var google.golang.org/grpc/internal/envconfig.ALTSHandshakerKeepaliveParams

one use

	google.golang.org/grpc/internal/envconfig (current package)
		envconfig.go#L79: 	ALTSHandshakerKeepaliveParams = boolFromEnv("GRPC_EXPERIMENTAL_ALTS_HANDSHAKER_KEEPALIVE_PARAMS", false)