Lucy, I agree with what you say here. This is a fact to consider especially if the PCE architecture is to be adapted later on for inter-AS TE in the ‘Internet’. What you say here is important if we consider the Internet peering models.
Regards, Meral Shirazipour Selon Lucy Yong <[EMAIL PROTECTED]>: > Adrian, > > > > The draft layouts the basic PCE architecture and expresses the motivation > for a PCE-based architecture. It is a good document. > > Beyond these motivation facts, I think we should have another incentive for > a PCE-based architecture. > > > > Today, a control plane based switching architecture assumes a user-network > model or client-server model. A LSP is initiated at an end user point > (client), then network establishes the LSP thru. the control plane > instantly. PCE reserves that concept too. Thus all connection paths are > based on instant requests from end users. > > > > In carrier reality world, it is hard to see that transport service will be > offered this way only, especially for a large bandwidth and permanent > bandwidth request. Typically, carrier has a service order reservation > system, it allows customer to book a bandwidth ahead (pending order), > carrier will do traffic engineering based on the pending order and will > excuse the order when the time arrives. A path computer engine has a > capability of taking a consideration about future pending orders while it > computes a path. The architecture is pretty close to the PCE-based > architecture except a lot of manual operation. I think PCE should consider > this as its application too and revise the basic architecture to include > this functionality. > > > > Here is the recommendation for the PCE-based architecture: > > > > --------------- > | --------- | Routing ---------- > | | | | Protocol | | > | | TED |<-+----------+-> | > | | | | | | > | --------- | | | > | | | | | > | | Input | | | > | v | | | > ---------- Response | --------- | | | > | |Request | | | | | Adjacent | > | SORD |<--------> | | PCE | | | Node | > | |Input | | | | | | > ---------- | --------- | | | > ^ | ^ | | | > | | |Request | | | > | | |Response| | | > Service Order | v | | | > | --------- | | | > Service | | | | Signaling| | > Request | |Signaling| | Protocol | | > ------+->| Engine |<-+----------+-> | > | | | | | | > | --------- | ---------- > --------------- > > > Here, SORD is the service order reservation database, it contains all > service order requests in terms of ingress and egress points, bandwidth, > service type, time period for the request, etc. When PCE computes a path, it > could get input from SORD to indicate if there are some network resource is > already blocked out. When a booking order in SORD is ready to kick off, SORD > will send request to PCE for the path computation, then PCE will send a > service request to signaling engine to establish the LSP. > > > > It is clarified that not all pending orders in SORD need to reserve the > bandwidth ahead, carrier could have some policies in SORD to manage which > order need to reserve the bandwidth ahead and which is not. > > > > Be glad to hear your and other people comment on this suggestion. > > > > Regards, > > Lucy Yong > > Huawei Technologies, U.S. > > > > > > _______________________________________________ Pce mailing list [email protected] https://www1.ietf.org/mailman/listinfo/pce
