1. IEEE-1588 TM Profiles

2. [Page 1] Synchronization Categories Frequency synchronization (or syntonization) –Clocks are aligned in frequency Phase synchronization –Clocks are aligned in phase Time synchronization (or Time of Day) –Clocks are aligned to a common time base (TAI for instance)

3. [Page 2] Application Case Study 1 – GSM/UMTS FDD Base Station Frequency synchronization –Radio Interface requirement: Frequency accuracy +/- 50 ppb No on-path support Core Packet Network Ethernet Base Station Ethernet Base Station 1588 Slave Clock 1588 Grand Master Clock 1588 Slave Clock

4. [Page 3] Application Case Study 2 – UMTS TDD Base Station Frequency and phase synchronization –Radio Interface requirement: Frequency accuracy +/- 50 ppb –Phase alignment: 2.5 s May need on-path support Core Packet Network Ethernet Base Station Ethernet Base Station 1588 Slave Clock 1588 Grand Master Clock 1588 Slave Clock

5. [Page 4] Application Case Study 2 – 3GPP2 CDMA2000 Base Station Frequency and time synchronization –Radio Interface requirement: Frequency accuracy +/- 50 ppb –Same System Time –The pilot time alignment error: 3 s/10 s May need on-path support Core Packet Network Ethernet Base Station Ethernet Base Station 1588 Slave Clock 1588 Grand Master Clock 1588 Slave Clock

6. [Page 5] Profiles Different applications need different profiles –Need to understand the application According to IEEE-1588 TM a profile should define –Best master clock algorithm options –Configuration management options –Path delay measurement option (delay request-response or peer delay) –Range and default values of all configurable attributes and data set members –Transport mechanisms required, permitted, or prohibited –Node types required, permitted, or prohibited –Options required, permitted, or prohibited –It also allows to extend the standard

7. [Page 6] Profiles contd But… in addition to IEEE-1588 profile parameters, other aspects need to be considered Clock requirements –What is the clock bandwidth? What is the frequency and holdover accuracy? Etc… –ITU-T is working on the clock requirements Functions to be implemented (e.g., on-path support) –Does it support Boundary Clocks? –Does it support Transparent Clocks? –Does it support Synchronous Ethernet? Network Metrics –Does the network support QoS? –Characterization of the network – ITU-T is studying metrics to characterize the network (e.g., minTDEV) –Traffic load –Number of hops

8. [Page 7] On-Path Support Boundary Clocks –How many Boundary Clocks can we cascade on a synchronization trail? –What is the clock bandwidth? Transparent Clocks –Can it be used in a Unicast environment? Synchronous Ethernet –Well understood as it is similar to SONET/SDH –ITU-T finished all Recommendations for Synchronous Ethernet

9. [Page 8] Other work Protocols –IEEE-1588 TM defines mappings to UDP/IPv4 and UDP/IPv6 –What about MPLS? MIBs –Do we need different MIBs for different profiles? Security

10. [Page 9] Summary Good understanding of the application is needed for the IEEE-1588 profiles –Application requirements –Clock requirements needed to be taken into consideration –Network architecture It is extremely important to coordinate the work between IETF and ITU-T, Study Group 15, question 13 (Q13) –Synchronization experts participates in Q13 –Protocol experts participates in IETF

11. [Page 10] Thank You