer one) and configure
        it so that ports 1-10 are one broadcast domain, 11 & 12 are a second
        broadcast domain, and 13-20 are a third, leaving 21-24 for the fourt
        broadcast domain.  Or... four VLANS.   One switch, four networks.
        Assign an IP subnet for each.  That would be four exchanges.
        Now Zocalo & JAM, running on the first VLAN/exchange are assigned
        192.168.10.4 and 192.168.10.5 & can ping/peer with everyone else
        on VLAN 1-10.  HOWEVER, Zocalo & JAM want to do some nifty/cool 
        things that they really don't want anyone else to sniff out.
        So they create a VPN (extra credit for defining at least four
        ways to do this... over the SAME VLAN) and use 10.168.10.4 and
        10.168.10.5 for their private VPN.

        So.  Is this one exchange point (one switch), four exchange points
        ( 4 VLANS), or five exchange points ( 5 subnets)?  Which ones are
        public? Which ones are private?  and why?

> Regards,
>
> Ruomei