Ssh invalid identification string protocol

ssh - did not receive identification string
invalid ssh identification string telnet
invalid ssh identification string.
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ssh error did not receive identification string frominvalid ssh identification string netcat
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identification string from (SCANNER_IP) Mar 3 10:15:18 target sshd[1471]: Protocol major versions differ for (SCANNER_IP): SSH-2.0-OpenSSH_6.6.1 vs.io.IOException: Malformed server identification string. There was no line starting with 'SSH-' amongst the first 50 lines. at com.trilead.ssh2.transport.