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Nested and Overlapping Protection

M Vinod KumarDr. Abhay Karandikar

Nested and Overlapping ProtectionSingle TESI (Qay)

With Segment Protection With Global Protection (GP, Qay)

Nested SegmentsWith Segment Protection

Fixed Timer

Feedback

Fate-sharing

Fixed Timer

Feedback

Fate-sharing

Overlapping Segments

Certain TESI is outside the scope of ISP; Only GP for them

Nested or Overlapping Segments

1 2 3 4 5

6

Inner-work Outer-work

Outer-Protect_1inner-Protect

7

Outer-Protect_2

Inner-work fails => Outer-work failsInner-Protect fails => Outer-Protect_1 failsThere is consistent protection switching if fate is shared

Forcing Fate-share

Nested or Overlapping Segments

1 2 3 4 5

6

7

Inner-work_1 Outer-work

Outer-Protect_1inner-Protect_1

Outer-Protect_2

inner-Protect_2

Inner-work_2

Outer-Protect_3

There is forwarding ambiguity at Node 7

Is covered in another prez

Questions?

THANK YOU