|
Integrated Services Example: Data Path
|
| bet | 4/12 | | Sana | 26.12.2023 | | Hajmi | 492 Kb. | | #128375 |
Bog'liq qos-f05Integrated Services Example: Data Path Integrated Services Example: Data Path - Per-flow buffer management
Integrated Services Example How Things Fit Together Service Classes - Multiple service classes
- Service: contract between network and communication client
- End-to-end service
- Other service scopes possible
- Three common services
- Best-effort (“elastic” applications)
- Hard real-time (“real-time” applications)
- Soft real-time (“tolerant” applications)
Worse-case : Guaranteed Services - Service contract
- Network to client: guarantee a deterministic upper bound on delay for each packet in a session
- Client to network: the session does not send more than it specifies
- Algorithm support
- Admission control based on worst-case analysis
- Per flow classification/scheduling at routers
Average-case: Controlled Load Service - Service contract:
- Network to client: Average delay, jitter, bandwidth, e.g., makes network appear as an unloaded, best effort network with bandwidth and delay
- Client to network: the session does not send more than it specifies
- Algorithm Support
- Admission control based on measurement of aggregates
- Scheduling for aggregate possible
Role of RSVP in the Architecture - Signaling protocol for establishing per flow state
- Carry resource requests from hosts to routers
- Collect needed information from routers to hosts
- At each hop
- Consult admission control and policy module
- Set up admission state or informs the requester of failure
RSVP Design Features - IP Multicast centric design
- Receiver initiated reservation
- Different reservation styles
- Soft state inside network
- Decouple routing from reservation
RSVP Reservation Model - Performs signaling to set up reservation state for a session
- A session is a simplex data flow sent to a unicast or a multicast address, characterized by
- Multiple senders and receivers can be in session
|
| |
