var segments = sr.WorkingSegments.Cast<ServiceSegment>().Concat(sr.ProtectionSegments.Cast<ServiceSegment>());
var connections = from s in segments
                  from p in s.SegmentParcels.Cast<SegmentParcel>
                  let nc = p.NetworkConnection
                  where nc != null
                  select nc;
foreach(var connection in connections)
    Collect(connection, protection);