frame relay

mattau

when they say frame relay is considered packet switching how does this work with a permanent virtual connection.

doesnt pvc more or less act like a leased line ? and therefore the packets that you send should only go through one path to get to the destination vs going through several interconnected paths within the cloud ?

how can it for example go through DLCI x and get to the DLCI on the other side by each packet taking different paths. When you buy a path from a service provider dont they set it up so it acts like a leased line and just the 1 path to your other destination (obviously you dont see the traceroute to within the cloud you only see that you have a direct route from A to B straight through. )

hope someone can clear this up for me. Unless what i am thinking is correct then just clarify for me

mattau

I think i found my answer on the microsoft site

In a connection-oriented service, the communications link is made before any packets are transmitted. Because the link is established before transmission begins, the packets comprising a message all follow the same route to their destination. In establishing the link between sender and recipient, a connection-oriented service can make use of either switched virtual circuits (SVCs) or permanent virtual circuits (PVCs):

Using a switched virtual circuit is comparable to calling someone on the telephone. The caller connects to the called computer, they exchange information, and then they terminate the connection.

Using a permanent virtual circuit, on the other hand, is more like relying on a leased line. The line remains available for use at all times, even when no transmissions are passing through it.

so i think i am correct in saying it is like a leased line that always has one path although the path is unknown as the service provider constructs that path through their network