SLA

The ASON network can provide services of different QoS to different clients.

The service level agreement (SLA) is used to classify services according to the service protection, as listed in Table 1. The rerouting time is related to the device type, interrupted service, network resource and setting. The data are listed as follows only for reference.

**Table 1** Service level
Service	Protection and Restoration Scheme	Implementation Means	Switching Time	Rerouting Time
Diamond service	Protection and restoration	Intra-board 1+1 protection, ODUk SNCP, SW SNCP and rerouting	Less than 50 ms	The rerouting time varies with the network size, capacity and service types. For the typical scenario of a four-NE mesh network transmitting no more than 40 wavelengths, the rerouting time is counted in seconds.
Silver service	Restoration	Rerouting	-
Copper service	No protection No restoration	-	-	-

Table 2 lists details of the TE links used by ASON services.

**Table 2** TE links used by WDM ASON trails
Service Level	Working Resource of TE Link	Protection Resource of TE Link	Non-Protection Resource of TE Link
Diamond service	Not used	Not used	Used
Silver service	Not used	Not used	Used
Copper service	Not used	Not used	Used